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BoP Lab / Classes / T2

T2 vs T1 vs SM vs FB pace at every track

Lap times across years say as much about the weather as the class. % of T2 is each class's best lap as a share of T2's on the same day, so the conditions drop out: 100% is level, less is quicker, and a move in it is the class getting faster or slower against the field.

Class · click a class to switch, + to compare alongside (up to 4: remove one to add another)
Series
Reference · what % is measured against
Tracks · untick to narrow

Closest to the field: T2 100.0% of T2 Kurt Rezzetano, Daytona International Speedway Runoffs 2015 race · T1 93.7% of T2 Andrew Aquilante, Indianapolis Motor Speedway Runoffs 2017 qualifying · SM 108.7% of T2 Michael Carter, Mid-Ohio Sports Car Course Runoffs 2016 race · FB 84.4% of T2 J R Osborne, Sonoma Raceway Runoffs 2018 qualifying

1:201:402:002:202:4046 rule changes between Runoffs 2018 and Runoffs 201946 ▾45 rule changes between Runoffs 2019 and Runoffs 202045 ▾49 rule changes between Runoffs 2020 and Runoffs 202149 ▾32 rule changes between Runoffs 2021 and Runoffs 202232 ▾37 rule changes between Runoffs 2022 and Runoffs 202337 ▾48 rule changes between Runoffs 2023 and Runoffs 202448 ▾52 rule changes between Runoffs 2024 and Runoffs 202552 ▾40 rule changes between Runoffs 2025 and Runoffs 202640 ▾T2 race best at Runoffs 2015: 2:01.077 (Kurt Rezzetano)T2 race best at Runoffs 2016: 1:32.691 (John M Buttermore)T2 race best at Runoffs 2017: 1:48.769 (John M Buttermore)T2 race best at Runoffs 2018: 1:45.999 (John Kachadurian)T2 race best at Runoffs 2019: 1:58.551 (Cooper I MacNeil)T2 race best at Runoffs 2020: 2:26.803 (Kurt Rezzetano)T2 race best at Runoffs 2021: 1:48.474 (Kurt Rezzetano)T2 race best at Runoffs 2022: 2:04.756 (Kurt Rezzetano)T2 race best at Runoffs 2023: 2:01.201 (Kurt Rezzetano)T2 race best at Runoffs 2024: 2:23.261 (Kurt Rezzetano)T2 race best at Runoffs 2025: 2:23.483 (Kurt Rezzetano)T2 race best at Runoffs 2026: 2:23.141 (Scotty B White)T2 qualifying best at Runoffs 2015: 2:00.172 (Kurt Rezzetano)T2 qualifying best at Runoffs 2016: 1:31.563 (Preston Calvert)T2 qualifying best at Runoffs 2017: 1:48.618 (John M Buttermore)T2 qualifying best at Runoffs 2018: 1:45.032 (John Kachadurian)T2 qualifying best at Runoffs 2019: 1:57.537 (Cooper I MacNeil)T2 qualifying best at Runoffs 2020: 2:24.195 (Alan Kossof)T2 qualifying best at Runoffs 2021: 1:47.509 (Kurt Rezzetano)T2 qualifying best at Runoffs 2022: 2:00.276 (Kurt Rezzetano)T2 qualifying best at Runoffs 2023: 1:59.504 (Kurt Rezzetano)T2 qualifying best at Runoffs 2024: 2:22.117 (Kurt Rezzetano)T2 qualifying best at Runoffs 2025: 2:23.351 (Kurt Rezzetano)T2 qualifying best at Runoffs 2026: 2:23.977 (Scotty B White)T1 race best at Runoffs 2015: 1:55.494 (Andrew Aquilante)T1 race best at Runoffs 2016: 1:29.309 (Ross Murray)T1 race best at Runoffs 2017: 1:42.871 (Andrew Aquilante)T1 race best at Runoffs 2018: 1:41.125 (Kristofer Olson)T1 race best at Runoffs 2019: 2:14.413 (Andrew Aquilante)T1 race best at Runoffs 2020: 2:18.701 (Mark Boden)T1 race best at Runoffs 2021: 1:43.752 (Mark Boden)T1 race best at Runoffs 2022: 2:16.067 (Andrew Aquilante)T1 race best at Runoffs 2023: 1:55.488 (Andrew Aquilante)T1 race best at Runoffs 2024: 2:16.131 (Andrew Aquilante)T1 race best at Runoffs 2025: 2:21.612 (Drew Delmonico)T1 qualifying best at Runoffs 2015: 1:53.562 (Andrew Aquilante)T1 qualifying best at Runoffs 2016: 1:28.656 (Ross Murray)T1 qualifying best at Runoffs 2017: 1:41.793 (Andrew Aquilante)T1 qualifying best at Runoffs 2018: 1:39.970 (Kristofer Olson)T1 qualifying best at Runoffs 2019: 1:54.771 (Andrew Aquilante)T1 qualifying best at Runoffs 2020: 2:17.646 (Andrew Aquilante)T1 qualifying best at Runoffs 2021: 1:42.292 (Andrew Aquilante)T1 qualifying best at Runoffs 2022: 1:54.890 (Andrew Aquilante)T1 qualifying best at Runoffs 2023: 1:54.520 (Andrew Aquilante)T1 qualifying best at Runoffs 2024: 2:16.578 (Andrew Aquilante)T1 qualifying best at Runoffs 2025: 2:20.677 (James Candelaria)SM race best at Runoffs 2015: 2:24.067 (Todd Lamb)SM race best at Runoffs 2016: 1:40.764 (Michael Carter)SM race best at Runoffs 2017: 1:59.100 (Michael Gagliardo)SM race best at Runoffs 2018: 1:55.278 (Michael Carter)SM race best at Runoffs 2019: 2:16.459 (Elivan Goulart)SM race best at Runoffs 2020: 2:43.748 (Preston Pardus)SM race best at Runoffs 2021: 1:58.837 (Brian Henderson)SM race best at Runoffs 2022: 2:19.107 (Travis Wiley)SM race best at Runoffs 2023: 2:16.229 (Julian DaCosta)SM race best at Runoffs 2024: 2:41.486 (Brett Kowalski)SM race best at Runoffs 2025: 2:44.430 (Kyle Greenhill)SM race best at Runoffs 2026: 2:42.725 (Francisco Barroso)SM qualifying best at Runoffs 2015: 2:18.661 (Andrew Carbonell)SM qualifying best at Runoffs 2016: 1:40.514 (Justin Hille)SM qualifying best at Runoffs 2017: 1:58.306 (Chris Haldeman)SM qualifying best at Runoffs 2018: 1:54.355 (Ken Sutherland)SM qualifying best at Runoffs 2019: 2:14.552 (Todd Buras)SM qualifying best at Runoffs 2020: 2:42.209 (Kyle Greenhill)SM qualifying best at Runoffs 2021: 1:57.695 (Brian Henderson)SM qualifying best at Runoffs 2022: 2:14.664 (Danny Steyn)SM qualifying best at Runoffs 2023: 2:14.986 (Danny Steyn)SM qualifying best at Runoffs 2024: 2:41.106 (Ethan Goulart)SM qualifying best at Runoffs 2025: 2:43.111 (Bobby Gossett)SM qualifying best at Runoffs 2026: 2:42.173 (Brett Kowalski)FB race best at Runoffs 2015: 1:51.616 (J R Osborne)FB race best at Runoffs 2016: 1:21.015 (Jeremy Hill)FB race best at Runoffs 2017: 1:33.702 (Alex Mayer)FB race best at Runoffs 2018: 1:31.189 (J R Osborne)FB race best at Runoffs 2019: 1:57.688 (Pete Frost)FB qualifying best at Runoffs 2015: 1:50.711 (J R Osborne)FB qualifying best at Runoffs 2016: 1:19.886 (Alex Mayer)FB qualifying best at Runoffs 2017: 1:33.746 (Gary Hickman)FB qualifying best at Runoffs 2018: 1:28.612 (J R Osborne)FB qualifying best at Runoffs 2019: 1:54.469 (Pete Frost)Daytona International Speedway · Runoffs 2015R2015Mid-Ohio Sports Car Course · Runoffs 2016R2016Indianapolis Motor Speedway · Runoffs 2017R2017Sonoma Raceway · Runoffs 2018R2018Virginia International Raceway · Runoffs 2019R2019Road America · Runoffs 2020R2020Indianapolis Motor Speedway · Runoffs 2021R2021Virginia International Raceway · Runoffs 2022R2022Virginia International Raceway · Runoffs 2023R2023Road America · Runoffs 2024R2024Road America · Runoffs 2025R2025Road America · Runoffs 2026R2026
T2T1SMFBsolid race · dashed qualifying · slower is lower
90%100%110%46 rule changes between Runoffs 2018 and Runoffs 201946 ▾45 rule changes between Runoffs 2019 and Runoffs 202045 ▾49 rule changes between Runoffs 2020 and Runoffs 202149 ▾32 rule changes between Runoffs 2021 and Runoffs 202232 ▾37 rule changes between Runoffs 2022 and Runoffs 202337 ▾48 rule changes between Runoffs 2023 and Runoffs 202448 ▾52 rule changes between Runoffs 2024 and Runoffs 202552 ▾40 rule changes between Runoffs 2025 and Runoffs 202640 ▾T2 race best at Runoffs 2015: 100.0% of T2's (Kurt Rezzetano)T2 race best at Runoffs 2016: 100.0% of T2's (John M Buttermore)T2 race best at Runoffs 2017: 100.0% of T2's (John M Buttermore)T2 race best at Runoffs 2018: 100.0% of T2's (John Kachadurian)T2 race best at Runoffs 2019: 100.0% of T2's (Cooper I MacNeil)T2 race best at Runoffs 2020: 100.0% of T2's (Kurt Rezzetano)T2 race best at Runoffs 2021: 100.0% of T2's (Kurt Rezzetano)T2 race best at Runoffs 2022: 100.0% of T2's (Kurt Rezzetano)T2 race best at Runoffs 2023: 100.0% of T2's (Kurt Rezzetano)T2 race best at Runoffs 2024: 100.0% of T2's (Kurt Rezzetano)T2 race best at Runoffs 2025: 100.0% of T2's (Kurt Rezzetano)T2 race best at Runoffs 2026: 100.0% of T2's (Scotty B White)T2 qualifying best at Runoffs 2015: 100.0% of T2's (Kurt Rezzetano)T2 qualifying best at Runoffs 2016: 100.0% of T2's (Preston Calvert)T2 qualifying best at Runoffs 2017: 100.0% of T2's (John M Buttermore)T2 qualifying best at Runoffs 2018: 100.0% of T2's (John Kachadurian)T2 qualifying best at Runoffs 2019: 100.0% of T2's (Cooper I MacNeil)T2 qualifying best at Runoffs 2020: 100.0% of T2's (Alan Kossof)T2 qualifying best at Runoffs 2021: 100.0% of T2's (Kurt Rezzetano)T2 qualifying best at Runoffs 2022: 100.0% of T2's (Kurt Rezzetano)T2 qualifying best at Runoffs 2023: 100.0% of T2's (Kurt Rezzetano)T2 qualifying best at Runoffs 2024: 100.0% of T2's (Kurt Rezzetano)T2 qualifying best at Runoffs 2025: 100.0% of T2's (Kurt Rezzetano)T2 qualifying best at Runoffs 2026: 100.0% of T2's (Scotty B White)T1 race best at Runoffs 2015: 95.4% of T2's (Andrew Aquilante)T1 race best at Runoffs 2016: 96.4% of T2's (Ross Murray)T1 race best at Runoffs 2017: 94.6% of T2's (Andrew Aquilante)T1 race best at Runoffs 2018: 95.4% of T2's (Kristofer Olson)T1 race best at Runoffs 2019: 113.4% of T2's (Andrew Aquilante)T1 race best at Runoffs 2020: 94.5% of T2's (Mark Boden)T1 race best at Runoffs 2021: 95.6% of T2's (Mark Boden)T1 race best at Runoffs 2022: 109.1% of T2's (Andrew Aquilante)T1 race best at Runoffs 2023: 95.3% of T2's (Andrew Aquilante)T1 race best at Runoffs 2024: 95.0% of T2's (Andrew Aquilante)T1 race best at Runoffs 2025: 98.7% of T2's (Drew Delmonico)T1 qualifying best at Runoffs 2015: 94.5% of T2's (Andrew Aquilante)T1 qualifying best at Runoffs 2016: 96.8% of T2's (Ross Murray)T1 qualifying best at Runoffs 2017: 93.7% of T2's (Andrew Aquilante)T1 qualifying best at Runoffs 2018: 95.2% of T2's (Kristofer Olson)T1 qualifying best at Runoffs 2019: 97.6% of T2's (Andrew Aquilante)T1 qualifying best at Runoffs 2020: 95.5% of T2's (Andrew Aquilante)T1 qualifying best at Runoffs 2021: 95.1% of T2's (Andrew Aquilante)T1 qualifying best at Runoffs 2022: 95.5% of T2's (Andrew Aquilante)T1 qualifying best at Runoffs 2023: 95.8% of T2's (Andrew Aquilante)T1 qualifying best at Runoffs 2024: 96.1% of T2's (Andrew Aquilante)T1 qualifying best at Runoffs 2025: 98.1% of T2's (James Candelaria)Off the chart: SM race best at Runoffs 2015: 119.0% of T2's (Todd Lamb)SM race best at Runoffs 2016: 108.7% of T2's (Michael Carter)SM race best at Runoffs 2017: 109.5% of T2's (Michael Gagliardo)SM race best at Runoffs 2018: 108.8% of T2's (Michael Carter)SM race best at Runoffs 2019: 115.1% of T2's (Elivan Goulart)SM race best at Runoffs 2020: 111.5% of T2's (Preston Pardus)SM race best at Runoffs 2021: 109.6% of T2's (Brian Henderson)SM race best at Runoffs 2022: 111.5% of T2's (Travis Wiley)SM race best at Runoffs 2023: 112.4% of T2's (Julian DaCosta)SM race best at Runoffs 2024: 112.7% of T2's (Brett Kowalski)SM race best at Runoffs 2025: 114.6% of T2's (Kyle Greenhill)SM race best at Runoffs 2026: 113.7% of T2's (Francisco Barroso)SM qualifying best at Runoffs 2015: 115.4% of T2's (Andrew Carbonell)SM qualifying best at Runoffs 2016: 109.8% of T2's (Justin Hille)SM qualifying best at Runoffs 2017: 108.9% of T2's (Chris Haldeman)SM qualifying best at Runoffs 2018: 108.9% of T2's (Ken Sutherland)SM qualifying best at Runoffs 2019: 114.5% of T2's (Todd Buras)SM qualifying best at Runoffs 2020: 112.5% of T2's (Kyle Greenhill)SM qualifying best at Runoffs 2021: 109.5% of T2's (Brian Henderson)SM qualifying best at Runoffs 2022: 112.0% of T2's (Danny Steyn)SM qualifying best at Runoffs 2023: 113.0% of T2's (Danny Steyn)SM qualifying best at Runoffs 2024: 113.4% of T2's (Ethan Goulart)SM qualifying best at Runoffs 2025: 113.8% of T2's (Bobby Gossett)SM qualifying best at Runoffs 2026: 112.6% of T2's (Brett Kowalski)FB race best at Runoffs 2015: 92.2% of T2's (J R Osborne)FB race best at Runoffs 2016: 87.4% of T2's (Jeremy Hill)FB race best at Runoffs 2017: 86.1% of T2's (Alex Mayer)FB race best at Runoffs 2018: 86.0% of T2's (J R Osborne)FB race best at Runoffs 2019: 99.3% of T2's (Pete Frost)FB qualifying best at Runoffs 2015: 92.1% of T2's (J R Osborne)FB qualifying best at Runoffs 2016: 87.2% of T2's (Alex Mayer)FB qualifying best at Runoffs 2017: 86.3% of T2's (Gary Hickman)FB qualifying best at Runoffs 2018: 84.4% of T2's (J R Osborne)FB qualifying best at Runoffs 2019: 97.4% of T2's (Pete Frost)Daytona International Speedway · Runoffs 2015R2015Mid-Ohio Sports Car Course · Runoffs 2016R2016Indianapolis Motor Speedway · Runoffs 2017R2017Sonoma Raceway · Runoffs 2018R2018Virginia International Raceway · Runoffs 2019R2019Road America · Runoffs 2020R2020Indianapolis Motor Speedway · Runoffs 2021R2021Virginia International Raceway · Runoffs 2022R2022Virginia International Raceway · Runoffs 2023R2023Road America · Runoffs 2024R2024Road America · Runoffs 2025R2025Road America · Runoffs 2026R2026
T2T1SMFBsolid race · dashed qualifying · each class's best lap as a share of T2's at the same event (the reference class, changeable above); 100% is level, less is quicker, so up the chart is quicker
EventT2T1SMFB
Qual best Race best Trap Qual best Race best Trap vs T2 % of T2 Qual best Race best Trap vs T2 % of T2 Qual best Race best Trap vs T2 % of T2 
Road America Runoffs 20262026-09-282:23.977Scotty B White · fastest of 22 · top 5 within 2.5s+0.626s (+0.44%)2:23.141Scotty B White · fastest of 18 · top 5 within 2.7s-0.342s (-0.24%)147.2Ami Wilson-6.9 mph (-4.5%)2:42.173Brett Kowalski · fastest of 34 · top 5 within 0.3s-0.938s (-0.58%)2:42.725Francisco Barroso · fastest of 35 · top 5 within 0.2s-1.705s (-1.04%)119.6Wyatt Couch+0.3 mph (+0.3%)+19.584squal +18.196s113.7%qual 112.6%
40 rule changes (T2: 26, T1: 12, SM: 2)6 weight · 5 cars added · 5 engine · 3 aero · 3 induction · 2 removed · 2 suspension & brakes · 2 tyres & wheels · 9 wording · 3 other · T2-TCR all models gain 300 lbs minimum weight; splitter ride height 3.50 inches, chassis 4.0 inches. · SM/SMX Mazda rear toe link part number revised from 0000-04-5361426 to 0000-04-5361. · T1 classes now require U-rated or better DOT tires; re-grooving DOT tires banned; shaving and truing only allowed. · T2-TCR adds 2023 Hyundai Veloster N TCR and Elantra N TCR, both SEQ transmission, 90% power level, 3000 lbs minimum weight. · T1 trunk lid and wing mounting wording clarified; no performance change. · T2 2015–2023 Ecoboost Mustang restrictor removed, tyres to 315, weight cut 100 lbs to 3300. · T2 Chevrolet Corvette C6 Coupe/Grand Sport gains permission for OEM C6 ZR1 and Z06 carbon splitter and spoiler dimensions. · T2-TCR Mazda 3 tyres capped at 275 section width; splitter, valance, ride height rules removed; TCR regulations source simplified. · T1 LS1, LS6 removes OEM designation; 70mm restrictor requirement deleted. · T1 Spec Line Coyote Boss 302 production years corrected to 11–14, displacement 4957 cc unchanged. · SM/SMX part number 0000-10-6900 replaced with 0000-06-5016-KT in GCR 9.1.7.C.1.j.1.c. · T1 restrictor requirement removed entirely; no replacement specified. · T2 BMW 435i brakes increased to 370mm front and 345mm rear from 340mm and 330mm. · T2 Porsche Cayman S year ranges and displacement specs adjusted for 2026 Atlanta HST. · T2 TCR cars must conform to 2024 TCR Technical Regulations; wheel size capped at 10" x 18", tyres at 275 max width. · T1 GT4 Spec Line 4030- permits Wagner Tuning #200001124 intercooler as replacement for OEM heat exchanger. · T2 BMW M235iR removes alternative tune permission. · T1 Chevrolet Corvette C6 LS1/LS6 spec line reinstated: 3200 lbs minimum, 70mm restrictor. · BMW 435i 2014–2017 added to T2 at 2979 cc, 40mm restrictor, 3400 lbs minimum weight. BMW M235i restrictor clarified to 40mm TIR. · Nissan Z including Nismo added to T2 with 2997cc, 38mm restrictor, 19in wheels, 3600–3650 lbs, 355–381mm brakes. · T2-T4 adjustable toe links now allow performance alternative bushings and spherical bearings, previously only spherical bearings permitted. · T2-TCR adds Link & Co 03 TCR and MG6 TCR at 3000 lbs, 90% power, sequential, 275 max tyre width. · T1 Spec Line removes 70mm flat plate restrictor option. · T2, T3, T4 now allow under-dash electronics relocation for access after roll cage installation. · T2 Cadillac CT4-V Blackwing minimum weight drops 50 lbs to 3750. · T2 C6 Corvette LS2 restrictor increases from 67mm to 80mm FPR. · T2 Dodge Viper SRT10 coupe 03-06 minimum weight cut 25 lbs to 3650. · T2 Mustang GT 5.0L gains Ford Track/Performance Package rear spoiler aero parts. · T4 Performance clarified: 1-piece alternative rotors permitted only at sizes listed in spec line; alternate brake kits may use matching 1-piece rotors. · unclear · T1 non-GT4 cars: multiple restrictor increases 61–80mm range, one weight raise to 3600 lbs, L76 engine clarified, throttle body permission removed. · T1 BMW M3 E92 (08-13) Spec Line 1090 removed entirely. · T2 Ford Mustang Boss 302 restrictor opens 56mm to 63mm; Mustang GT 5.0L opens 60mm to 65mm. · T2 Chevrolet Camaro SS/1LE (10-15) minimum weight cut 50 lbs to 3575. · T2 Ford Mustang Challenge Dark Horse R gains 81cc to 5038, weighs 50 lbs more at 3825, runs 315 tyres instead of 295. · T3 and T4 Mazda MX-5 Miata add permitted gearset kit PT#0000-02-6100 to Notes. · T4 MX-5 Miata 19-24 and 16-18, T3 MX-5 16-18 and Global Cup ND1/ND: discontinued DG Motorsports hardtop part #0000-07-5901 removed from permitted list. · T2 Spec Corvette rev limit set to 7100 rpm.showhide
  • T2 TCR Data Points - BoP #40508weight +300 lbsslowerweightT2-TCR all models gain 300 lbs minimum weight; splitter ride height 3.50 inches, chassis 4.0 inches.
  • SM Rear Toe Link #40271wordingwordingSM/SMX Mazda rear toe link part number revised from 0000-04-5361426 to 0000-04-5361.
  • T1 Tire Equality #40342tyres & wheelstyres & wheelsT1 classes now require U-rated or better DOT tires; re-grooving DOT tires banned; shaving and truing only allowed.
  • T2 2023 TCR Hyundais #40278cars addedaddedT2-TCR adds 2023 Hyundai Veloster N TCR and Elantra N TCR, both SEQ transmission, 90% power level, 3000 lbs minimum weight.
  • T1 Trunk Lid Wording #40177wordingwordingT1 trunk lid and wing mounting wording clarified; no performance change.
  • T2 2015+ Ecoboost Mustang #40005weight -100 lbsfasterweightT2 2015–2023 Ecoboost Mustang restrictor removed, tyres to 315, weight cut 100 lbs to 3300.
  • T2 C6 Corvette - All Body Trims Requested #40174aeroaddedaeroT2 Chevrolet Corvette C6 Coupe/Grand Sport gains permission for OEM C6 ZR1 and Z06 carbon splitter and spoiler dimensions.
  • T2 T2-TCR Table Mazda 3 #40209tyres & wheelstyres & wheelsT2-TCR Mazda 3 tyres capped at 275 section width; splitter, valance, ride height rules removed; TCR regulations source simplified.
  • T1 Clarification on Request #39716 T1 (Spec Line #1139) #39924wordingunclearT1 LS1, LS6 removes OEM designation; 70mm restrictor requirement deleted.
  • T1 Mistake in Line 1430 #39958wordingwordingT1 Spec Line Coyote Boss 302 production years corrected to 11–14, displacement 4957 cc unchanged.
  • SM Part Number Change Request #39914otherunclearSM/SMX part number 0000-10-6900 replaced with 0000-06-5016-KT in GCR 9.1.7.C.1.j.1.c.
  • T1 Spec line #1139 Restrictor Change Request #39922enginefasterengineT1 restrictor requirement removed entirely; no replacement specified.
  • T2 14-17 BMW 435i Brake Approval Request #39910suspension & brakessuspension & brakesT2 BMW 435i brakes increased to 370mm front and 345mm rear from 340mm and 330mm.
  • T2 Porsche Cayman S Spec Lines Needed for Atlanta HST #39947wordingwordingT2 Porsche Cayman S year ranges and displacement specs adjusted for 2026 Atlanta HST.
  • T2 Please address loopholes in T2 TCR #40002wordingwordingT2 TCR cars must conform to 2024 TCR Technical Regulations; wheel size capped at 10" x 18", tyres at 275 max width.
  • T1 Replace OEM Heat Exchanger (Intercooler) With Aftermarket #39542aeroaddedaeroT1 GT4 Spec Line 4030- permits Wagner Tuning #200001124 intercooler as replacement for OEM heat exchanger.
  • T2 BMW 240i Permitted Tune #39861wordingremovedT2 BMW M235iR removes alternative tune permission.
  • T1 LS1 into Corvette C6 Spec Line Request #39716cars addedaddedT1 Chevrolet Corvette C6 LS1/LS6 spec line reinstated: 3200 lbs minimum, 70mm restrictor.
  • T2 Request to Add 2014-2017 435i to T2 #38991cars addedaddedBMW 435i 2014–2017 added to T2 at 2979 cc, 40mm restrictor, 3400 lbs minimum weight. BMW M235i restrictor clarified to 40mm TIR.
  • T2 Consideration for Nissan Z & NISMO Z to Touring 2 Class #39296cars addedaddedNissan Z including Nismo added to T2 with 2997cc, 38mm restrictor, 19in wheels, 3600–3650 lbs, 355–381mm brakes.
  • T2 Allow Alt Bushing Material in Toe Links #39607suspension & brakesaddedsuspension & brakesT2-T4 adjustable toe links now allow performance alternative bushings and spherical bearings, previously only spherical bearings permitted.
  • T2 Request for Classification of MG6 TCR in T2-TCR Class #39702cars addedaddedT2-TCR adds Link & Co 03 TCR and MG6 TCR at 3000 lbs, 90% power, sequential, 275 max tyre width.
  • T1 additional T1 adjustment #39520engineremovedengineT1 Spec Line removes 70mm flat plate restrictor option.
  • T2 Alternate Placement of Fuse Panel and Electronics Request #39370otheraddedT2, T3, T4 now allow under-dash electronics relocation for access after roll cage installation.
  • T2 Rebalance Blackwing Cadillac T2 for 2026 #39426weight -50 lbsfasterweightT2 Cadillac CT4-V Blackwing minimum weight drops 50 lbs to 3750.
  • T2 C6 LS2 Corvette Parity Request #39472inductionfasterinductionT2 C6 Corvette LS2 restrictor increases from 67mm to 80mm FPR.
  • T2 T2 Tire Sizing #39490weight -25 lbsfasterweightT2 Dodge Viper SRT10 coupe 03-06 minimum weight cut 25 lbs to 3650.
  • T2 Rear Spoiler for Mustang GT S550 (15-23) #39499aeroaddedaeroT2 Mustang GT 5.0L gains Ford Track/Performance Package rear spoiler aero parts.
  • T2 Clarify T4 Brake Rotor Allowance #39503wordingwordingT4 Performance clarified: 1-piece alternative rotors permitted only at sizes listed in spec line; alternate brake kits may use matching 1-piece rotors.
  • T1 Keep S2000 Classification #39344wordingunclearunclear
  • T1 Correcting and updating T1 GT4 spec lines #39394weight
  • T1 BOP adjustments to non GT4 T1 cars #39406induction +100 lbsfasterinductionT1 non-GT4 cars: multiple restrictor increases 61–80mm range, one weight raise to 3600 lbs, L76 engine clarified, throttle body permission removed.
  • T1 Remove T1 Spec Line #39407removedremovedT1 BMW M3 E92 (08-13) Spec Line 1090 removed entirely.
  • T2 Help the 2011-2014 s197Mustang GT and Boss302 Less Restriction #38523enginefasterengineT2 Ford Mustang Boss 302 restrictor opens 56mm to 63mm; Mustang GT 5.0L opens 60mm to 65mm.
  • T2 Improving Competitiveness of Gen 5 Camaro SS #39021weight -50 lbsfasterweightT2 Chevrolet Camaro SS/1LE (10-15) minimum weight cut 50 lbs to 3575.
  • T2 Adjust T2 Darkhorse R #39346engineslowerengineT2 Ford Mustang Challenge Dark Horse R gains 81cc to 5038, weighs 50 lbs more at 3825, runs 315 tyres instead of 295.
  • T2 ND Gearset Request for T4 #39166otheraddedT3 and T4 Mazda MX-5 Miata add permitted gearset kit PT#0000-02-6100 to Notes.
  • T2 ND Spec Lines Wrong PT#'s #39170removedremovedT4 MX-5 Miata 19-24 and 16-18, T3 MX-5 16-18 and Global Cup ND1/ND: discontinued DG Motorsports hardtop part #0000-07-5901 removed from permitted list.
  • T2 Touring 2 Post-Runoffs BOP Adjustments and Changes #39274induction -50 lbs
  • T2 Adjust rev limit on Spec Corvette in T2 #39282engineslowerengineT2 Spec Corvette rev limit set to 7100 rpm.
Road America Runoffs 20252025-09-292:23.351Kurt Rezzetano · fastest of 11 · top 5 within 3.1s+1.234s (+0.87%)2:23.483Kurt Rezzetano · fastest of 10 · top 5 within 2.9s+0.222s (+0.15%)154.1John Heinricy+4.8 mph (+3.2%)2:20.677James Candelaria · fastest of 5 · top 5 within 5.9s+4.099s (+3.00%)2:21.612Drew Delmonico · fastest of 5 · top 5 within 11.8s+5.481s (+4.03%)163.6Drew Delmonico+5.7 mph (+3.6%)-1.871squal -2.674s98.7%qual 98.1%2:43.111Bobby Gossett · fastest of 32 · top 5 within 0.3s+2.005s (+1.24%)2:44.430Kyle Greenhill · fastest of 28 · top 5 within 0.3s+2.944s (+1.82%)119.3Francisco Barroso-0.6 mph (-0.5%)+20.947squal +19.760s114.6%qual 113.8%
52 rule changes (T2: 29, T1: 19, SM: 4)12 engine · 10 cars added · 7 tyres & wheels · 7 weight · 1 aero · 1 removed · 8 wording · 6 other · T2, T3, T4 spec table header changed from T2 to ET. · BMW M2 CS Cup 2020-2021 in T2 Spec must run Red power stick part #8324085, not Purple #8324089. · T2 Corvette C5 Z06 and C6 brake allowances simplified to stock specifications only. · T2 Chevrolet Corvette C5 LS1 restrictor reduced from 59mm to 58mm FPR. · SMX drivers must submit data acquisition files on time or face suspension and $250 fine. · SMX penalty language clarified: level 1 and 3 infractions may carry $1,000 fines, level 2 and 4 may carry $500 fines. · SM tire marking rules clarified: one Hoosier SM 7.5 P205/50/ZR17 set per Super Tour weekend, impound after first dry session, damaged tires may be replaced with used tires only. · Porsche 981 GT4 Clubsport added to T1 as Spec Line 4085, minimum weight 3100 lbs, 265/645 front and 305/680 rear tires. · T1 Honda S2000 Spec Line 1530 minimum weight drops 50 lbs to 2900. · T1 BMW E46 M3 permits BMW #GS7D36SG sequential transmission as aftermarket option in SL# 1060 and 1070. · T1 BMW M3 E92 minimum weight reduced to 3300 lbs. · T1 Mustang Darkhorse R tyres widen to 315 front and rear, weight set to 3600 lbs with driver, Runoffs eligibility requires 3 Super Tour events. · T2 C6 Corvette LS2 requires 67mm FPR restrictor, up from 63mm. · T2 Nissan 370Z max wheel size increases from 19×10 to 19×10.5 inches. · T2 Cadillac CT4-V Blackwing tire size maximum increases from 295 to 315. · T1 Cadillac CT4-V Blackwing added: 3564cc, 3750 lbs minimum, OEM ECU with reprogramming allowed. · Ford Mustang Challenge Darkhorse R added to T2 with 4957cc engine, 58mm restrictor, 3650 lbs minimum weight. · T2 350Z Spec Line eliminates detailed part numbers and consolidates allowances into cleaner performance criteria. · T1 Mustang Spec 1430 restrictor opens 60mm to 65mm; Spec 1460 weight up to 3500 lbs, restrictor 70mm; Corvette 1190 restrictor 67mm to 70mm; BMW 1090 restrictor tightens 40mm to 35mm, expires 12/31/25; BMW 1100 weight up to 3350 lbs. · BMW M2 CS Cup switches from Purple to Red power stick part #8324085; Corvette C5 Z06 restrictor reduces from 59mm to 58mm. · T1 Mustang weight to 3600 lbs, restrictor to 60mm; Corvette weight to 3500 lbs, restrictor to 67mm; BMW deleted. · T1 E46 M3 Spec Line 1050 throttle body changed from Dinan D760-3400 to VAC Motorsports VAC-TB-S54 on 3.250L engine. · T1 Chevrolet Corvette C8 (2020-2023) minimum weight drops to 3500 lbs. · T1 Chevrolet Camaro Gen 5 required restrictor increases from 75mm to 80mm flat plate. · T1 Audi R8 GT4 Spec Line #4020 max tire size changes to 315 DOT, 305/645, or 30/65-18 (f), 33/68-18 (r) Non-DOT. · T2 Ford Mustang GT 5.0L (15-23) combined with separate restrictors: 63mm for Gen 2, 60mm for Gen 3; 100 lb weight break removed. · T2 Chevrolet Camaro 1LE 1LE gains 100 lbs to 3600, restrictor opens 58mm to 62mm. · T2 BMW M235iR permitted oil cooler, radiator per touring rules, and silicone charge pipe. · Ford SCCA Club Spec Mustang added to T3 at 3350 lbs; Mazda SCCA Club Spec MX-5 added to T4 at 2500 lbs. · T2, T3, T4: nine, nine, and thirty-seven expired spec lines removed effective 2025-01-01. · T2 Ford Mustang GT 5.0L 11-14 minimum weight drops 50 lbs to 3525. · T2 Spec Corvette: SC-3200, SC+-3300; Nankang NS-2R or 295 R compound or any 200tw 315 tire; radiator shroud, brakes, shocks, dry sump, battery, differential, springs now permitted. · SMX OE instrument cluster must stay unmodified and connected; aftermarket dash allowed if wiring only re-routed; alternate gauges now permitted; foot pedal comfort mods allowed without relocation. · T1 GT4 tire sizes standardized: most cars 315 DOT with 305/660 or 305/645 Non-DOT; Camaro 305/680, Mustang 315/680 Non-DOT. · BMW M4 GT4 (G82) added to T1 as spec line 4031, 3525 lbs minimum, red power stick; F82 model switched to red power stick. · T1 now permits 5.5 inch clutch as engine option. · T1 GT4 Spec Line 4020 restrictor opens to 45mm and minimum weight drops to 3400 lbs with driver. · T1 adds Mustang Darkhorse R homologated car, 305/315 tyres, 10.5/11 in wheels, minimum weight TBD. · T1 Corvette may roll or flatten wheel opening lips, remove composite fender lips and liners, and add fender vents for tire clearance. · T1 E46 M3 S54 now allows Dinan Throttle Body #D760-3400 on the 3.250L engine. · T2, T3 Mustang spec lines remove redundant driveshaft allowance notes across six model year ranges. · T2 Chevrolet Corvette C6 LS3 restrictor increased from 53mm to 56mm flat plate. · T2, T3, T4 fuel cell installations may omit charcoal canisters, emissions valves, and sensors. · T2, T3, T4 brake specifications clarified: 2-piece rotors allowed in T2 within 5% OE diameter, T3 within 2% OEM diameter. · T2, T3, T4 fuel cell installations may remove charcoal canisters, emissions valves, and sensors. · Porsche Spec Boxster moves to T4, minimum weight 2750 lbs, ineligible for Runoffs until 3 Super Tour events. · T2 Corvette C6 front wheel width increases to 11 inches, rear to 11 or 13 inches. · T4 BMW 320i Spec Line: Turner Motorsports intercooler #024703TMS02 now allowed. · 2005 Cadillac CTS 3.6L 6-speed manual classified in T3 Spec. · T2 C5 Corvette restrictors now engine-specific: LS1 59mm, LS2 63mm, LS3 56mm FPR. · T2 Chevrolet Corvette Z06 (06-12) Spec Line deleted entirely. · T2 Spec Corvette now allows 295 R compound DOT tire alternative to required Nankang NS-2R.showhide
  • T2 Incorrect Touring Heading #38451wordingwordingT2, T3, T4 spec table header changed from T2 to ET.
  • T2 Clarifications needed to BMW M2 CS cup line #38536wordingwordingBMW M2 CS Cup 2020-2021 in T2 Spec must run Red power stick part #8324085, not Purple #8324089.
  • T2 Fix brake allowance supersessions. #38554otherotherT2 Corvette C5 Z06 and C6 brake allowances simplified to stock specifications only.
  • T2 C5 Corvette correction #38782engineslowerengineT2 Chevrolet Corvette C5 LS1 restrictor reduced from 59mm to 58mm FPR.
  • SM SMX Data Submission - Penalties #38248otheraddedSMX drivers must submit data acquisition files on time or face suspension and $250 fine.
  • SM Committee) SMX Penaly Clarification updated language #38337wordingwordingSMX penalty language clarified: level 1 and 3 infractions may carry $1,000 fines, level 2 and 4 may carry $500 fines.
  • SM Clarify Tire Marking Regs #38005wordingwordingSM tire marking rules clarified: one Hoosier SM 7.5 P205/50/ZR17 set per Super Tour weekend, impound after first dry session, damaged tires may be replaced with used tires only.
  • T1 Acceptance of Porsche 981 GT4 Clubsport into T1 #36664cars addedaddedPorsche 981 GT4 Clubsport added to T1 as Spec Line 4085, minimum weight 3100 lbs, 265/645 front and 305/680 rear tires.
  • T1 Request to Restore T1 Honda S2000 to Proper Weights #37644weight -50 lbsfasterweightT1 Honda S2000 Spec Line 1530 minimum weight drops 50 lbs to 2900.
  • T1 DCT Transmission in E46 #37964cars addedaddedT1 BMW E46 M3 permits BMW #GS7D36SG sequential transmission as aftermarket option in SL# 1060 and 1070.
  • T1 Reduce E92 M3 Minimum Weight to 3050 #38092weightfasterweightT1 BMW M3 E92 minimum weight reduced to 3300 lbs.
  • T1 Finalize Spec Line for T1 Darkhorse #38106tyres & wheelsfastertyres & wheelsT1 Mustang Darkhorse R tyres widen to 315 front and rear, weight set to 3600 lbs with driver, Runoffs eligibility requires 3 Super Tour events.
  • T2 C6 T-2 Corvette 6 Liter Engine Restrictor #37490enginefasterengineT2 C6 Corvette LS2 requires 67mm FPR restrictor, up from 63mm.
  • T2 370Z Mid link Replacement for True Coil Overs and OEM Wheel Size #38014tyres & wheelsfastertyres & wheelsT2 Nissan 370Z max wheel size increases from 19×10 to 19×10.5 inches.
  • T2 T2 Cadillac tire #38210tyres & wheelsfastertyres & wheelsT2 Cadillac CT4-V Blackwing tire size maximum increases from 295 to 315.
  • T1 Cadillac CT4-V Blackwing #38003cars addedaddedT1 Cadillac CT4-V Blackwing added: 3564cc, 3750 lbs minimum, OEM ECU with reprogramming allowed.
  • T2 Please class the Darkhorse R in T2 #37295cars addedaddedFord Mustang Challenge Darkhorse R added to T2 with 4957cc engine, 58mm restrictor, 3650 lbs minimum weight.
  • T2 T2 350Z Spec Line Cleanup #37603wordingwordingT2 350Z Spec Line eliminates detailed part numbers and consolidates allowances into cleaner performance criteria.
  • T1 Correct and make new T1 BOP adjustments. #37737weight +75 lbsslowerweightT1 Mustang Spec 1430 restrictor opens 60mm to 65mm; Spec 1460 weight up to 3500 lbs, restrictor 70mm; Corvette 1190 restrictor 67mm to 70mm; BMW 1090 restrictor tightens 40mm to 35mm, expires 12/31/25; BMW 1100 weight up to 3350 lbs.
  • T2 T2 BOP #37312enginefasterengineBMW M2 CS Cup switches from Purple to Red power stick part #8324085; Corvette C5 Z06 restrictor reduces from 59mm to 58mm.
  • T1 T1 Parity Compared to GT4 #37170weight +125 lbsslowerweightT1 Mustang weight to 3600 lbs, restrictor to 60mm; Corvette weight to 3500 lbs, restrictor to 67mm; BMW deleted.
  • T1 Clarification of Request Approval #37273 #37399engineengineT1 E46 M3 Spec Line 1050 throttle body changed from Dinan D760-3400 to VAC Motorsports VAC-TB-S54 on 3.250L engine.
  • T1 C8 Corvette Facts #37400weight -100 lbsfasterweightT1 Chevrolet Corvette C8 (2020-2023) minimum weight drops to 3500 lbs.
  • T1 Camaro Gen 5 Competitive Disadvantage #37440enginefasterengineT1 Chevrolet Camaro Gen 5 required restrictor increases from 75mm to 80mm flat plate.
  • T1 Tire Changes in the Rules for GT4 #37497tyres & wheelstyres & wheelsT1 Audi R8 GT4 Spec Line #4020 max tire size changes to 315 DOT, 305/645, or 30/65-18 (f), 33/68-18 (r) Non-DOT.
  • T2 Mustang Update backdate #37275enginefasterengineT2 Ford Mustang GT 5.0L (15-23) combined with separate restrictors: 63mm for Gen 2, 60mm for Gen 3; 100 lb weight break removed.
  • T2 BOP Adjustment for 2016 - Camaro SS/1LE #37434weight +100 lbsfasterweightT2 Chevrolet Camaro 1LE 1LE gains 100 lbs to 3600, restrictor opens 58mm to 62mm.
  • T2 BMW M235iR TCS CHANGE REQUEST #37470otheraddedT2 BMW M235iR permitted oil cooler, radiator per touring rules, and silicone charge pipe.
  • T2 Request to Classify Club Spec in Appropriate Touring Classes #37523cars addedaddedFord SCCA Club Spec Mustang added to T3 at 3350 lbs; Mazda SCCA Club Spec MX-5 added to T4 at 2500 lbs.
  • T2 Remove spec lines that have expired #37269removedremovedT2, T3, T4: nine, nine, and thirty-seven expired spec lines removed effective 2025-01-01.
  • T2 BoP for the Various Mustangs #37185weight -50 lbsfasterweightT2 Ford Mustang GT 5.0L 11-14 minimum weight drops 50 lbs to 3525.
  • T2 Spec Corvette Line Clarification. #37441otheraddedT2 Spec Corvette: SC-3200, SC+-3300; Nankang NS-2R or 295 R compound or any 200tw 315 tire; radiator shroud, brakes, shocks, dry sump, battery, differential, springs now permitted.
  • SM E&O SMX Regs 9.1.7.1.D.5.u-.w #37070wordingwordingSMX OE instrument cluster must stay unmodified and connected; aftermarket dash allowed if wiring only re-routed; alternate gauges now permitted; foot pedal comfort mods allowed without relocation.
  • T1 Changes to T1 Tires for GT4 and Other Cars #35383tyres & wheelsunclearT1 GT4 tire sizes standardized: most cars 315 DOT with 305/660 or 305/645 Non-DOT; Camaro 305/680, Mustang 315/680 Non-DOT.
  • T1 G82 M4 GT4 inclusion in T1 #35864cars addedaddedBMW M4 GT4 (G82) added to T1 as spec line 4031, 3525 lbs minimum, red power stick; F82 model switched to red power stick.
  • T1 Alt. Clutch Allowance #36606engineaddedengineT1 now permits 5.5 inch clutch as engine option.
  • T1 BOP Changes Need Updates #36667engine -150 lbsfasterengineT1 GT4 Spec Line 4020 restrictor opens to 45mm and minimum weight drops to 3400 lbs with driver.
  • T1 Request Ford Performance Darkhorse R in T1 #37136cars addedaddedT1 adds Mustang Darkhorse R homologated car, 305/315 tyres, 10.5/11 in wheels, minimum weight TBD.
  • T1 Car Mods for T1 Corvette under line item 1150 #37173aeroaddedaeroT1 Corvette may roll or flatten wheel opening lips, remove composite fender lips and liners, and add fender vents for tire clearance.
  • T1 Increased Bore Throttle Bodies for E46 M3 S54 Engine #37273engineaddedengineT1 E46 M3 S54 now allows Dinan Throttle Body #D760-3400 on the 3.250L engine.
  • T2 Redundant Verbiage Regarding Mustang Spec Lines for Driveshaft #36484wordingwordingT2, T3 Mustang spec lines remove redundant driveshaft allowance notes across six model year ranges.
  • T2 Request Less Restriction for Ls-3 Engined C6 Corvette #36810enginefasterengineT2 Chevrolet Corvette C6 LS3 restrictor increased from 53mm to 56mm flat plate.
  • T2 Fuel Emissions Components #37076otheraddedT2, T3, T4 fuel cell installations may omit charcoal canisters, emissions valves, and sensors.
  • T2 fix brake wording #37129wordingwordingT2, T3, T4 brake specifications clarified: 2-piece rotors allowed in T2 within 5% OE diameter, T3 within 2% OEM diameter.
  • T2 Evaporative emissions systems #37130otheraddedT2, T3, T4 fuel cell installations may remove charcoal canisters, emissions valves, and sensors.
  • T2 Move Spec Boxster to T4 #37158cars addedaddedPorsche Spec Boxster moves to T4, minimum weight 2750 lbs, ineligible for Runoffs until 3 Super Tour events.
  • T2 Corvette Wheels #37169tyres & wheelsfastertyres & wheelsT2 Corvette C6 front wheel width increases to 11 inches, rear to 11 or 13 inches.
  • T2 BMW 320i Spec Line #37204engineaddedengineT4 BMW 320i Spec Line: Turner Motorsports intercooler #024703TMS02 now allowed.
  • T2 Classification for a 2005 Cadillac CTS 3.6 liter 6 speed manual #37224cars addedadded2005 Cadillac CTS 3.6L 6-speed manual classified in T3 Spec.
  • T2 Please Consider Allowing Update to the C5 Corvette #37298engineunclearT2 C5 Corvette restrictors now engine-specific: LS1 59mm, LS2 63mm, LS3 56mm FPR.
  • T2 Major error in lane, but nobody ran it. #37302cars addedremovedcars addedT2 Chevrolet Corvette Z06 (06-12) Spec Line deleted entirely.
  • T2 Spec Corvette Change for T2 #37127tyres & wheelsaddedtyres & wheelsT2 Spec Corvette now allows 295 R compound DOT tire alternative to required Nankang NS-2R.
Road America Runoffs 20242024-10-012:22.117Kurt Rezzetano · fastest of 8 · top 5 within 2.7s-2.078s (-1.44%)2:23.261Kurt Rezzetano · fastest of 7 · top 5 within 3.0s-3.542s (-2.41%)149.3Scotty B White+2.0 mph (+1.3%)2:16.578Andrew Aquilante · fastest of 8 · top 5 within 4.8s-1.068s (-0.78%)2:16.131Andrew Aquilante · fastest of 7 · top 5 within 4.0s-2.570s (-1.85%)157.9Andrew Aquilante-0.8 mph (-0.5%)-7.130squal -5.539s95.0%qual 96.1%2:41.106Ethan Goulart · fastest of 49 · top 5 within 0.5s-1.103s (-0.68%)2:41.486Brett Kowalski · fastest of 43 · top 5 within 0.3s-2.262s (-1.38%)119.9Alex Bertagnoli-1.4 mph (-1.2%)+18.225squal +18.989s112.7%qual 113.4%
48 rule changes (T2: 31, T1: 13, SM: 4)15 cars added · 10 weight · 4 engine · 4 suspension & brakes · 3 tyres & wheels · 2 removed · 1 aero · 1 induction · 6 wording · 2 other · SMX Spec MX-5 camera requirement: non-functioning recorder now will instead of may warrant penalty or disqualification. · SM and SMX must run latest AIM Data Logger Spec MX-5 ECU Protocol, effective 2024-09-01. · SMX Mazda MX-5 OE versus OEM definitions clarified in GCR section 9.1.7.1; wording change only. · SM and SMX now allow an alternate shifter bushing at the bottom of the shift lever. · T2 Subaru Impreza WRX STi (03-07) and (08-11) expiry notes removed, appeal deadline lifted. · T2 Ford Mustang S550 5.0L gains 100 lb weight allowance with 4-piston stock or Brembo 355mm brakes; Ecoboost 2.3 brake weight allowance removed. · T2 Mustang GT 5.0L 15-17 and 2018- now permit Track/Performance Package parts; T3 V6 15-17 clarified to allow Track/Performance package. · T2 Ford Mustang S550 5.0 Gen2/Gen3 loses 100 lbs with 4-piston stock or Brembo brakes, 355mm rotors. · T2-T4 Ford Mustangs: remove 25 lb penalty for non-OEM driveshaft, clarify alternate driveshaft allowance. · T2 Camaro SS, Camaro 1LE, Corvette C5, C6, Z06, Firebird, Solstice GXP now allow four or six piston front calipers. · Audi S4 (2000–2002) classified in T3 with 2671cc, 3400 lbs minimum weight, 38mm restrictor, allowing 800lb springs and intercooler. · Mercedes AMG-C63 S 2023 added to T1 with 4000 cc, 3700 lb minimum weight, no restrictor. · T3 and T4 Mazda RX-8 may remove or disable factory oil injection system. · T2 BMW M3 01-06 maximum wheel size increases from 18 x 9 to 18 x 10 inches. · T2, T3, T4 driveshafts may use carbon fiber, aluminum, or steel; two-piece replaced with one-piece; non-OEM adds 25 lbs. · T1 Honda S2000 classified: 1530 cc max, 2950 lbs minimum, 4.75" supercharger pulley, 6.75" crank pulley. · T2 Porsche Cayman S 06-09 adds StopTech ST60/ST40 brake kit option with 50 lb weight penalty. · T1 adds Pontiac GTO 2006-2009 LS1 5700cc, 3400 lbs minimum, engine repositioning allowed. · T2, T3, T4 Spec Lines remove wheelbase requirement, add Required Restrictor specification. · T2 and T3 Nissan 370Z front brake rotors increase to 355×32 mm, rears to 350×20 mm. · T2 2018+ Mustang GT 5.0L gains BMR rear upper control arm camber links part #UTCA064. · T1 Chevrolet Corvette C8 (2020–23) restrictor plate increases from 70mm to 72mm flat plate. · T1 category removes 23 car spec lines including NSX, Viper, Ferrari, Mazda, Nissan, Porsche, Subaru, Toyota; Porsche 997 spec line 1680 expiration removed. · T2 Ford Mustang GT 5.0L 15-17 permits BMR rear upper control arm camber links part #UTCA064. · T2 Camaro SS, 1LE, Corvette C5, C6, Z06, Firebird, Solstice GXP now allow four or six piston front calipers. · T2 Cadillac CT4-V Blackwing Runoffs eligibility requirement removed. · T2, T3, T4 battery replacement no longer allows alternate manufacturer batteries within 10% OEM weight. · T4 now allows C-Spec touring cars to compete, in addition to existing B-Spec eligibility. · T2, T3, T4 spec lines expire 12/31/24; submit to appeal or cars are removed from class. · T2 Chevrolet Camaro 1LE minimum weight rises to 3575 lbs; restrictor grows to 60mm flat plate. · T1 GT4 cars gain Runoffs eligibility; weights and power maps adjusted across six models; tire rules now allow IMSA or SRO GT4 slicks. · T1 removes 27 spec line numbers entirely, including engine, suspension, brake and aero specifications. · T2 Cadillac CT4-V Blackwing rear wheels widen from 18 x 10 to 18 x 11; sway bars now allowed 35mm front, 30mm rear. · T2 BMW M2 CS Cup minimum weight cut 50 lbs to 3550; M235iR cut 50 lbs to 3300. · T2 Spec Corvette weight drops 175 lbs to 3200; restrictor and ride height requirements removed; Nankang NS-2R tyres now mandatory. · T2 Dodge Viper SRT-10 rear tyre shrinks to 335/30 from 345/30. · T2 Ford Mustang GT 5.0L (11-14) gains 75 lbs to 3575; (15-17) gains 50 lbs to 3650; (18+) gains 50 lbs to 3650. Restrictors enlarged. · T2 Chevrolet Camaro 1LE minimum weight drops to 3500 lbs, restrictor plate increases to 58mm flat. · T2 C5 Z06 gains 56mm restrictor spec; C6 LS2 restrictor opens to 63mm, LS3 to 53mm. · T3 Nissan 370Z now includes model years 2009–2022 with Nismo editions. · T1 Chevrolet Corvette C5 LS2 added: 6000 cc, 3300 lbs minimum, 72mm restrictor, carbon aero option −50 lbs. · T1 adds Chevrolet Corvette C7 (14–19) including Z51, Grandsport as homologated car. · T1 Gen 5 Camaro minimum weight cut 75 lbs to 3475; restrictor opens from 70mm to 75mm flat plate. · T1 Aston Martin Vantage gains OEM Sportshift II transmission as permitted option. · Pontiac GTO 2006-2009 re-integrated to T1 with LS2 at 3400 lbs, 72mm restrictor, or LS3 at 3500 lbs, 61mm restrictor. · T1 Porsche 997-1 GT3 Cup added as spec line 4210, minimum weight 3050 lbs, 996 spec line 1670 removed. · T2 BMW M2 CS Cup 2020- gains permission for hood vents conforming to 9.1.9.2.D.8.a.7.showhide
  • SM SMX Camera Rule Correction #36496wordingwordingSMX Spec MX-5 camera requirement: non-functioning recorder now will instead of may warrant penalty or disqualification.
  • SM Committee) AIM ECU Protocol #36556engineaddedengineSM and SMX must run latest AIM Data Logger Spec MX-5 ECU Protocol, effective 2024-09-01.
  • SM Committee) OE versus OEM Definitons #36608wordingwordingSMX Mazda MX-5 OE versus OEM definitions clarified in GCR section 9.1.7.1; wording change only.
  • SM Committee) Shifter Bushing #36611otheraddedSM and SMX now allow an alternate shifter bushing at the bottom of the shift lever.
  • T2 Errors #36214induction -75 lbs
  • T2 Subaru Appeal #36258wordingwordingT2 Subaru Impreza WRX STi (03-07) and (08-11) expiry notes removed, appeal deadline lifted.
  • T2 S550 Brakes #36571weightslowerweightT2 Ford Mustang S550 5.0L gains 100 lb weight allowance with 4-piston stock or Brembo 355mm brakes; Ecoboost 2.3 brake weight allowance removed.
  • T2 Mustang T2/T3 #35877cars addedaddedT2 Mustang GT 5.0L 15-17 and 2018- now permit Track/Performance Package parts; T3 V6 15-17 clarified to allow Track/Performance package.
  • T2 S550 Brakes #35926weightfasterweightT2 Ford Mustang S550 5.0 Gen2/Gen3 loses 100 lbs with 4-piston stock or Brembo brakes, 355mm rotors.
  • T2 T2-T4 Driveshaft Mistake...? #36050weightfasterweightT2-T4 Ford Mustangs: remove 25 lb penalty for non-OEM driveshaft, clarify alternate driveshaft allowance.
  • T2 request for allowance of 6 piston calipers for T2 C5 corvettes #36126suspension & brakesaddedsuspension & brakesT2 Camaro SS, Camaro 1LE, Corvette C5, C6, Z06, Firebird, Solstice GXP now allow four or six piston front calipers.
  • T2 B8/8.5 Audi S4 T3 and T2 #36195cars addedaddedAudi S4 (2000–2002) classified in T3 with 2671cc, 3400 lbs minimum weight, 38mm restrictor, allowing 800lb springs and intercooler.
  • T1 Please Expedite classing the C63 Mercedes #35987cars addedaddedMercedes AMG-C63 S 2023 added to T1 with 4000 cc, 3700 lb minimum weight, no restrictor.
  • T2 Allow T4 and T3 RX8 to Disable/Remove Factory Oil Inj. #35761engineaddedengineT3 and T4 Mazda RX-8 may remove or disable factory oil injection system.
  • T2 Competition Adjustment Request/Wheel Size of E46 #35895tyres & wheelsfastertyres & wheelsT2 BMW M3 01-06 maximum wheel size increases from 18 x 9 to 18 x 10 inches.
  • T2 Driveshafts #35916weightslowerweightT2, T3, T4 driveshafts may use carbon fiber, aluminum, or steel; two-piece replaced with one-piece; non-OEM adds 25 lbs.
  • T1 Honda S2000 #35582cars addedaddedT1 Honda S2000 classified: 1530 cc max, 2950 lbs minimum, 4.75" supercharger pulley, 6.75" crank pulley.
  • T2 Brake Request for 2009 Porsche Cayman #35723cars addedaddedT2 Porsche Cayman S 06-09 adds StopTech ST60/ST40 brake kit option with 50 lb weight penalty.
  • T1 9.1.9.1 T1 new category item/ line 26 rule to expire Jan 1 2023 #35411cars addedaddedT1 adds Pontiac GTO 2006-2009 LS1 5700cc, 3400 lbs minimum, engine repositioning allowed.
  • T2 Reorganize Spec Lines #35375otheraddedT2, T3, T4 Spec Lines remove wheelbase requirement, add Required Restrictor specification.
  • T2 370Z Brake Rotor Size Correction #35487suspension & brakessuspension & brakesT2 and T3 Nissan 370Z front brake rotors increase to 355×32 mm, rears to 350×20 mm.
  • T2 Letter #35154 2018+ Mustang GT Expansion #35488suspension & brakesaddedsuspension & brakesT2 2018+ Mustang GT 5.0L gains BMR rear upper control arm camber links part #UTCA064.
  • T1 C8 Corvette T1 Restrictor Plate Request #35213enginefasterengineT1 Chevrolet Corvette C8 (2020–23) restrictor plate increases from 70mm to 72mm flat plate.
  • T1 The Cars Have Expired #35379removedremovedT1 category removes 23 car spec lines including NSX, Viper, Ferrari, Mazda, Nissan, Porsche, Subaru, Toyota; Porsche 997 spec line 1680 expiration removed.
  • T2 2015+ Mustang Sway Bar and A-Arm Request #35154suspension & brakesaddedsuspension & brakesT2 Ford Mustang GT 5.0L 15-17 permits BMR rear upper control arm camber links part #UTCA064.
  • T2 Brake Kits #35245cars addedaddedT2 Camaro SS, 1LE, Corvette C5, C6, Z06, Firebird, Solstice GXP now allow four or six piston front calipers.
  • T2 Runoffs wording on Caddy in T2 #35377wordingaddedT2 Cadillac CT4-V Blackwing Runoffs eligibility requirement removed.
  • T2 More Car Lightening Stuff #35319wordingremovedT2, T3, T4 battery replacement no longer allows alternate manufacturer batteries within 10% OEM weight.
  • T2 Inclusion of B-C spec cars in T4 #35374cars addedaddedT4 now allows C-Spec touring cars to compete, in addition to existing B-Spec eligibility.
  • T2 T2-T4 Set expiration dates on spec lines #35378wordingremovedT2, T3, T4 spec lines expire 12/31/24; submit to appeal or cars are removed from class.
  • T2 Reply to letter #35161 and #31661 #35384weight +75 lbsslowerweightT2 Chevrolet Camaro 1LE minimum weight rises to 3575 lbs; restrictor grows to 60mm flat plate.
  • T1 GT4 batch adjustment in T1 #35162cars added -85 lbsaddedT1 GT4 cars gain Runoffs eligibility; weights and power maps adjusted across six models; tire rules now allow IMSA or SRO GT4 slicks.
  • T1 Remove T1 spec lines #35192removedremovedT1 removes 27 spec line numbers entirely, including engine, suspension, brake and aero specifications.
  • T2 Rebalance Blackwing Cadillac T2 #35079tyres & wheelsfastertyres & wheelsT2 Cadillac CT4-V Blackwing rear wheels widen from 18 x 10 to 18 x 11; sway bars now allowed 35mm front, 30mm rear.
  • T2 M2 CS RACING #35130weight -50 lbsfasterweightT2 BMW M2 CS Cup minimum weight cut 50 lbs to 3550; M235iR cut 50 lbs to 3300.
  • T2 Spec Corvette in T2 #35139weight -175 lbsfasterweightT2 Spec Corvette weight drops 175 lbs to 3200; restrictor and ride height requirements removed; Nankang NS-2R tyres now mandatory.
  • T2 T2 Viper BoP #35155tyres & wheelsslowertyres & wheelsT2 Dodge Viper SRT-10 rear tyre shrinks to 335/30 from 345/30.
  • T2 BOP Adjustment for 5.0L Mustangs #35156weight +75 lbsslowerweightT2 Ford Mustang GT 5.0L (11-14) gains 75 lbs to 3575; (15-17) gains 50 lbs to 3650; (18+) gains 50 lbs to 3650. Restrictors enlarged.
  • T2 Take at Look at T-2 BOP #35161weight -50 lbsfasterweightT2 Chevrolet Camaro 1LE minimum weight drops to 3500 lbs, restrictor plate increases to 58mm flat.
  • T2 C5 Corvette Spec Line Oversight #35169enginefasterengineT2 C5 Z06 gains 56mm restrictor spec; C6 LS2 restrictor opens to 63mm, LS3 to 53mm.
  • T2 Requested Update of Model Years of 370Z #35231cars addedaddedT3 Nissan 370Z now includes model years 2009–2022 with Nismo editions.
  • T1 New T1 add spec line for C5 corvette LS2 engines (Copy from C6) #33764cars addedaddedT1 Chevrolet Corvette C5 LS2 added: 6000 cc, 3300 lbs minimum, 72mm restrictor, carbon aero option −50 lbs.
  • T1 C7 Corvette Rule Change Request #34897cars addedaddedT1 adds Chevrolet Corvette C7 (14–19) including Z51, Grandsport as homologated car.
  • T1 Camaro Gen 5 Weight Reduction Due to Competitive Disadvantage #35092weight -75 lbsfasterweightT1 Gen 5 Camaro minimum weight cut 75 lbs to 3475; restrictor opens from 70mm to 75mm flat plate.
  • T1 Addendum to Letter #35022: Drivetrain Rule #35105cars addedaddedT1 Aston Martin Vantage gains OEM Sportshift II transmission as permitted option.
  • T1 2004 - 2006 Pontiac GTO Re-Integration Back Into T1 #34403cars addedaddedPontiac GTO 2006-2009 re-integrated to T1 with LS2 at 3400 lbs, 72mm restrictor, or LS3 at 3500 lbs, 61mm restrictor.
  • T1 Request to Classify Porsche 997-1 GT3 Cup #34561cars addedaddedT1 Porsche 997-1 GT3 Cup added as spec line 4210, minimum weight 3050 lbs, 996 spec line 1670 removed.
  • T2 M2 CS RACING #35122aeroaddedaeroT2 BMW M2 CS Cup 2020- gains permission for hood vents conforming to 9.1.9.2.D.8.a.7.
Virginia International Raceway Runoffs 20232023-09-231:59.504Kurt Rezzetano · fastest of 13 · top 5 within 2.1s-0.772s (-0.64%)2:01.201Kurt Rezzetano · fastest of 13 · top 5 within 1.6s-3.555s (-2.85%)150.7Scotty B White-1.9 mph (-1.2%)1:54.520Andrew Aquilante · fastest of 12 · top 5 within 3.7s-0.370s (-0.32%)1:55.488Andrew Aquilante · fastest of 12 · top 5 within 2.7s-20.579s (-15.12%)159.2James Candelaria+1.6 mph (+1.0%)-5.713squal -4.984s95.3%qual 95.8%2:14.986Danny Steyn · fastest of 52 · top 5 within 0.1s+0.322s (+0.24%)2:16.229Julian DaCosta · fastest of 46 · top 5 within 0.3s-2.878s (-2.07%)120.3Jim Drago+1.1 mph (+0.9%)+15.028squal +15.482s112.4%qual 113.0%
37 rule changes (T2: 17, T1: 19, SM: 1)7 cars added · 6 engine · 5 suspension & brakes · 5 weight · 3 tyres & wheels · 2 aero · 1 induction · 1 removed · 5 wording · 2 other · Chevrolet Camaro GT4-R added to T1 GT4 Spec Line 4035, 315 tires, 3375 lbs minimum, ineligible for Runoffs. · T1 Dodge Viper ACR / SRT RT-10 and ACR/ACR-X spec lines 1350 and 1370 remove 12/23 expiration dates. · T1 GT4 McLaren 570S, Mercedes AMG GT4, and Porsche 718 Cayman GT4 CS MR now eligible for Runoffs competition. · T1 GT4 BMW M4 spec line number changed from 4050 to 4030. · T1 Chevrolet Corvette C5 rear spoiler to 5 inches above bumper allowed, plus 50 lbs; carbon aero parts permitted with 50 lb decrease. · T2 Chevrolet Corvette C6 LS2 restrictor plate increases from 58mm to 60mm flat plate. · T2 Cadillac CT4-V Blackwing permitted to use Radium fuel surge tank with fireproof bulkhead requirement. · Mazda RX-8 T3 and T4 transmission and final drive pairing requirement removed; T4 gains Mazdaspeed radiator, spring kit, restrictor, spoiler, air dam. · T3 BMW 320i 14–15 gains aftermarket intercooler; T4 BMW 320i 14–15 loses it. · T3 and T2 Pontiac Solstice GXP 07-09 minimum ride height set to 3 inches. · T1 Dodge Viper ACR/ACR-X restrictor increases from 50mm to 60mm flat plate. · T1 Dodge Viper ACR/ACR-X Spec Line 1370 restrictor increases to 55mm; Spec Line 1390 decreases to 55mm flat plates. · T1 Ford Mustang S197 (05-14) must use OEM 8.8 differential housing. · T1 Chevrolet Camaro Gen 5 LS7 gains two spec lines with 70mm and 53mm restrictors, both 3450 lbs minimum. · T1 Chevrolet Camaro Gen 5, Corvette C5 and C6: resleeve restricted to stock parameters for engine repair or replacement, not LS3 bore/stroke. · 370Z T2 suspension notes clarified: sway bars now 35mm front/29mm rear, SPL rear toe arms removed, NISMO alternatives added to camber/traction arms and mid-link. · T1 Ford Mustang S197 (05-14) reinstated with 5.0L Voodoo engine, 3550 lbs minimum, 75mm restrictor. · T2 Porsche Cayman S year range extended from 06-08 to 06-09. · T1-GT4 minimum weights set: Aston Martin Vantage AMR 3575 lbs, Audi R8 3550, BMW M4 3500, Ford Mustang 3550, McLaren 570S 3450, Mercedes AMG 3450, Porsche 718 Cayman CS MR 3200, Porsche 718 RS 3450, Toyota Supra 3350. · T1-GT4 McLaren 570S front tyre widens from 285 to 315; Mercedes AMG GT4 front tyre widens from 275 to 315. · T2 C5 Z06 with 56mm restrictor weighs 3425 lbs; 58mm restrictor option removed. · T1 Chevrolet Camaro Gen 5 LS3-6160 adds new Spec Line 1135 with 70mm flat plate restrictor, 3550 lbs minimum weight. · T2 upper and lower control arm bushings can now use polyurethane, delrin, or alternate synthetic material. · T2 Cadillac CT4-V Blackwing now permits adjustable sway bar end links. · T1 aftermarket sequential gearbox cars must have 1:1 or greater top gear ratio, OEM location, max 10 inch bellhousing; non-sequential cars gain 100 lbs weight break. · T1 GT4 all nine cars lose 125 lbs minimum weight with driver across the range. · T1 pre-2023 rules and spec lines removed entirely, effective 2023-03-01. · T2 Honda Civic Type-R tire width increases from 275 to 295. · GT4 McLaren 570S maximum tyre size set to 285 front, 315 rear. · T2 C5 Corvette gains GM Motorsports T1 suspension package and SpecCorvette SCT-1 swaybars. · T2 and T3 Mustang 11-14 may remove upper grille fog lights, replace with mesh or screen. · SM Mazda MX-5 Miata 01-05 minimum weight rises to 2450 lbs, or 2465 with alternate bore. · T1 adds eight GT4 cars: Aston Martin, Audi, BMW, Ford, McLaren, Mercedes, two Porsches, Toyota, minimum weights 3200–3575 lbs, restricted by SRO 2022 rules. · T2 BMW M235iR minimum weight drops 50 lbs to 3350; aftermarket T2 compliant shocks now allowed. · T5 touring class added; T2-T5 cars may race one class up; T5 maximum tyre width 225 with minimum aspect ratio 45. · T2-T5 Touring front and rear suspension maximum negative camber clarified to 3.5 degrees. · T2 Dodge Viper SRT-10 rear wheel widens to 19 x 13, weight increases to 3675 lbs, throttle restrictor hole enlarged to 44mm convertible or 42mm hardtop.showhide
  • T1 Why no Camaro? #34421cars addedaddedChevrolet Camaro GT4-R added to T1 GT4 Spec Line 4035, 315 tires, 3375 lbs minimum, ineligible for Runoffs.
  • T1 Request to Remove Expiration from T1 spec lines #1350 & #1370 #34470wordingwordingT1 Dodge Viper ACR / SRT RT-10 and ACR/ACR-X spec lines 1350 and 1370 remove 12/23 expiration dates.
  • T1 Remove #34475cars addedaddedT1 GT4 McLaren 570S, Mercedes AMG GT4, and Porsche 718 Cayman GT4 CS MR now eligible for Runoffs competition.
  • T1 Error in T1 GT4 numbering scheme- #34578wordingwordingT1 GT4 BMW M4 spec line number changed from 4050 to 4030.
  • T1 C5 Approved Aero That Was Mistakenly Deleted #34374aerosloweraeroT1 Chevrolet Corvette C5 rear spoiler to 5 inches above bumper allowed, plus 50 lbs; carbon aero parts permitted with 50 lb decrease.
  • T2 Corvette LS2 Restrictor Plate Adjustment #34456enginefasterengineT2 Chevrolet Corvette C6 LS2 restrictor plate increases from 58mm to 60mm flat plate.
  • T2 Blacking Cadillac Fuel Capacity #34624otheraddedT2 Cadillac CT4-V Blackwing permitted to use Radium fuel surge tank with fireproof bulkhead requirement.
  • T2 Rules Clarification for Mazda RX8 Spec Line #34395wordingwordingMazda RX-8 T3 and T4 transmission and final drive pairing requirement removed; T4 gains Mazdaspeed radiator, spring kit, restrictor, spoiler, air dam.
  • T2 rule book corrections #34437otheraddedT3 BMW 320i 14–15 gains aftermarket intercooler; T4 BMW 320i 14–15 loses it.
  • T2 Ride Height Correction for the T3 Solstice. #34615suspension & brakessuspension & brakesT3 and T2 Pontiac Solstice GXP 07-09 minimum ride height set to 3 inches.
  • T1 Viper Cleanup #34107inductionfasterinductionT1 Dodge Viper ACR/ACR-X restrictor increases from 50mm to 60mm flat plate.
  • T1 Viper 8300 OEM FPR Size #34268engineunclearT1 Dodge Viper ACR/ACR-X Spec Line 1370 restrictor increases to 55mm; Spec Line 1390 decreases to 55mm flat plates.
  • T1 Ford Mustang S197 (05-14) Clarification #34450wordingwordingT1 Ford Mustang S197 (05-14) must use OEM 8.8 differential housing.
  • T1 Gen 5 Camaro Engine #33875cars addedaddedT1 Chevrolet Camaro Gen 5 LS7 gains two spec lines with 70mm and 53mm restrictors, both 3450 lbs minimum.
  • T1 Inquiry to letter #33682 #34071engineslowerengineT1 Chevrolet Camaro Gen 5, Corvette C5 and C6: resleeve restricted to stock parameters for engine repair or replacement, not LS3 bore/stroke.
  • T2 370Z Obsolete Parts & NISMO Alternatives to SPL Parts #34297suspension & brakessuspension & brakes370Z T2 suspension notes clarified: sway bars now 35mm front/29mm rear, SPL rear toe arms removed, NISMO alternatives added to camber/traction arms and mid-link.
  • T1 Request to reinstate T1 S197 Mustang #34048cars addedaddedT1 Ford Mustang S197 (05-14) reinstated with 5.0L Voodoo engine, 3550 lbs minimum, 75mm restrictor.
  • T2 2009 Porsche Cayman Classing Request #34147cars addedaddedT2 Porsche Cayman S year range extended from 06-08 to 06-09.
  • T1 T1 GT4 adjustments #33786weightunclearT1-GT4 minimum weights set: Aston Martin Vantage AMR 3575 lbs, Audi R8 3550, BMW M4 3500, Ford Mustang 3550, McLaren 570S 3450, Mercedes AMG 3450, Porsche 718 Cayman CS MR 3200, Porsche 718 RS 3450, Toyota Supra 3350.
  • T1 Touring 1 Tire Sizes #34191tyres & wheelsfastertyres & wheelsT1-GT4 McLaren 570S front tyre widens from 285 to 315; Mercedes AMG GT4 front tyre widens from 275 to 315.
  • T2 C5 Z06 Straight Line Speed #33575weightslowerweightT2 C5 Z06 with 56mm restrictor weighs 3425 lbs; 58mm restrictor option removed.
  • T1 Clarification for Camaro Gen5 2010-2015 #33739engineslowerengineT1 Chevrolet Camaro Gen 5 LS3-6160 adds new Spec Line 1135 with 70mm flat plate restrictor, 3550 lbs minimum weight.
  • T2 Allowance of any nonmetallic bushing material in T2 #33833suspension & brakesaddedsuspension & brakesT2 upper and lower control arm bushings can now use polyurethane, delrin, or alternate synthetic material.
  • T2 Allow Adjustable stabilizer bar links #33861suspension & brakesaddedsuspension & brakesT2 Cadillac CT4-V Blackwing now permits adjustable sway bar end links.
  • T1 Sequential Gearbox Limitations in T1 #33691engineaddedengineT1 aftermarket sequential gearbox cars must have 1:1 or greater top gear ratio, OEM location, max 10 inch bellhousing; non-sequential cars gain 100 lbs weight break.
  • T1 T1 GT4 adjustments #33786weightfasterweightT1 GT4 all nine cars lose 125 lbs minimum weight with driver across the range.
  • T1 Sunset of pre 2023 Touring 1 Rules. #33916removedremovedT1 pre-2023 rules and spec lines removed entirely, effective 2023-03-01.
  • T2 Honda Civic Type R Tire Size Increase #33672tyres & wheelsfastertyres & wheelsT2 Honda Civic Type-R tire width increases from 275 to 295.
  • T1 Corrections to T1 Spec Lines #33678tyres & wheelstyres & wheelsGT4 McLaren 570S maximum tyre size set to 285 front, 315 rear.
  • T2 C5 Corvette Swaybars #33269suspension & brakesaddedsuspension & brakesT2 C5 Corvette gains GM Motorsports T1 suspension package and SpecCorvette SCT-1 swaybars.
  • T2 Mustang OEM Grill Request #33333aeroaddedaeroT2 and T3 Mustang 11-14 may remove upper grille fog lights, replace with mesh or screen.
  • SM BOP for NB1 and NB2 #32309weightslowerweightSM Mazda MX-5 Miata 01-05 minimum weight rises to 2450 lbs, or 2465 with alternate bore.
  • T1 GT4 section to Current T1 Rules. #33632cars addedaddedT1 adds eight GT4 cars: Aston Martin, Audi, BMW, Ford, McLaren, Mercedes, two Porsches, Toyota, minimum weights 3200–3575 lbs, restricted by SRO 2022 rules.
  • T2 BMW M235iR/M240iR Aftermarket 2WNR Shocks Allowed - Touring 2 #33464weight -50 lbsfasterweightT2 BMW M235iR minimum weight drops 50 lbs to 3350; aftermarket T2 compliant shocks now allowed.
  • T2 Touring (T2-T5) Category #33617cars addedaddedT5 touring class added; T2-T5 cars may race one class up; T5 maximum tyre width 225 with minimum aspect ratio 45.
  • T2 ENO 9.1.9.2.D.1.e.1.a. #33651wordingwordingT2-T5 Touring front and rear suspension maximum negative camber clarified to 3.5 degrees.
  • T2 Heavy Cars #33345engine +125 lbsfasterengineT2 Dodge Viper SRT-10 rear wheel widens to 19 x 13, weight increases to 3675 lbs, throttle restrictor hole enlarged to 44mm convertible or 42mm hardtop.
Virginia International Raceway Runoffs 20222022-09-242:00.276Kurt Rezzetano · fastest of 14 · top 5 within 1.7s+2.739s (+2.33%)2:04.756Kurt Rezzetano · fastest of 14 · top 5 within 2.0s+6.205s (+5.23%)152.5Aaron Kaplan+3.2 mph (+2.1%)1:54.890Andrew Aquilante · fastest of 10 · top 5 within 3.2s+0.119s (+0.10%)2:16.067Andrew Aquilante · fastest of 8 · top 5 within 15.9s+1.654s (+1.23%)157.5Mark Boden+1.3 mph (+0.8%)+11.311squal -5.386s109.1%qual 95.5%2:14.664Danny Steyn · fastest of 60 · top 5 within 0.2s+0.112s (+0.08%)2:19.107Travis Wiley · fastest of 58 · top 5 within 0.9s+2.648s (+1.94%)119.2Jonathan Neudorf-0.6 mph (-0.5%)+14.351squal +14.388s111.5%qual 112.0%
32 rule changes (T2: 20, T1: 11, SM: 1)8 cars added · 7 weight · 4 engine · 4 suspension & brakes · 1 aero · 1 induction · 6 wording · 1 other · T1 Camaro, CTS, Firebird, GTO minimum weight reduced to 3475 lbs from 3500 lbs. · T1-LP Ford Mustang FP350S restrictor increases from 70mm to 75mm. · Mercedes-Benz AMG GT4 (2017-2021) added to T1 with 3400 lb minimum weight, SRO Power Level 2 engine control. · T2 BMW M235iR/M240iR: 240iR/Evo package penalty removed, EVO package specification clarified. · T2 BMW E92 M3 (08-14) now permits Fall Line Suspension arms for G8X/F8x/E9x M3, E9x M3/E82 1M. · T2-T4 Touring cars with alternative springs now permitted to use performance top hats with spherical bearings on shocks and struts. · T2 BMW E92 M3 (08-14) notes changed from 77 to 78. · Cadillac CT4-V Blackwing added to T2, 3564 cc, 3800 lbs minimum, 18×10/11 wheels, 295 MT tyres, 380/339 mm brakes. · SM Majors must run authorized Penske shock and mount; Regional competitors not required until further evaluation. · T1 Dodge Viper ACR displacement rises to 8400 cc OEM, minimum weight drops to 3550 lbs. · T1 Limited T1 specification reference removed; all T1 cars now have unified allowances. · T1 Mazda RX-7 added: 2700 lbs minimum weight, 44mm restrictor, 13B rotary with single Garrett Turbo #3076. · T2-T4 touring cars model year 2018+ may use aftermarket ECU with 75 lb weight penalty via spec line adjustment. · T2 BMW M2 CS Cup 2020- now allows exhaust part #18302459928 and hot country package parts. · Cadillac CT4-V Blackwing 2022+ added to T2 with 3564 cc engine, 3800 lbs minimum weight, 18×10 front and 18×11 rear wheels, 295 MT tyres. · T1 Cadillac CTS/CTS-V, Chevrolet Camaro, Pontiac Firebird, Pontiac GTO LS3 minimum weight reduced to 3475 lbs. · T1 Camaro, CTS, Firebird, GTO with 7011 max displacement loses 50 lbs, to 3500. · T1 brake rotors no longer limited to 33mm thickness maximum. · T2-T4 grill opening removal for cooling permitted without 16 square inch limit; mesh shape must match factory. · T2 Chevrolet Corvette C6 LS2 restrictor increases from 56 mm to 58 mm. · T2 BMW Z4M 06-08 minimum weight reduced 50 lbs to 3100. · T2 Dodge Viper SRT-10 coupe weight drops to 3550 lbs, throttle restrictor hole shrinks to 41mm. · T2, T3, T4 clarify grill opening removal limited to 16 square inches for radiator cooling; mesh shape must be retained. · T2, T3, T4 radiator and coolant hoses may be replaced with aftermarket options; coolant temp sensor modification permitted. · T2, T3, T4: clarified that 'permitted' or 'allowed' parts in spec lines are alternatives to category rule allowances, not replacements. · T2 Spec Mustang model designation changed to Ford Spec Mustang. · T1 Mazda MX-5 Miata MazdaSpeed minimum weight rises to 2550 lbs, restrictor grows to 42mm. · T1 Chevrolet Corvette Cadillac XLR classified as model year 2019 and earlier. · T2 BMW M2 CS Cup 2020 rear brake rotor minimum thickness reduced from 390 mm to 380 mm. · T4 adds 2014 VW Jetta 1.8T TSI to Spec Lines. · T2 adds 2017+ BMW M2 with 2979cc engine, 10.5x18 wheels, 295 tyres, 3650 lbs minimum weight. · Porsche 911 997.2 GTS (09-12) added to T2 with 60mm flat plate restrictor, 3400 lbs minimum, PDK option at +100 lbs.showhide
  • T1 Correct Camaro Spec Line From Letter #30791 response to 3475lbs #32824weight -25 lbsfasterweightT1 Camaro, CTS, Firebird, GTO minimum weight reduced to 3475 lbs from 3500 lbs.
  • T1 Fix FP350S limited prep and Shelby 350 full prep issues #31680enginefasterengineT1-LP Ford Mustang FP350S restrictor increases from 70mm to 75mm.
  • T1 Request to Classify AMG GT4 #32610cars addedaddedMercedes-Benz AMG GT4 (2017-2021) added to T1 with 3400 lb minimum weight, SRO Power Level 2 engine control.
  • T2 BMW M235iR/M240iR Min Weight Clarification #32430weightfasterweightT2 BMW M235iR/M240iR: 240iR/Evo package penalty removed, EVO package specification clarified.
  • T2 Follow up to Letter 30888 #32477suspension & brakesaddedsuspension & brakesT2 BMW E92 M3 (08-14) now permits Fall Line Suspension arms for G8X/F8x/E9x M3, E9x M3/E82 1M.
  • T2 Request Alternate Front & Rear Strut/Shock Top Hats #32452suspension & brakesaddedsuspension & brakesT2-T4 Touring cars with alternative springs now permitted to use performance top hats with spherical bearings on shocks and struts.
  • T2 Request BoP E92 torque #32456wordingwordingT2 BMW E92 M3 (08-14) notes changed from 77 to 78.
  • T2 Classify Cadillac Blackwing #32535cars addedaddedCadillac CT4-V Blackwing added to T2, 3564 cc, 3800 lbs minimum, 18×10/11 wheels, 295 MT tyres, 380/339 mm brakes.
  • SM Update GCR Section 9.1.7.3.A.1. #32217wordingwordingSM Majors must run authorized Penske shock and mount; Regional competitors not required until further evaluation.
  • T1 Viper/Z06 Parity #31942engine -50 lbsfasterengineT1 Dodge Viper ACR displacement rises to 8400 cc OEM, minimum weight drops to 3550 lbs.
  • T1 Discrepancy in T1 allowances #32293wordingwordingT1 Limited T1 specification reference removed; all T1 cars now have unified allowances.
  • T1 T1 RX7 classification #32352cars addedaddedT1 Mazda RX-7 added: 2700 lbs minimum weight, 44mm restrictor, 13B rotary with single Garrett Turbo #3076.
  • T2 Request to Allow the Use of Aftermarket ECU's in Touring #31067engineaddedengineT2-T4 touring cars model year 2018+ may use aftermarket ECU with 75 lb weight penalty via spec line adjustment.
  • T2 BMW M2 CS Cup 2020- Exhaust #32243engineaddedengineT2 BMW M2 CS Cup 2020- now allows exhaust part #18302459928 and hot country package parts.
  • T2 RequestT2 classification- 2022 Cadillac CT4-V Blackwing #32263cars addedaddedCadillac CT4-V Blackwing 2022+ added to T2 with 3564 cc engine, 3800 lbs minimum weight, 18×10 front and 18×11 rear wheels, 295 MT tyres.
  • T1 Weight reduction E&O #30791weight -25 lbsfasterweightT1 Cadillac CTS/CTS-V, Chevrolet Camaro, Pontiac Firebird, Pontiac GTO LS3 minimum weight reduced to 3475 lbs.
  • T1 Performance Adjustment Request for Camaro #31521weight -50 lbsfasterweightT1 Camaro, CTS, Firebird, GTO with 7011 max displacement loses 50 lbs, to 3500.
  • T1 Remove 33m Brake rotor thickness rule #31954suspension & brakessuspension & brakesT1 brake rotors no longer limited to 33mm thickness maximum.
  • T2 Reply to letter #31486/29879 T2-T4 Grill openings #31935aerofasteraeroT2-T4 grill opening removal for cooling permitted without 16 square inch limit; mesh shape must match factory.
  • T2 C6 Restrictor Help #31995inductionfasterinductionT2 Chevrolet Corvette C6 LS2 restrictor increases from 56 mm to 58 mm.
  • T2 BMW Z4M Adjustment #31885weight -50 lbsfasterweightT2 BMW Z4M 06-08 minimum weight reduced 50 lbs to 3100.
  • T2 Touring 2 BOP adjustments for 2022 #31480weight -50 lbsfasterweightT2 Dodge Viper SRT-10 coupe weight drops to 3550 lbs, throttle restrictor hole shrinks to 41mm.
  • T2 Reply to letter 29879 T2-T4 Grill Openings #31486wordingwordingT2, T3, T4 clarify grill opening removal limited to 16 square inches for radiator cooling; mesh shape must be retained.
  • T2 Request to clarify radiator hoses #31682otheraddedT2, T3, T4 radiator and coolant hoses may be replaced with aftermarket options; coolant temp sensor modification permitted.
  • T2 Clarify Permitted/Allowed #31743wordingwordingT2, T3, T4: clarified that 'permitted' or 'allowed' parts in spec lines are alternatives to category rule allowances, not replacements.
  • T2 SMG #31837wordingwordingT2 Spec Mustang model designation changed to Ford Spec Mustang.
  • T1 Turbo Miata Help #31315weight +200 lbsslowerweightT1 Mazda MX-5 Miata MazdaSpeed minimum weight rises to 2550 lbs, restrictor grows to 42mm.
  • T1 Fix the T1 Corvette heading #31528cars addedaddedT1 Chevrolet Corvette Cadillac XLR classified as model year 2019 and earlier.
  • T2 Typo for BMW M2 CS Cup 2020 #31173suspension & brakessuspension & brakesT2 BMW M2 CS Cup 2020 rear brake rotor minimum thickness reduced from 390 mm to 380 mm.
  • T2 Request to Classify 2014 VW Jetta 1.8t TSI #30436cars addedaddedT4 adds 2014 VW Jetta 1.8T TSI to Spec Lines.
  • T2 Request new car 2017 BMW M2 #30486cars addedaddedT2 adds 2017+ BMW M2 with 2979cc engine, 10.5x18 wheels, 295 tyres, 3650 lbs minimum weight.
  • T2 Request to Classify Porsche 997.2 GTS in T2 (body not = to C2S) #30686cars addedaddedPorsche 911 997.2 GTS (09-12) added to T2 with 60mm flat plate restrictor, 3400 lbs minimum, PDK option at +100 lbs.
Indianapolis Motor Speedway Runoffs 20212021-09-251:47.509Kurt Rezzetano · fastest of 26 · top 5 within 1.6s-1.109s (-1.02%)1:48.474Kurt Rezzetano · fastest of 26 · top 5 within 2.5s-0.295s (-0.27%)151.5Scotty B. White1:42.292Andrew Aquilante · fastest of 22 · top 5 within 1.3s+0.499s (+0.49%)1:43.752Mark Boden · fastest of 22 · top 5 within 1.0s+0.881s (+0.86%)159.2Mark Boden-4.722squal -5.217s95.6%qual 95.1%1:57.695Brian Henderson · fastest of 90 · top 5 within 0.5s-0.611s (-0.52%)1:58.837Brian Henderson · fastest of 88 · top 5 within 0.3s-0.263s (-0.22%)119.8Kyle Greenhill+10.363squal +10.186s109.6%qual 109.5%
49 rule changes (T2: 30, T1: 18, SM: 1)18 cars added · 11 weight · 4 engine · 4 induction · 2 suspension & brakes · 1 tyres & wheels · 7 wording · 2 other · T2 BMW M2 CS Cup 2020- mandatory power stick part number assigned as #8324089. · T1 BMW E46, E36, Z3 minimum weight raised to 2700 lbs; 3.4L engine car to 2750 lbs. · T2 Porsche 911/997.1 (06–08) now permits Cargraphics CARP97DFIFKR alternate exhaust manifold. · T1 Dodge Viper SRT-10 restrictor increases from 45mm to 57mm. · T1 Corvette and Cadillac XLR: Casting #799 heads now permitted on LS6 engines, no other head modifications allowed. · T2 BMW M2 CS Cup 2020- weight increases from 3625 to 3600 lbs; Purple power stick mandatory, hot country package allowed. · T1 Mustang GT5.0L 18+ Performance Pack, Bullet, Mach 1 allowed with 100 lb penalty; Shelby/GT350/GT500 restrictor opens 65 mm to 70 mm. · T1 Dodge Viper SRT-10 Incl. Coupe 08-10 restrictor increases from 45mm to 57mm. · T1 Corvette C7 Grand Sport now included; intake restrictor increases from 70 mm to 73 mm. · T1 Corvette Z06 06-13 now allows aluminum chassis replacement with equivalent OE steel chassis. · T3 Honda Civic Type-R 2020+ allowed brake rotor #45251-TGH-A01 with 25 lb penalty. · T2 Mustang GT 5.0L 15-17 throttle body raised to 58mm, 2018- raised to 55mm. · T2 BMW Z4M 06–08 minimum weight increases 50 lbs, to 3150. · T2 BMW E92M3 weight drops 50 lbs to 3425; intake restrictor shrinks from 80mm to 77mm. · T1 Chevrolet Camaro with 6162 displacement minimum weight reduced to 3500 lbs. · T1-LP Chevrolet Corvette C5 Z06, C6 Grand Sport, and Z06 dry sump kit notes clarified to remove duplicates. · T2 Corvettes C5 Z06, C6, and Z06 gain dry sump kit options and air dam trimming allowances. · T2 Chevrolet Camaro 1LE auto trans: gear ratios and final drive 2.77 specified. · T2 BMW M3 01-06 minimum weight reduced from 3100 lbs to 3000 lbs. · T2 Chevrolet Camaro SS/1LE model years expanded to 2010-2015. · SM adds procedure for CRB-approved obsolete parts and BOP testing in sanctioned events with point forfeiture. · T2-T4 clutch discs and pressure plates must be at least 95% of factory OEM weight, bolted to unmodified stock flywheel. · Spec Corvette added to T2 with 3375 cc, 295 DOT tires, 53 mm restrictor, 3.75 in minimum ride height, 3200 lbs minimum weight. · T2 BMW E92 M3 front and rear spring rate limit raised from 800 to 1000 #/in. · T2 Toyota Supra 2020+ spring rates limited to 800 lb/in front, 1000 lb/in rear. · T1 LP aero adjustments: removed 50 lb weight allowance for stock OEM manifold/headers, reorganised aero and engine durability allowances into numbered list. · T2 BMW M2 CS Cup 2020- permitted to remove door glass and mechanism. · T1 Ford Mustang Challenge maximum displacement changes to 4600 cc for 3-valve engines, 5000 cc for others. · T1 BMW E46 allows carbon or fiberglass OEM-style dashboards with 25 pound weight penalty instead of requiring stock dash pad. · T1 Ford Mustang/Thunderbird specification removed Thunderbird model; now Shelby/Shelby GT350/GT500 only through 2018. · T1 Dodge Viper ACR 8400cc OEM added with 3600 lb minimum weight, 55mm flat-plate restrictor. · BMW M2CS Club Sport added to T1 Spec Lines classification. · Porsche 997.1 GT3 Cup (2006–2011) classified in T1 at 3600cc displacement, 3150 lbs minimum weight, no restrictor. · T2 BMW M235iR gains M240iR/Evo package option with 50 lb penalty and DOT tyre requirement. · Toyota Supra 2020- added to T2 with 2998 cc engine, 3450 lbs minimum weight, 19×10 wheels, 295 tyres. · T2 Honda Civic Type-R gains allowance for PRL cold air intake #PRL PRL-HCR-INT-HVI. · T2 Porsche Carrera S 997.2 (06-08) weight reduced 50 lbs to 3225. · T2 Ford Mustang GT 5.0L 15-17 gear ratios changed to 3.66, 2.43, 1.69, 1.32, 1.00, 0.65 or 4.17, 2.34, 1.52, 1.14, 0.87, 0.69. · T2 BMW Z4M 06-08 maximum wheel size increases from 18×9 to 18×10 inches. · T2 BMW M2 CS Cup 2020- and M235iR (-2016) clarify homologation and touring rule allowances in Notes. · T1 Limited Prep Chevrolet Corvette Z06 years extend to 2013, from 2012. · T2 BMW M2 CS Cup 2020+ classified at 2979 cc, 3625 lbs, 295 tires, 10.5×18 wheels, 380/390 mm brakes. · T2 and T3 Nissan 350Z and 370Z permit 44011-RC350 rear caliper kit and SZ350 rotors; T2 350Z also permits Stillen 400338. · T4 Ford Mustang V6 05-10 allows GT 8.8 rear axle with 3.55 final drive, plus 25 lb penalty. · T3 Scion FR-S/Toyota 86 and Subaru BRZ capped to 2021 model year; T4 models capped to 2021. · T1 Corvette C8 Z51 gets wider wheels and tyres, loses 100 lbs to 3550. · T2 BMW E92 M3 (08-14) minimum weight reduced 50 lbs to 3475; brake, suspension, restrictor and transmission specs clarified with duplicate AP Racing line removed. · T2 Corvette C5 Z06 restrictor sizes increase to 53mm and 58mm; C6 LS2 to 56mm, LS3 to 50mm; Camaro SS/1LE weight drops 75 lbs to 3625; Camaro 1LE restrictor to 56mm; Mustang GT 11-14 to 58mm; 15-17 to 55mm; 2018- to 53mm; Viper restrictor … · T3 Alfa Romeo 4C Launch Edition variant now allowed.showhide
  • T2 BMW M2 CS Power Stick Part Number #31087wordingwordingT2 BMW M2 CS Cup 2020- mandatory power stick part number assigned as #8324089.
  • T1 T1 E46 BOP E&O for Letter # 29970 #30934weight +100 lbsslowerweightT1 BMW E46, E36, Z3 minimum weight raised to 2700 lbs; 3.4L engine car to 2750 lbs.
  • T2 997.1 EO #30933cars addedaddedT2 Porsche 911/997.1 (06–08) now permits Cargraphics CARP97DFIFKR alternate exhaust manifold.
  • T1 Request BoP for the Viper in 1 LP #29968enginefasterengineT1 Dodge Viper SRT-10 restrictor increases from 45mm to 57mm.
  • T1 LS6 Alternative Head Question #30074cars addedaddedT1 Corvette and Cadillac XLR: Casting #799 heads now permitted on LS6 engines, no other head modifications allowed.
  • T2 Request #30406wordingunclearT2 BMW M2 CS Cup 2020- weight increases from 3625 to 3600 lbs; Purple power stick mandatory, hot country package allowed.
  • T1 T1-LP - Add Performance Pack, Bullet, Mach 1 to 18+ Mustang #29849enginefasterengineT1 Mustang GT5.0L 18+ Performance Pack, Bullet, Mach 1 allowed with 100 lb penalty; Shelby/GT350/GT500 restrictor opens 65 mm to 70 mm.
  • T1 Request BoP for the Viper in 1 LP #29968enginefasterengineT1 Dodge Viper SRT-10 Incl. Coupe 08-10 restrictor increases from 45mm to 57mm.
  • T1 Request to classify C7 and 13Viper in T1 LP #29969inductionfasterinductionT1 Corvette C7 Grand Sport now included; intake restrictor increases from 70 mm to 73 mm.
  • T1 Request LP Z06 steel chassis #30589cars addedaddedT1 Corvette Z06 06-13 now allows aluminum chassis replacement with equivalent OE steel chassis.
  • T2 Civic Type R Brake Rotors #29817weightslowerweightT3 Honda Civic Type-R 2020+ allowed brake rotor #45251-TGH-A01 with 25 lb penalty.
  • T2 Mustang S550 Parity in T2 #29925inductionfasterinductionT2 Mustang GT 5.0L 15-17 throttle body raised to 58mm, 2018- raised to 55mm.
  • T2 Request BOP on BMW Z4 T2 car #30597weight +50 lbsslowerweightT2 BMW Z4M 06–08 minimum weight increases 50 lbs, to 3150.
  • T2 E92 #30639weight -50 lbsfasterweightT2 BMW E92M3 weight drops 50 lbs to 3425; intake restrictor shrinks from 80mm to 77mm.
  • T1 Request For Reduction in Weight/Penalties for Camaro #30443weightfasterweightT1 Chevrolet Camaro with 6162 displacement minimum weight reduced to 3500 lbs.
  • T1 Fix dry sump Contradictions in T1-LP vs T2 #30596wordingwordingT1-LP Chevrolet Corvette C5 Z06, C6 Grand Sport, and Z06 dry sump kit notes clarified to remove duplicates.
  • T2 C5/6 Corvette in T1, T1-LP and T2 Dry Sump Standardization #29046otheraddedT2 Corvettes C5 Z06, C6, and Z06 gain dry sump kit options and air dam trimming allowances.
  • T2 Request for Chevrolet Camaro 1LE (2016-) Auto Trans #29067cars addedaddedT2 Chevrolet Camaro 1LE auto trans: gear ratios and final drive 2.77 specified.
  • T2 Request E46 M3 Minimum Competition Weight #29429weight -100 lbsfasterweightT2 BMW M3 01-06 minimum weight reduced from 3100 lbs to 3000 lbs.
  • T2 Request to add 2015 to Chevrolet Camaro SS/1LE 2010-2014 #29736cars addedaddedT2 Chevrolet Camaro SS/1LE model years expanded to 2010-2015.
  • SM Updates - Obsolete Parts & BOP Parts #30438wordingaddedSM adds procedure for CRB-approved obsolete parts and BOP testing in sanctioned events with point forfeiture.
  • T2 Request consistency review in GCR #30263wordingwordingT2-T4 clutch discs and pressure plates must be at least 95% of factory OEM weight, bolted to unmodified stock flywheel.
  • T2 Class Spec Corvette in T2? #30297cars addedaddedSpec Corvette added to T2 with 3375 cc, 295 DOT tires, 53 mm restrictor, 3.75 in minimum ride height, 3200 lbs minimum weight.
  • T2 E92 BMW Spring Rate Request #30391suspension & brakesfastersuspension & brakesT2 BMW E92 M3 front and rear spring rate limit raised from 800 to 1000 #/in.
  • T2 Please correct recent T2 Spec Line #30401suspension & brakessuspension & brakesT2 Toyota Supra 2020+ spring rates limited to 800 lb/in front, 1000 lb/in rear.
  • T1 T1 LP Aero adjustments #30196weightslowerweightT1 LP aero adjustments: removed 50 lb weight allowance for stock OEM manifold/headers, reorganised aero and engine durability allowances into numbered list.
  • T2 Request BMW M2CS door glass removal #30254cars addedaddedT2 BMW M2 CS Cup 2020- permitted to remove door glass and mechanism.
  • T1 Request to Clarify Miller Mustang Classification #28728engineengineT1 Ford Mustang Challenge maximum displacement changes to 4600 cc for 3-valve engines, 5000 cc for others.
  • T1 BMW E46 Carbon Dash #29806weightslowerweightT1 BMW E46 allows carbon or fiberglass OEM-style dashboards with 25 pound weight penalty instead of requiring stock dash pad.
  • T1 Request to Update T1 Mustang Spec Line #30001cars addedremovedcars addedT1 Ford Mustang/Thunderbird specification removed Thunderbird model; now Shelby/Shelby GT350/GT500 only through 2018.
  • T1 Dodge Viper 8400 OEM??? #30174cars addedaddedT1 Dodge Viper ACR 8400cc OEM added with 3600 lb minimum weight, 55mm flat-plate restrictor.
  • T1 Class BMW M2CS Club Sport #30195cars addedaddedBMW M2CS Club Sport added to T1 Spec Lines classification.
  • T1 997.1 GT3 Cup #30229cars addedaddedPorsche 997.1 GT3 Cup (2006–2011) classified in T1 at 3600cc displacement, 3150 lbs minimum weight, no restrictor.
  • T2 Request Addition of BMW M240iR #29503cars addedaddedT2 BMW M235iR gains M240iR/Evo package option with 50 lb penalty and DOT tyre requirement.
  • T2 2021 Toyota Supra #29567cars addedaddedToyota Supra 2020- added to T2 with 2998 cc engine, 3450 lbs minimum weight, 19×10 wheels, 295 tyres.
  • T2 Request Cold Air Intake for Honda Civic Type R #29942inductionaddedinductionT2 Honda Civic Type-R gains allowance for PRL cold air intake #PRL PRL-HCR-INT-HVI.
  • T2 Adjust T2 spec line that was missed in T2 BOP #30055weight -50 lbsfasterweightT2 Porsche Carrera S 997.2 (06-08) weight reduced 50 lbs to 3225.
  • T2 Fix T2 Mustang spec line #30106otherunclearT2 Ford Mustang GT 5.0L 15-17 gear ratios changed to 3.66, 2.43, 1.69, 1.32, 1.00, 0.65 or 4.17, 2.34, 1.52, 1.14, 0.87, 0.69.
  • T2 Z4 Wheel Size #30113tyres & wheelsfastertyres & wheelsT2 BMW Z4M 06-08 maximum wheel size increases from 18×9 to 18×10 inches.
  • T2 Clarify T2 Spec lines #30194wordingwordingT2 BMW M2 CS Cup 2020- and M235iR (-2016) clarify homologation and touring rule allowances in Notes.
  • T1 Correct T1 Limited Prep Years #29708cars addedaddedT1 Limited Prep Chevrolet Corvette Z06 years extend to 2013, from 2012.
  • T2 Request to Classify BMW M2 CS #29523cars addedaddedT2 BMW M2 CS Cup 2020+ classified at 2979 cc, 3625 lbs, 295 tires, 10.5×18 wheels, 380/390 mm brakes.
  • T2 350Z Rear Caliper Replacement #29710cars addedaddedT2 and T3 Nissan 350Z and 370Z permit 44011-RC350 rear caliper kit and SZ350 rotors; T2 350Z also permits Stillen 400338.
  • T2 Request Mustang 8.8” rear axle replacement #29860cars addedaddedT4 Ford Mustang V6 05-10 allows GT 8.8 rear axle with 3.55 final drive, plus 25 lb penalty.
  • T2 Cap year range on all 86s #29908wordingwordingT3 Scion FR-S/Toyota 86 and Subaru BRZ capped to 2021 model year; T4 models capped to 2021.
  • T1 Changes to Corvette C8 #29898weight -100 lbsfasterweightT1 Corvette C8 Z51 gets wider wheels and tyres, loses 100 lbs to 3550.
  • T2 Request to Reevaluate T2 Spec Line for E92 M3 #28266weight -50 lbsfasterweightT2 BMW E92 M3 (08-14) minimum weight reduced 50 lbs to 3475; brake, suspension, restrictor and transmission specs clarified with duplicate AP Racing line removed.
  • T2 Request for Parity Among Vehicles Including S550 Mustang #29486induction -75 lbsfasterinductionT2 Corvette C5 Z06 restrictor sizes increase to 53mm and 58mm; C6 LS2 to 56mm, LS3 to 50mm; Camaro SS/1LE weight drops 75 lbs to 3625; Camaro 1LE restrictor to 56mm; Mustang GT 11-14 to 58mm; 15-17 to 55mm; 2018- to 53mm; Viper restrictor …
  • T2 Alfa Romeo 4C Launch Edition #29531cars addedaddedT3 Alfa Romeo 4C Launch Edition variant now allowed.
Road America Runoffs 20202020-10-022:24.195Alan Kossof · fastest of 15 · top 5 within 2.5s2:26.803Kurt Rezzetano · fastest of 14 · top 5 within 2.2s147.3Mark Boden2:17.646Andrew Aquilante · fastest of 15 · top 5 within 3.7s2:18.701Mark Boden · fastest of 14 · top 5 within 3.0s158.8James Candelaria-8.102squal -6.549s94.5%qual 95.5%2:42.209Kyle Greenhill · fastest of 77 · top 5 within 0.5s2:43.748Preston Pardus · fastest of 75 · top 5 within 1.0s121.3Kyle Greenhill+16.945squal +18.014s111.5%qual 112.5%
45 rule changes (T2: 30, T1: 13, SM: 2)11 cars added · 9 suspension & brakes · 8 weight · 3 aero · 1 engine · 1 tyres & wheels · 7 wording · 5 other · SM allows aftermarket radiators in original location with stock OEM cooling fan, and permits 1990-1997 cars to install upper radiator seal NA75-50-OK7A. · T2 Ford Mustang GT 5.0L and Ecoboost 2.3 sway bar part numbers added to notes: M-FR3A-M8 kit, bars M5490-E or M5490-G. · T2 stock replacement brake rotors now allow 2-piece ferrous disks with aluminum hats, within 5% of OE diameter. · T2 Corvette C-5 Z06 loses 50 lbs to 3425; Camaro SS/1LE loses 50 lbs to 3650; Mustang GT and Boss 302 gain 275 to 295 tyres. · T2 Porsche Cayman S, Spyder 10-12 gains cooler ducting, springs to 800#/in front and 1000#/in rear, rotor ducting, and specific Stop Tech calipers with 343 mm front rotor. · SM rear brake caliper may use single bracket under upper retaining bolt head to prevent pin failure. · T1 rear wing wording clarifies Gurney flap terminology in chord length and mounting height rules. · T2 Ford Mustang EcoBoost and GT 5.0L gain three optional gear ratio sets for competition. · Request to add vehicle to T2, T3, T4 roster; refer to letter #27663 in June 2020 Fastrack for decision. · T2 Porsche Cayman S, Spyder 10-12 gains brake, suspension, steering, and aero upgrades including StopTech calipers, 800#/in front and 1000#/in rear springs, and free sway bars. · T1 and T2 Corvettes now allow coilover suspension with 800 lb max coil springs; T1 Z06 conversion no longer T1-only. · 2004 Mercedes Benz CLK 320 Coupe classified in T4 at 3200 lbs with 3299cc engine, 17-inch wheels, 245 tyres, EIBACH PN# 2563.140 springs allowed. · T1 and T2 Corvettes now allow coilover suspension with 800 lb max coil springs; T1 Z06 conversion no longer T1-only. · T1 Porsche 996 GT3 Cup eligible model years changed from 02-05 to 98-04. · T1 Chevrolet Corvette Cadillac XLR may install SCRSPLR-001 rear spoiler with OE bodywork. · T1 Camaro OEM 366mm rear rotor and caliper allowed without weight penalty. · T2 BMW E92 M3 08-14 adds AP Racing brake kit front 13.01.10038, rear 13.01.10053 to allowed list. · T2 Corvette C5 Z06 weight drops 50 lbs to 3175 with 45mm restrictor, 50 lbs to 3350 with 55mm. · T3 BMW Z3 M & Coupe 98-99 minimum weight reduced to 3150 lbs. · T1 Porsche 996 Spec Lines: 996 Cup Replica Rear deck lid now allowed. · T1 Acura NSX Turbo and Audi TTRS now require DOT tires per GCR section 9.3. · T2 Porsche 911 997 and 997.2 Carrera S require OEM rear deck lid; GT3 Cup front fascia allowed with 75 lb penalty, GT3 Cup splitter banned. · T2 Ford Mustang GT 5.0L 15-17 transmission gear ratios corrected to 3.66, 2.43, 1.69, 1.32, 1.00, 0.65 or 4.69, 2.98, 2.14, 1.76, 1.52, 1.27, 1.00, 0.85, 0.68, 0.63. · T1 BMW E46 and E36 models permitted with S54 engine; displacement corrected to 3250 cc from 3200 cc. · T2 Porsche 911/997 (06-08), 997.2 (09-12), Carrera S (06-08): spoiler, bumper, airdams, rear wing height rules removed. · T1 adds Subaru WRX, WRX STI 2005-2020: 2457 cc, 3000 lbs minimum, 46 mm restrictor, alternate turbo permitted. · T1-LP Ford Mustang FP350S restrictor enlarged to 70mm; GT and GT5.0L weights increased to 3500 lbs, Brembo BBK at no penalty, restrictors removed from notes. · Ford Mustang/Thunderbird 5000 Coyote OEM added to T1; 2015-17 at 3450 lbs, 2018+ at 3450 lbs with 65mm flat plate restrictor. · T1 BMW M3 E92 (08-13) carbon dash allowed with 25 lb penalty added. · T1 Corvette C5 Z06, C6 coupe and Grand Sport, C6 Z06 may convert leaf springs to coilover suspension. · Pontiac Solstice GXP and Saturn Sky move from T2 to T3; wheels widen to 18x9.5, Sky weight drops to 3200 lbs. · T2 ferrous metal two-piece brake rotors allowed, must be within 5% of OE diameter. · Mazda RX-8 Base/R3/Sport/GT (04-12) classified in T3 effective 2020-02-01. · T2 Nissan 370Z gains StopTech brake kit allowance with 50 lb penalty. · T2 Ford Mustang Ecoboost 2.3 loses 100 lbs to 3400, wheels widen to 19 x 11, intercooler and suspension parts allowed. · T2 Mustang GT5.0L (15-17) wheels change to 19 x 11; Brembo BBK 380mm rotors now permitted at no weight penalty instead of +50 lbs. · T2 must have fire system installed; T3 and T4 may have one per GCR 9.3. · T3 Ford Mustang EcoBoost gains three transmission gear ratio options. · T2 Chevrolet Camaro SS 10-14 adds 1LE-SS Track Pack with dry sump, suspension and brake options permitted. · T2 Camaro SS/1LE (10-14) permits 1LE-SS Track Pack, specific suspension, brake, dry sump, and driveshaft parts. · T2 Chevrolet Camaro 1LE 2016- minimum weight cut to 3550 lbs from 3600 lbs. · T2 Honda Civic Type-R 2017- minimum weight drops 50 lbs to 3000; tire TIR spec increases to 51mm. · T3 and T4 Mazda RX-8 Base/R3 (04-12) reclassified to include Sport and GT variants. · Toyota 86 GT variant (2017–) added to T3 and T4 spec lines.showhide
  • SM Radiator E&O Clarifications #29294wordingwordingSM allows aftermarket radiators in original location with stock OEM cooling fan, and permits 1990-1997 cars to install upper radiator seal NA75-50-OK7A.
  • T2 Request 2018+ mustang swaybar update #28659suspension & brakesaddedsuspension & brakesT2 Ford Mustang GT 5.0L and Ecoboost 2.3 sway bar part numbers added to notes: M-FR3A-M8 kit, bars M5490-E or M5490-G.
  • T2 Request to Clarify New 2-piece Brake Rotor Rule #29106otherotherT2 stock replacement brake rotors now allow 2-piece ferrous disks with aluminum hats, within 5% of OE diameter.
  • T2 please consider BoP for the following cars in T2 #29266weight -50 lbsfasterweightT2 Corvette C-5 Z06 loses 50 lbs to 3425; Camaro SS/1LE loses 50 lbs to 3650; Mustang GT and Boss 302 gain 275 to 295 tyres.
  • T2 Request clarification on most recent approval by the Board #29284otheraddedT2 Porsche Cayman S, Spyder 10-12 gains cooler ducting, springs to 800#/in front and 1000#/in rear, rotor ducting, and specific Stop Tech calipers with 343 mm front rotor.
  • SM Modifications to prevent failures of Rear Brake Caliper Pin #28953suspension & brakessuspension & brakesSM rear brake caliper may use single bracket under upper retaining bolt head to prevent pin failure.
  • T1 Touring Gurney flap wicker clarification #29013wordingwordingT1 rear wing wording clarifies Gurney flap terminology in chord length and mounting height rules.
  • T2 Request to correct GCR for 2018+ FORD Mustang GT & Ecoboost #28803otheraddedT2 Ford Mustang EcoBoost and GT 5.0L gain three optional gear ratio sets for competition.
  • T2 Request to Add a Vehicle to the Roster (contd.) #27698wordingunclearRequest to add vehicle to T2, T3, T4 roster; refer to letter #27663 in June 2020 Fastrack for decision.
  • T2 Request brake upgrade and electric power steering pump #28946suspension & brakesfastersuspension & brakesT2 Porsche Cayman S, Spyder 10-12 gains brake, suspension, steering, and aero upgrades including StopTech calipers, 800#/in front and 1000#/in rear springs, and free sway bars.
  • T1 Consider coil spring conversion Corvette in T2 #28824suspension & brakesaddedsuspension & brakesT1 and T2 Corvettes now allow coilover suspension with 800 lb max coil springs; T1 Z06 conversion no longer T1-only.
  • T2 Request to Classify 2004 Mercedes Benz 320 CLK #27663cars addedadded2004 Mercedes Benz CLK 320 Coupe classified in T4 at 3200 lbs with 3299cc engine, 17-inch wheels, 245 tyres, EIBACH PN# 2563.140 springs allowed.
  • T2 Consider coil spring conversion Corvette in T2 #28824suspension & brakesaddedsuspension & brakesT1 and T2 Corvettes now allow coilover suspension with 800 lb max coil springs; T1 Z06 conversion no longer T1-only.
  • T1 Additional Clarification on 996 Cup in T1 From Letter #28040 #28060cars addedaddedT1 Porsche 996 GT3 Cup eligible model years changed from 02-05 to 98-04.
  • T1 Request SPEC Corvette Rear Spolier #28182aeroaddedaeroT1 Chevrolet Corvette Cadillac XLR may install SCRSPLR-001 rear spoiler with OE bodywork.
  • T1 T1 Rear Brake Rotor Size Exemption for Gen 5 Camaro #28402cars addedaddedT1 Camaro OEM 366mm rear rotor and caliper allowed without weight penalty.
  • T2 Please Add the Following BBK to Allowed List for E92 M3 #28421suspension & brakesaddedsuspension & brakesT2 BMW E92 M3 08-14 adds AP Racing brake kit front 13.01.10038, rear 13.01.10053 to allowed list.
  • T2 C5 Weight Adjustment #28433weight -50 lbsfasterweightT2 Corvette C5 Z06 weight drops 50 lbs to 3175 with 45mm restrictor, 50 lbs to 3350 with 55mm.
  • T2 Z3M Roadster Weight #28437weightfasterweightT3 BMW Z3 M & Coupe 98-99 minimum weight reduced to 3150 lbs.
  • T1 Request 996 GT3 Trunk for Wing Allowance. #28153aeroaddedaeroT1 Porsche 996 Spec Lines: 996 Cup Replica Rear deck lid now allowed.
  • T1 All Touring, Change DOT Tire Language 9.1.9.1, 9.3.45 #28452wordingwordingT1 Acura NSX Turbo and Audi TTRS now require DOT tires per GCR section 9.3.
  • T2 Limit Changes to the 997.2 Porsche #28242aerosloweraeroT2 Porsche 911 997 and 997.2 Carrera S require OEM rear deck lid; GT3 Cup front fascia allowed with 75 lb penalty, GT3 Cup splitter banned.
  • T2 Correct T2 Mustang Transmission #28732wordingunclearT2 Ford Mustang GT 5.0L 15-17 transmission gear ratios corrected to 3.66, 2.43, 1.69, 1.32, 1.00, 0.65 or 4.69, 2.98, 2.14, 1.76, 1.52, 1.27, 1.00, 0.85, 0.68, 0.63.
  • T1 Request for E46 wagon with S54 engine in T1 #27427enginefasterengineT1 BMW E46 and E36 models permitted with S54 engine; displacement corrected to 3250 cc from 3200 cc.
  • T2 Request to Readjust the T2 Porsches #27746wordingwordingT2 Porsche 911/997 (06-08), 997.2 (09-12), Carrera S (06-08): spoiler, bumper, airdams, rear wing height rules removed.
  • T1 Request to include Subaru WRX/STI 02-18 in T1 #24916cars addedaddedT1 adds Subaru WRX, WRX STI 2005-2020: 2457 cc, 3000 lbs minimum, 46 mm restrictor, alternate turbo permitted.
  • T1 Request Ford Mustang FP350S T1-LP weight and restrictor change #26662weight +100 lbsfasterweightT1-LP Ford Mustang FP350S restrictor enlarged to 70mm; GT and GT5.0L weights increased to 3500 lbs, Brembo BBK at no penalty, restrictors removed from notes.
  • T1 Request to classify Ford Coyote 3rd Gen OEM #27145cars addedaddedFord Mustang/Thunderbird 5000 Coyote OEM added to T1; 2015-17 at 3450 lbs, 2018+ at 3450 lbs with 65mm flat plate restrictor.
  • T1 Request alternate dashboard #27276otheraddedT1 BMW M3 E92 (08-13) carbon dash allowed with 25 lb penalty added.
  • T1 Request for Allowance of Coil Springs on Limited Prep C6 Corvette #27713suspension & brakesaddedsuspension & brakesT1 Corvette C5 Z06, C6 coupe and Grand Sport, C6 Z06 may convert leaf springs to coilover suspension.
  • T2 Please Switch the Solstice GXP as Specified in T2, to T3 #27413cars added -50 lbsfastercars addedPontiac Solstice GXP and Saturn Sky move from T2 to T3; wheels widen to 18x9.5, Sky weight drops to 3200 lbs.
  • T2 Request for Two Piece Stop Tech Brake Rotors #27582suspension & brakessuspension & brakesT2 ferrous metal two-piece brake rotors allowed, must be within 5% of OE diameter.
  • T2 Request to Classify all Mazda RX8 Models in T3/T4 #27606cars addedaddedMazda RX-8 Base/R3/Sport/GT (04-12) classified in T3 effective 2020-02-01.
  • T2 Request for Alternative Brake Kit on Nissan 370Z #27912suspension & brakesslowersuspension & brakesT2 Nissan 370Z gains StopTech brake kit allowance with 50 lb penalty.
  • T2 2015- Current Ecoboost Mustang #27971weight -100 lbsfasterweightT2 Ford Mustang Ecoboost 2.3 loses 100 lbs to 3400, wheels widen to 19 x 11, intercooler and suspension parts allowed.
  • T2 T2 Mustang #28022tyres & wheelsfastertyres & wheelsT2 Mustang GT5.0L (15-17) wheels change to 19 x 11; Brembo BBK 380mm rotors now permitted at no weight penalty instead of +50 lbs.
  • T2 Clarification of On-Board Fire System for T2 #27183wordingwordingT2 must have fire system installed; T3 and T4 may have one per GCR 9.3.
  • T2 Mustang Ecoboost and GT Transmission #27439cars addedaddedT3 Ford Mustang EcoBoost gains three transmission gear ratio options.
  • T2 Request for Dailey Engineering Dry Sump on 2010 Camaro SS #27514cars addedaddedT2 Chevrolet Camaro SS 10-14 adds 1LE-SS Track Pack with dry sump, suspension and brake options permitted.
  • T2 Request for Half Shafts - 2014 Camaro SS 1LE #27584otheraddedT2 Camaro SS/1LE (10-14) permits 1LE-SS Track Pack, specific suspension, brake, dry sump, and driveshaft parts.
  • T2 Request for Parity Among Vehicles #27665weight -50 lbs
  • T2 Request for 2016-2020 Camaro SS Help #27776weight -50 lbsfasterweightT2 Chevrolet Camaro 1LE 2016- minimum weight cut to 3550 lbs from 3600 lbs.
  • T2 Request for Competitive Adjustments to Honda Civic Type R #27839weight -50 lbsfasterweightT2 Honda Civic Type-R 2017- minimum weight drops 50 lbs to 3000; tire TIR spec increases to 51mm.
  • T2 T4 RX8 Classification Error #27902cars addedaddedT3 and T4 Mazda RX-8 Base/R3 (04-12) reclassified to include Sport and GT variants.
  • T2 Request to add Toyota 86 GT to Spec Line #27910cars addedaddedToyota 86 GT variant (2017–) added to T3 and T4 spec lines.
Virginia International Raceway Runoffs 20192019-10-051:57.537Cooper I MacNeil · fastest of 19 · top 5 within 3.4s1:58.551Cooper I MacNeil · fastest of 18 · top 5 within 2.4s149.4James Leithauser1:54.771Andrew Aquilante · fastest of 19 · top 5 within 3.1s2:14.413Andrew Aquilante · fastest of 15 · top 5 within 4.8s156.2Mark Boden+15.862squal -2.766s113.4%qual 97.6%2:14.552Todd Buras · fastest of 60 · top 5 within 0.2s2:16.459Elivan Goulart · fastest of 56 · top 5 within 0.4s119.8Jim Drago+17.908squal +17.015s115.1%qual 114.5%1:54.469Pete Frost · only car1:57.688Pete Frost · only car145.9Pete Frost-0.863squal -3.068s99.3%qual 97.4%
46 rule changes (T2: 23, T1: 19, SM: 4)12 cars added · 9 suspension & brakes · 6 weight · 2 aero · 2 induction · 1 engine · 1 tyres & wheels · 11 wording · 2 other · T1-LP Chevrolet Camaro 1LE 2016+ minimum weight reduced to 3500 lbs, restrictor increased to 70mm. · T2, T3, T4 spare tire and cover removal wording clarified; removable covers now explicitly allowable to remove. · Ford Mustang Challenge added to T1 as E&O with 4600cc displacement, 3300 lbs minimum weight, no restrictor. · T1 Chevrolet Corvette Cadillac XLR model year range removed from specification. · T1 Cadillac CTS/CTS-V, Chevrolet Camaro, Pontiac Firebird and GTO intake restrictor increases from 67 mm to 70 mm. · T2 Cadillac CTS-V classification expanded from 2006-07 model years to include 2004-05 models. · T2 Cadillac CTS-V 06-07 gains allowance for Hotchkiss sway bars up to 36mm front, 25mm rear. · T2 Cadillac CTS-V 06-07 requires 57mm flat plate restrictor. · T2 Ford Mustang GT 5.0L tire width reduced from 315 to 295. · T2-T4 touring tires must be DOT certified with minimum U speed rating; TCS line size is maximum unless noted. · T2 Audi TT RS 2018+ gains front sway bar to 30mm, rear to 28mm, springs to 1200 lb/in, aftermarket intercooler. · T2 Honda Civic Type-R 2017+ minimum weight rises 150 lbs to 3050, TIR turbo restrictor enlarges 38mm to 50mm. · Ford Mustang with 3.5 EcoBoost engine added to T1: 3496 cc displacement, 3300 lb minimum weight, 31 mm restrictor. · T1 Corvette C5 body allowed C7 carbon aero parts, adds fifty pounds. · T1 Audi TTRS must conform to July 24th, 2015 revision 7 GTS rules, not December 14th, 2011 revision 3. · T1 minimum ride height set to 3.5 inches, measured at rocker panel without driver. · T1 Porsche 928 S4/GTS-R minimum weight drops from 3500 to 3200 lbs; 60mm flat plate restrictor removed. · Porsche 928 S4/928 GTS-R added to T1 at 5400cc, 3500 lbs minimum, 60mm restrictor. · T2 Mustang GT rear anti-roll bar may now be removed or disconnected. · SM fuel pump and filter now permitted as Mazda or OEM equivalent part. · T1-LP Ford Mustang GT 5.0L 2018- classified at 3400 lbs with 65mm restrictor, T2 and T3 Mustangs limited to 2015-2017. · T1-LP Ford Mustang GT 5.0L 2018- classified at 3400 lbs with 65mm restrictor, T2 and T3 Mustangs limited to 2015-2017. · T2 Audi TT RS (2018-) newly classified: 2480cc, 3400 lbs minimum, 19-inch wheels, 275 tires, 371/310mm brakes, 40mm TIR required. · T2 2017+ Civic Type R sway bar rules relaxed: any front/rear up to 30mm allowed, specific HPD parts no longer required. · T4 and T3 Mazda MX-5 hardtop rules clarified: any OEM or aftermarket top permitted if retaining OEM silhouette; specific part numbers listed. · T2, T3, T4 now allow any thermostat serving original equipment intent only. · T2 Ford Mustang Boss 302 (12-13) minimum weight drops to 3500 lbs. · T2 Corvette C6 Coupe/Grand Sport 05-13 front camber maximum 3.0 degrees removed. · T2 Pontiac Firebird and Chevrolet Camaro SS 98-02 permit spring relocation to shock. · T3 and T4 Mazda MX-5 Miata eligibility capped at 2016–2018 model years. · Ford Mustang GT 5.0L 2018+ classified in T2 at 3600 lbs minimum with 50mm restrictor, 19×11 wheels, 315 tyres, specific Ford Performance parts permitted. · SM allows factory Mazda ECU and injector harnesses (P/N 0000-10-020E-99, 0000-10-080D-99) on 1999–2000 model year cars, unmodified. · SM electrical rules reorganized and clarified; alternator now externally regulated only by OEM ECU or master kill switch; harness repair by splicing permitted. · SM tire tread protrusion language removed from GCR 9.1.7.C.5. · T1-LP Mustang GT350(R) spec line replaced with complete dimensions, gearing, brakes, weight 3650 lbs curb, carbon wheels standard. · Ford Mustang FP350S (2017) classified in T1-LP with 3600 lbs minimum weight, 18×11 wheels, 315 tires, 6-speed gears. · T1 suspension rules clarified: spherical bearings, solid or spherical bushings, and alternate control arms now permitted. · T1 Porsche 996 and 996 GT3 Cup lose 150–200 lbs to 3000; 997 loses 50 lbs to 3100. · Porsche 997 T1 Maximum gains PDK transmission option; GT3 Cup engine remains not allowed. · T1 Acura NSX Turbo World Challenge weight rises to 3100 lbs, restrictor shrinks to 44mm. · T1–T4 spec car classifications clarified with permitted parts, rule conformance versions, and exclusions of other touring modifications. · T4 Celica GT wheelbase 2600 and 15x7 wheels added; Forte years narrowed; Fiesta ST starts 2014; Fiat 124 years 16-18 added; battery rule clarified. · T2 Porsche Cayman S/GTS years extended from 13-14 to 13-15, adding 2015 GTS model. · T2 Honda Civic Type-R 2017- allowed Cuztom Tuning FG-CIV16-V3-TR-BK alternate grill. · T1–T4 spec car classifications clarified with permitted parts, rule conformance versions, and exclusions of other touring modifications. · T2–T4 subframe bushings now permitted to be replaced with non-spherical bushings of any material.showhide
  • T1 T1 LP 2016 Camaro and Later #27198weight -100 lbsfasterweightT1-LP Chevrolet Camaro 1LE 2016+ minimum weight reduced to 3500 lbs, restrictor increased to 70mm.
  • T2 Request spare tire/wheel clarification #27012wordingfasterT2, T3, T4 spare tire and cover removal wording clarified; removable covers now explicitly allowable to remove.
  • T1 Request to return Ford Mustang Challenge Car to T1 #26751cars addedaddedFord Mustang Challenge added to T1 as E&O with 4600cc displacement, 3300 lbs minimum weight, no restrictor.
  • T1 Correct years in T1 FP Corvette spec #27023wordingwordingT1 Chevrolet Corvette Cadillac XLR model year range removed from specification.
  • T1 Request BoP Baten - T1 Camaro - Follow up to Letter # 26145 #26900inductionfasterinductionT1 Cadillac CTS/CTS-V, Chevrolet Camaro, Pontiac Firebird and GTO intake restrictor increases from 67 mm to 70 mm.
  • T2 Request to change Cadillac CTS-V years from 06-07 to 04-07 #26842cars addedaddedT2 Cadillac CTS-V classification expanded from 2006-07 model years to include 2004-05 models.
  • T2 Request to allow Hotchkiss front / rear sway bars on T2 CTS-V #26845suspension & brakesaddedsuspension & brakesT2 Cadillac CTS-V 06-07 gains allowance for Hotchkiss sway bars up to 36mm front, 25mm rear.
  • T2 Consider T2 06-07 Cadillac CTS-V BoP #27022inductionslowerinductionT2 Cadillac CTS-V 06-07 requires 57mm flat plate restrictor.
  • T2 Correct T2 Mustang tire size #27024tyres & wheelsslowertyres & wheelsT2 Ford Mustang GT 5.0L tire width reduced from 315 to 295.
  • T1 Clarify DOT tires touring #26556wordingwordingT2-T4 touring tires must be DOT certified with minimum U speed rating; TCS line size is maximum unless noted.
  • T2 2018+ Audi TT RS Suspension Allowances #26631suspension & brakesaddedsuspension & brakesT2 Audi TT RS 2018+ gains front sway bar to 30mm, rear to 28mm, springs to 1200 lb/in, aftermarket intercooler.
  • T2 Request BOP adjustment for 2018 Honda Civic Type R-TIR removal #26882weight +150 lbsfasterweightT2 Honda Civic Type-R 2017+ minimum weight rises 150 lbs to 3050, TIR turbo restrictor enlarges 38mm to 50mm.
  • T1 Request to Classify EcoBoost Mustang #25841cars addedaddedFord Mustang with 3.5 EcoBoost engine added to T1: 3496 cc displacement, 3300 lb minimum weight, 31 mm restrictor.
  • T1 Request Corvette aerodynamic aids #26265aerosloweraeroT1 Corvette C5 body allowed C7 carbon aero parts, adds fifty pounds.
  • T1 Audi TTRS VTS Documentation Revision #26578wordingwordingT1 Audi TTRS must conform to July 24th, 2015 revision 7 GTS rules, not December 14th, 2011 revision 3.
  • T1 Request Ride Height Clarification #26599suspension & brakessuspension & brakesT1 minimum ride height set to 3.5 inches, measured at rocker panel without driver.
  • T1 Opposes Unfair weight and throttle restrictor #26719weight -300 lbsfasterweightT1 Porsche 928 S4/GTS-R minimum weight drops from 3500 to 3200 lbs; 60mm flat plate restrictor removed.
  • T1 Request to classify the Porsche 928GTS/S4 in Touring 1 #26315cars addedaddedPorsche 928 S4/928 GTS-R added to T1 at 5400cc, 3500 lbs minimum, 60mm restrictor.
  • T2 Request for Removal of Rear Anti-roll Bar in T2 Mustang GT #26533suspension & brakesfastersuspension & brakesT2 Mustang GT rear anti-roll bar may now be removed or disconnected.
  • SM Request to allow aftermarket fuel filters. #26370otheraddedSM fuel pump and filter now permitted as Mazda or OEM equivalent part.
  • T1 Request Mustang GT Limited Prep 2018 Classification #24431cars addedaddedT1-LP Ford Mustang GT 5.0L 2018- classified at 3400 lbs with 65mm restrictor, T2 and T3 Mustangs limited to 2015-2017.
  • T2 Request Mustang GT Limited Prep 2018 Classification #24431cars addedaddedT1-LP Ford Mustang GT 5.0L 2018- classified at 3400 lbs with 65mm restrictor, T2 and T3 Mustangs limited to 2015-2017.
  • T2 Request to Classify 2018 Audi TT RS #25961cars addedaddedT2 Audi TT RS (2018-) newly classified: 2480cc, 3400 lbs minimum, 19-inch wheels, 275 tires, 371/310mm brakes, 40mm TIR required.
  • T2 Request for Adjustments on 2017+ Civic Type R #25969suspension & brakessuspension & brakesT2 2017+ Civic Type R sway bar rules relaxed: any front/rear up to 30mm allowed, specific HPD parts no longer required.
  • T2 Correct Mazda MX-5 Hard Top Notes #26137wordingwordingT4 and T3 Mazda MX-5 hardtop rules clarified: any OEM or aftermarket top permitted if retaining OEM silhouette; specific part numbers listed.
  • T2 Consider opening class rules to allow any thermostat #26187engineaddedengineT2, T3, T4 now allow any thermostat serving original equipment intent only.
  • T2 Ford Mustang Boss 302 (12-13) - correct weight #26287weight -50 lbsfasterweightT2 Ford Mustang Boss 302 (12-13) minimum weight drops to 3500 lbs.
  • T2 Request camber correction 005-2013 corvette C6 #26288suspension & brakesremovedsuspension & brakesT2 Corvette C6 Coupe/Grand Sport 05-13 front camber maximum 3.0 degrees removed.
  • T2 Request 98-02 Firebird 98-02 Camaro reloacte rear spring #26291suspension & brakesaddedsuspension & brakesT2 Pontiac Firebird and Chevrolet Camaro SS 98-02 permit spring relocation to shock.
  • T2 Cap 2016 Mazda Miata year at 2018 #26388cars addedremovedcars addedT3 and T4 Mazda MX-5 Miata eligibility capped at 2016–2018 model years.
  • T2 Class Ford Mustang GT 2018+ (reference letter 24431) #26400cars addedaddedFord Mustang GT 5.0L 2018+ classified in T2 at 3600 lbs minimum with 50mm restrictor, 19×11 wheels, 315 tyres, specific Ford Performance parts permitted.
  • SM Request 99-00 replacement Wire harnesses #25602otheraddedSM allows factory Mazda ECU and injector harnesses (P/N 0000-10-020E-99, 0000-10-080D-99) on 1999–2000 model year cars, unmodified.
  • SM Organize and Clarify 9.1.7.C.1.o. #25913wordingwordingSM electrical rules reorganized and clarified; alternator now externally regulated only by OEM ECU or master kill switch; harness repair by splicing permitted.
  • SM Strike Tire Tread Language #26123wordingremovedSM tire tread protrusion language removed from GCR 9.1.7.C.5.
  • T1 Class 2015+ Mustang GT350(R) #21466wordingwordingT1-LP Mustang GT350(R) spec line replaced with complete dimensions, gearing, brakes, weight 3650 lbs curb, carbon wheels standard.
  • T1 Request to Classify Ford FP350S in T1-LP #25341cars addedaddedFord Mustang FP350S (2017) classified in T1-LP with 3600 lbs minimum weight, 18×11 wheels, 315 tires, 6-speed gears.
  • T1 Amendment to Request #25555 #25556suspension & brakessuspension & brakesT1 suspension rules clarified: spherical bearings, solid or spherical bushings, and alternate control arms now permitted.
  • T1 Request to balance 996 v 997 T1 weight #25658weightfasterweightT1 Porsche 996 and 996 GT3 Cup lose 150–200 lbs to 3000; 997 loses 50 lbs to 3100.
  • T1 Request to Add PDK Transmission to 997 Porsche Spec Line #25668cars addedaddedPorsche 997 T1 Maximum gains PDK transmission option; GT3 Cup engine remains not allowed.
  • T1 T1 World Challenge/Grand AM Spec Cars #25687weightslowerweightT1 Acura NSX Turbo World Challenge weight rises to 3100 lbs, restrictor shrinks to 44mm.
  • T1 Add Clarification to Spec Car Classifications Vehicle Spec #25774wordingwordingT1–T4 spec car classifications clarified with permitted parts, rule conformance versions, and exclusions of other touring modifications.
  • T2 Errors, Omissions, and Updates (Various) #22414wordingwordingT4 Celica GT wheelbase 2600 and 15x7 wheels added; Forte years narrowed; Fiesta ST starts 2014; Fiat 124 years 16-18 added; battery rule clarified.
  • T2 Request to classify 2015 Cayman GTS 3.4L in T2 #25335cars addedaddedT2 Porsche Cayman S/GTS years extended from 13-14 to 13-15, adding 2015 GTS model.
  • T2 Request for 2017-2018 Honda Civic Type R - 4 BOP Grill #25513aeroaddedaeroT2 Honda Civic Type-R 2017- allowed Cuztom Tuning FG-CIV16-V3-TR-BK alternate grill.
  • T2 Add Clarification to Spec Car Classifications Vehicle Spec #25774wordingwordingT1–T4 spec car classifications clarified with permitted parts, rule conformance versions, and exclusions of other touring modifications.
  • T2 Clarify Subframe Bushings Permitted for T2-T4 #25800suspension & brakesaddedsuspension & brakesT2–T4 subframe bushings now permitted to be replaced with non-spherical bushings of any material.
Sonoma Raceway Runoffs 20182018-10-101:45.032John Kachadurian · fastest of 30 · top 5 within 2.4s1:45.999John Kachadurian · fastest of 28 · top 5 within 3.0s106.5John Kachadurian1:39.970Kristofer Olson · fastest of 16 · top 5 within 3.8s1:41.125Kristofer Olson · fastest of 15 · top 5 within 3.0s108.6Brad McCall-4.874squal -5.062s95.4%qual 95.2%1:54.355Ken Sutherland · fastest of 48 · top 5 within 0.7s1:55.278Michael Carter · fastest of 48 · top 5 within 0.3s102.2Danny Steyn+9.279squal +9.323s108.8%qual 108.9%1:28.612J R Osborne · fastest of 7 · top 5 within 3.3s1:31.189J R Osborne · fastest of 7 · top 5 within 3.7s140.5J R Osborne-14.810squal -16.420s86.0%qual 84.4%
No rule changes on record between these events
Indianapolis Motor Speedway Runoffs 20172017-09-251:48.618John M Buttermore · fastest of 26 · top 5 within 0.8s1:48.769John M Buttermore · fastest of 25 · top 5 within 1.2s1:41.793Andrew Aquilante · fastest of 22 · top 5 within 2.9s1:42.871Andrew Aquilante · fastest of 21 · top 5 within 2.9s-5.898squal -6.825s94.6%qual 93.7%1:58.306Chris Haldeman · fastest of 86 · top 5 within 0.5s1:59.100Michael Gagliardo · fastest of 83 · top 5 within 0.6s+10.331squal +9.688s109.5%qual 108.9%1:33.746Gary Hickman · fastest of 18 · top 5 within 3.3s1:33.702Alex Mayer · fastest of 17 · top 5 within 3.0s-15.067squal -14.872s86.1%qual 86.3%
No rule changes on record between these events
Mid-Ohio Sports Car Course Runoffs 20162016-09-191:31.563Preston Calvert · fastest of 22 · top 5 within 0.5s1:32.691John M Buttermore · fastest of 20 · top 5 within 1.5s1:28.656Ross Murray · fastest of 17 · top 5 within 1.4s1:29.309Ross Murray · fastest of 15 · top 5 within 1.1s-3.382squal -2.907s96.4%qual 96.8%1:40.514Justin Hille · fastest of 45 · top 5 within 0.3s1:40.764Michael Carter · fastest of 44 · top 5 within 0.3s+8.073squal +8.951s108.7%qual 109.8%1:19.886Alex Mayer · fastest of 10 · top 5 within 1.5s1:21.015Jeremy Hill · fastest of 10 · top 5 within 1.2s-11.676squal -11.677s87.4%qual 87.2%
No rule changes on record between these events
Daytona International Speedway Runoffs 20152015-09-212:00.172Kurt Rezzetano · fastest of 20 · top 5 within 3.2s2:01.077Kurt Rezzetano · fastest of 19 · top 5 within 2.8s1:53.562Andrew Aquilante · fastest of 12 · top 5 within 2.5s1:55.494Andrew Aquilante · fastest of 12 · top 5 within 2.1s-5.583squal -6.610s95.4%qual 94.5%2:18.661Andrew Carbonell · fastest of 62 · top 5 within 0.6s2:24.067Todd Lamb · fastest of 59 · top 5 within 0.8s+22.990squal +18.489s119.0%qual 115.4%1:50.711J R Osborne · fastest of 20 · top 5 within 1.1s1:51.616J R Osborne · fastest of 19 · top 5 within 2.1s-9.461squal -9.461s92.2%qual 92.1%

By track

TrackEvents Typical % of T2 Best Latest 
Road America4100.0%100.0%Runoffs 2020100.0%Runoffs 2026
Virginia International Raceway3100.0%100.0%Runoffs 2019100.0%Runoffs 2023
Indianapolis Motor Speedway2100.0%100.0%Runoffs 2017100.0%Runoffs 2021
Daytona International Speedway1100.0%100.0%Runoffs 2015100.0%Runoffs 2015
Mid-Ohio Sports Car Course1100.0%100.0%Runoffs 2016100.0%Runoffs 2016
Sonoma Raceway1100.0%100.0%Runoffs 2018100.0%Runoffs 2018
About this data
Every event the class ran, at any track, oldest to newest on the chart and newest first in the table. Each point is the class's best lap as a share of T2's best on the same day: the weather and the day cancel out, so one figure compares across years where lap times cannot; a class that suits one track more than another still reads differently there. It still moves when the yardstick's own balance changes or its field thins, and an event the yardstick did not run has no point. A best from fewer than three cars is greyed. The rule changes that took effect between two events are folded between their rows.