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BoP Lab / Classes / P1

P1 vs T2 vs FE2 vs SM pace at every track

Lap times across years say as much about the weather as the class. % of P1 is each class's best lap as a share of P1'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 class · the yardstick the % column and chart are measured against
Tracks · untick to narrow

Quickest here: P1 1:17.308 James Devenport, Runoffs 2016 qualifying · T2 1:31.563 Preston Calvert, Runoffs 2016 qualifying · FE2 1:35.040 Flinn Lazier, Runoffs 2018 qualifying · SM 1:40.514 Justin Hille, Runoffs 2016 qualifying

1:201:402:002:202:4041 rule changes between Runoffs 2018 and Runoffs 201941 ▾38 rule changes between Runoffs 2019 and Runoffs 202038 ▾42 rule changes between Runoffs 2020 and Runoffs 202142 ▾24 rule changes between Runoffs 2021 and Runoffs 202224 ▾25 rule changes between Runoffs 2022 and Runoffs 202325 ▾41 rule changes between Runoffs 2023 and Runoffs 202441 ▾34 rule changes between Runoffs 2024 and Runoffs 202534 ▾29 rule changes between Runoffs 2025 and Runoffs 202629 ▾P1 race best at Runoffs 2015: 1:49.792 (Gianpaolo Ciancimino)Off the chart: P1 race best at Runoffs 2016: 1:19.407 (Gianpaolo Ciancimino)P1 race best at Runoffs 2017: 1:31.499 (Jim Devenport)P1 race best at Runoffs 2018: 1:28.786 (Perry Richardson)P1 race best at Runoffs 2019: 1:43.498 (Todd Slusher)P1 race best at Runoffs 2020: 2:01.870 (James French)P1 race best at Runoffs 2021: 1:29.225 (Lee Alexander)P1 race best at Runoffs 2022: 1:54.095 (John Mcaleer)P1 race best at Runoffs 2023: 1:44.329 (Todd Vanacore)P1 race best at Runoffs 2024: 2:00.418 (Matt Romer)P1 qualifying best at Runoffs 2015: 1:49.219 (Jim Downing)Off the chart: P1 qualifying best at Runoffs 2016: 1:17.308 (James Devenport)P1 qualifying best at Runoffs 2017: 1:30.794 (Jim Devenport)P1 qualifying best at Runoffs 2018: 1:27.714 (Todd Slusher)P1 qualifying best at Runoffs 2019: 1:42.674 (Todd Slusher)P1 qualifying best at Runoffs 2020: 2:01.101 (James French)P1 qualifying best at Runoffs 2021: 1:29.011 (Lee Alexander)P1 qualifying best at Runoffs 2022: 1:41.601 (Todd Slusher)P1 qualifying best at Runoffs 2023: 1:42.602 (Todd Vanacore)P1 qualifying best at Runoffs 2024: 2:00.476 (Chip Romer)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)FE2 race best at Runoffs 2018: 1:35.563 (Flinn Lazier)FE2 race best at Runoffs 2019: 1:52.154 (Liam Snyder)FE2 race best at Runoffs 2020: 2:13.271 (Owen McAllister)FE2 race best at Runoffs 2021: 1:36.655 (Max Grau)FE2 race best at Runoffs 2022: 2:12.045 (Jason Conzo)FE2 race best at Runoffs 2023: 1:51.098 (Franklin Futrelle)FE2 race best at Runoffs 2024: 2:12.748 (Porter Aiken)FE2 race best at Runoffs 2025: 2:13.339 (Franklin Futrelle)FE2 race best at Runoffs 2026: 2:11.881 (Franklin Futrelle)FE2 qualifying best at Runoffs 2018: 1:35.040 (Flinn Lazier)FE2 qualifying best at Runoffs 2019: 1:51.062 (Liam Snyder)FE2 qualifying best at Runoffs 2020: 2:12.806 (Scott Rettich)FE2 qualifying best at Runoffs 2021: 1:36.395 (Max Grau)FE2 qualifying best at Runoffs 2022: 1:50.853 (Charles Russell Turner)FE2 qualifying best at Runoffs 2023: 1:50.665 (Charles Russell Turner)FE2 qualifying best at Runoffs 2024: 2:11.506 (Porter Aiken)FE2 qualifying best at Runoffs 2025: 2:12.475 (Franklin Futrelle)FE2 qualifying best at Runoffs 2026: 2:12.326 (Franklin Futrelle)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)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
P1T2FE2SMsolid race · dashed qualifying · slower is lower
100%110%120%130%41 rule changes between Runoffs 2018 and Runoffs 201941 ▾38 rule changes between Runoffs 2019 and Runoffs 202038 ▾42 rule changes between Runoffs 2020 and Runoffs 202142 ▾24 rule changes between Runoffs 2021 and Runoffs 202224 ▾25 rule changes between Runoffs 2022 and Runoffs 202325 ▾41 rule changes between Runoffs 2023 and Runoffs 202441 ▾34 rule changes between Runoffs 2024 and Runoffs 202534 ▾29 rule changes between Runoffs 2025 and Runoffs 202629 ▾P1 race best at Runoffs 2015: 100.0% of P1's (Gianpaolo Ciancimino)P1 race best at Runoffs 2016: 100.0% of P1's (Gianpaolo Ciancimino)P1 race best at Runoffs 2017: 100.0% of P1's (Jim Devenport)P1 race best at Runoffs 2018: 100.0% of P1's (Perry Richardson)P1 race best at Runoffs 2019: 100.0% of P1's (Todd Slusher)P1 race best at Runoffs 2020: 100.0% of P1's (James French)P1 race best at Runoffs 2021: 100.0% of P1's (Lee Alexander)P1 race best at Runoffs 2022: 100.0% of P1's (John Mcaleer)P1 race best at Runoffs 2023: 100.0% of P1's (Todd Vanacore)P1 race best at Runoffs 2024: 100.0% of P1's (Matt Romer)P1 qualifying best at Runoffs 2015: 100.0% of P1's (Jim Downing)P1 qualifying best at Runoffs 2016: 100.0% of P1's (James Devenport)P1 qualifying best at Runoffs 2017: 100.0% of P1's (Jim Devenport)P1 qualifying best at Runoffs 2018: 100.0% of P1's (Todd Slusher)P1 qualifying best at Runoffs 2019: 100.0% of P1's (Todd Slusher)P1 qualifying best at Runoffs 2020: 100.0% of P1's (James French)P1 qualifying best at Runoffs 2021: 100.0% of P1's (Lee Alexander)P1 qualifying best at Runoffs 2022: 100.0% of P1's (Todd Slusher)P1 qualifying best at Runoffs 2023: 100.0% of P1's (Todd Vanacore)P1 qualifying best at Runoffs 2024: 100.0% of P1's (Chip Romer)T2 race best at Runoffs 2015: 110.3% of P1's (Kurt Rezzetano)T2 race best at Runoffs 2016: 116.7% of P1's (John M Buttermore)T2 race best at Runoffs 2017: 118.9% of P1's (John M Buttermore)T2 race best at Runoffs 2018: 119.4% of P1's (John Kachadurian)T2 race best at Runoffs 2019: 114.5% of P1's (Cooper I MacNeil)T2 race best at Runoffs 2020: 120.5% of P1's (Kurt Rezzetano)T2 race best at Runoffs 2021: 121.6% of P1's (Kurt Rezzetano)T2 race best at Runoffs 2022: 109.3% of P1's (Kurt Rezzetano)T2 race best at Runoffs 2023: 116.2% of P1's (Kurt Rezzetano)T2 race best at Runoffs 2024: 119.0% of P1's (Kurt Rezzetano)T2 qualifying best at Runoffs 2015: 110.0% of P1's (Kurt Rezzetano)T2 qualifying best at Runoffs 2016: 118.4% of P1's (Preston Calvert)T2 qualifying best at Runoffs 2017: 119.6% of P1's (John M Buttermore)T2 qualifying best at Runoffs 2018: 119.7% of P1's (John Kachadurian)T2 qualifying best at Runoffs 2019: 114.5% of P1's (Cooper I MacNeil)T2 qualifying best at Runoffs 2020: 119.1% of P1's (Alan Kossof)T2 qualifying best at Runoffs 2021: 120.8% of P1's (Kurt Rezzetano)T2 qualifying best at Runoffs 2022: 118.4% of P1's (Kurt Rezzetano)T2 qualifying best at Runoffs 2023: 116.5% of P1's (Kurt Rezzetano)T2 qualifying best at Runoffs 2024: 118.0% of P1's (Kurt Rezzetano)FE2 race best at Runoffs 2018: 107.6% of P1's (Flinn Lazier)FE2 race best at Runoffs 2019: 108.4% of P1's (Liam Snyder)FE2 race best at Runoffs 2020: 109.4% of P1's (Owen McAllister)FE2 race best at Runoffs 2021: 108.3% of P1's (Max Grau)FE2 race best at Runoffs 2022: 115.7% of P1's (Jason Conzo)FE2 race best at Runoffs 2023: 106.5% of P1's (Franklin Futrelle)FE2 race best at Runoffs 2024: 110.2% of P1's (Porter Aiken)FE2 qualifying best at Runoffs 2018: 108.4% of P1's (Flinn Lazier)FE2 qualifying best at Runoffs 2019: 108.2% of P1's (Liam Snyder)FE2 qualifying best at Runoffs 2020: 109.7% of P1's (Scott Rettich)FE2 qualifying best at Runoffs 2021: 108.3% of P1's (Max Grau)FE2 qualifying best at Runoffs 2022: 109.1% of P1's (Charles Russell Turner)FE2 qualifying best at Runoffs 2023: 107.9% of P1's (Charles Russell Turner)FE2 qualifying best at Runoffs 2024: 109.2% of P1's (Porter Aiken)SM race best at Runoffs 2015: 131.2% of P1's (Todd Lamb)SM race best at Runoffs 2016: 126.9% of P1's (Michael Carter)SM race best at Runoffs 2017: 130.2% of P1's (Michael Gagliardo)SM race best at Runoffs 2018: 129.8% of P1's (Michael Carter)SM race best at Runoffs 2019: 131.8% of P1's (Elivan Goulart)SM race best at Runoffs 2020: 134.4% of P1's (Preston Pardus)SM race best at Runoffs 2021: 133.2% of P1's (Brian Henderson)SM race best at Runoffs 2022: 121.9% of P1's (Travis Wiley)SM race best at Runoffs 2023: 130.6% of P1's (Julian DaCosta)SM race best at Runoffs 2024: 134.1% of P1's (Brett Kowalski)SM qualifying best at Runoffs 2015: 127.0% of P1's (Andrew Carbonell)SM qualifying best at Runoffs 2016: 130.0% of P1's (Justin Hille)SM qualifying best at Runoffs 2017: 130.3% of P1's (Chris Haldeman)SM qualifying best at Runoffs 2018: 130.4% of P1's (Ken Sutherland)SM qualifying best at Runoffs 2019: 131.0% of P1's (Todd Buras)SM qualifying best at Runoffs 2020: 133.9% of P1's (Kyle Greenhill)SM qualifying best at Runoffs 2021: 132.2% of P1's (Brian Henderson)SM qualifying best at Runoffs 2022: 132.5% of P1's (Danny Steyn)SM qualifying best at Runoffs 2023: 131.6% of P1's (Danny Steyn)SM qualifying best at Runoffs 2024: 133.7% of P1's (Ethan Goulart)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
P1T2FE2SMsolid race · dashed qualifying · each class's best lap as a share of P1's at the same event (the reference class, changeable above); 100% is level, less is quicker, so up the chart is quicker
EventP1T2FE2SM
Qual bestRace bestTrapQual bestRace bestTrapvs P1% of P1Qual bestRace bestTrapvs P1% of P1Qual bestRace bestTrapvs P1% of P1
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%)2:12.326Franklin Futrelle · fastest of 8 · top 5 within 1.9s-0.149s (-0.11%)2:11.881Franklin Futrelle · fastest of 8 · top 5 within 1.6s-1.458s (-1.09%)143.5Steve Whitston-5.5 mph (-3.7%)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%)
29 rule changes (T2: 26, FE2: 1, SM: 2)5 cars added · 5 weight · 3 engine · 2 aero · 2 induction · 2 suspension & brakes · 1 removed · 1 tyres & wheels · 5 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. · T2-TCR adds 2023 Hyundai Veloster N TCR and Elantra N TCR, both SEQ transmission, 90% power level, 3000 lbs minimum weight. · 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. · SM/SMX part number 0000-10-6900 replaced with 0000-06-5016-KT in GCR 9.1.7.C.1.j.1.c. · 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. · T2 BMW M235iR removes alternative tune permission. · 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. · 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. · 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. · FE and FE2 Enterprise bubble tail part WM138014 now allowed; FE2 must use this configuration only.showhide
  • T2 TCR Data Points - BoP #40508weight +300 lbsslower · weightT2-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.
  • 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.
  • T2 2015+ Ecoboost Mustang #40005weight -100 lbsfaster · weightT2 2015–2023 Ecoboost Mustang restrictor removed, tyres to 315, weight cut 100 lbs to 3300.
  • T2 C6 Corvette - All Body Trims Requested #40174aeroadded · aeroT2 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.
  • 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.
  • 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.
  • T2 BMW 240i Permitted Tune #39861wordingremovedT2 BMW M235iR removes alternative tune permission.
  • 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 & brakesadded · suspension & 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.
  • 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 lbsfaster · weightT2 Cadillac CT4-V Blackwing minimum weight drops 50 lbs to 3750.
  • T2 C6 LS2 Corvette Parity Request #39472inductionfaster · inductionT2 C6 Corvette LS2 restrictor increases from 67mm to 80mm FPR.
  • T2 T2 Tire Sizing #39490weight -25 lbsfaster · weightT2 Dodge Viper SRT10 coupe 03-06 minimum weight cut 25 lbs to 3650.
  • T2 Rear Spoiler for Mustang GT S550 (15-23) #39499aeroadded · aeroT2 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.
  • T2 Help the 2011-2014 s197Mustang GT and Boss302 Less Restriction #38523enginefaster · engineT2 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 lbsfaster · weightT2 Chevrolet Camaro SS/1LE (10-15) minimum weight cut 50 lbs to 3575.
  • T2 Adjust T2 Darkhorse R #39346engineslower · engineT2 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 #39282engineslower · engineT2 Spec Corvette rev limit set to 7100 rpm.
  • FE2 FE & FE2 Bubble Tail #38978cars addedaddedFE and FE2 Enterprise bubble tail part WM138014 now allowed; FE2 must use this configuration only.
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%)2:12.475Franklin Futrelle · fastest of 11 · top 5 within 1.4s+0.969s (+0.74%)2:13.339Franklin Futrelle · fastest of 10 · top 5 within 0.6s+0.591s (+0.45%)149.0Steve Whitston+3.7 mph (+2.6%)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%)
34 rule changes (T2: 29, FE2: 1, SM: 4)6 engine · 5 cars added · 4 tyres & wheels · 2 weight · 1 induction · 1 removed · 8 wording · 7 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. · 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. · FE2 allows pre-approved driver safety and comfort seat and control modifications for drivers with disabilities, per logbook. · 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. · 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. · 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 #38782engineslower · engineT2 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.
  • T2 C6 T-2 Corvette 6 Liter Engine Restrictor #37490enginefaster · engineT2 C6 Corvette LS2 requires 67mm FPR restrictor, up from 63mm.
  • T2 370Z Mid link Replacement for True Coil Overs and OEM Wheel Size #38014tyres & wheelsfaster · tyres & wheelsT2 Nissan 370Z max wheel size increases from 19×10 to 19×10.5 inches.
  • T2 T2 Cadillac tire #38210tyres & wheelsfaster · tyres & wheelsT2 Cadillac CT4-V Blackwing tire size maximum increases from 295 to 315.
  • FE2 Driver Safety & Comfort #37965otheraddedFE2 allows pre-approved driver safety and comfort seat and control modifications for drivers with disabilities, per logbook.
  • 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.
  • T2 T2 BOP #37312induction
  • T2 Mustang Update backdate #37275enginefaster · engineT2 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 lbsfaster · weightT2 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 lbsfaster · weightT2 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.
  • 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 #36810enginefaster · engineT2 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 & wheelsfaster · tyres & wheelsT2 Corvette C6 front wheel width increases to 11 inches, rear to 11 or 13 inches.
  • T2 BMW 320i Spec Line #37204engineadded · engineT4 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 addedremoved · cars addedT2 Chevrolet Corvette Z06 (06-12) Spec Line deleted entirely.
  • T2 Spec Corvette Change for T2 #37127tyres & wheelsadded · tyres & wheelsT2 Spec Corvette now allows 295 R compound DOT tire alternative to required Nankang NS-2R.
Road America Runoffs 20242024-10-012:00.476Chip Romer · fastest of 12 · top 5 within 1.5s-0.625s (-0.52%)2:00.418Matt Romer · fastest of 9 · top 5 within 2.1s-1.452s (-1.19%)168.3Jason Miller+8.7 mph (+5.4%)2:22.117Kurt 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%)+22.843squal +21.641s119.0%qual 118.0%2:11.506Porter Aiken · fastest of 18 · top 5 within 0.5s-1.300s (-0.98%)2:12.748Porter Aiken · fastest of 17 · top 5 within 2.0s-0.523s (-0.39%)145.3Porter Aiken+1.9 mph (+1.3%)+12.330squal +11.030s110.2%qual 109.2%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%)+41.068squal +40.630s134.1%qual 133.7%
41 rule changes (P1: 6, T2: 31, SM: 4)11 weight · 6 cars added · 4 suspension & brakes · 3 engine · 3 tyres & wheels · 1 aero · 1 induction · 10 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. · P1 engine approval process wording clarified; unspecified engines need case-by-case Board review. · 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. · T2 Porsche Cayman S 06-09 adds StopTech ST60/ST40 brake kit option with 50 lb weight penalty. · P1 removes redundant effective date language from ECU stall prohibition rule. · P1 Honda K20A-FD2 engine terminology corrected from 'spec' to proper series designation; FIA certification documentation requirement removed. · 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. · 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. · P1 Engine Table line H restrictor grows to 32 mm, weight rises to 1450 lbs; line I restrictor to 31 mm, weight to 1475 lbs. · P1 Group CN Honda K20A-FD2 removes engine modification restrictions; CRB may add intake restrictor if needed. · 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. · 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 #36556engineadded · engineSM 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 #36571weightslower · weightT2 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 #35926weightfaster · weightT2 Ford Mustang S550 5.0 Gen2/Gen3 loses 100 lbs with 4-piston stock or Brembo brakes, 355mm rotors.
  • T2 T2-T4 Driveshaft Mistake...? #36050weightfaster · weightT2-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 & brakesadded · suspension & 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.
  • P1 Update GCR section 9.1.8.B.J.7 #35907wordingwordingP1 engine approval process wording clarified; unspecified engines need case-by-case Board review.
  • T2 Allow T4 and T3 RX8 to Disable/Remove Factory Oil Inj. #35761engineadded · engineT3 and T4 Mazda RX-8 may remove or disable factory oil injection system.
  • T2 Competition Adjustment Request/Wheel Size of E46 #35895tyres & wheelsfaster · tyres & wheelsT2 BMW M3 01-06 maximum wheel size increases from 18 x 9 to 18 x 10 inches.
  • T2 Driveshafts #35916weightslower · weightT2, T3, T4 driveshafts may use carbon fiber, aluminum, or steel; two-piece replaced with one-piece; non-OEM adds 25 lbs.
  • 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.
  • P1 Remove redundant effective date language in GCR 9.1.8.B.J.4 #35693wordingwordingP1 removes redundant effective date language from ECU stall prohibition rule.
  • P1 Correct engine series terminology #35694wordingwordingP1 Honda K20A-FD2 engine terminology corrected from 'spec' to proper series designation; FIA certification documentation requirement removed.
  • 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 & brakesadded · suspension & brakesT2 2018+ Mustang GT 5.0L gains BMR rear upper control arm camber links part #UTCA064.
  • T2 2015+ Mustang Sway Bar and A-Arm Request #35154suspension & brakesadded · suspension & 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 lbsslower · weightT2 Chevrolet Camaro 1LE minimum weight rises to 3575 lbs; restrictor grows to 60mm flat plate.
  • P1 Please correct omitted punctuation #34890weight
  • P1 Adjust restrictors and weights for Engine Table lines H and I #35229weightslower · weightP1 Engine Table line H restrictor grows to 32 mm, weight rises to 1450 lbs; line I restrictor to 31 mm, weight to 1475 lbs.
  • P1 Revise Group CN Honda K20A-FD2 Spec Line #35337wordingunclearP1 Group CN Honda K20A-FD2 removes engine modification restrictions; CRB may add intake restrictor if needed.
  • T2 Rebalance Blackwing Cadillac T2 #35079tyres & wheelsfaster · tyres & 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 lbsfaster · weightT2 BMW M2 CS Cup minimum weight cut 50 lbs to 3550; M235iR cut 50 lbs to 3300.
  • T2 Spec Corvette in T2 #35139weight -175 lbsfaster · weightT2 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 & wheelsslower · tyres & wheelsT2 Dodge Viper SRT-10 rear tyre shrinks to 335/30 from 345/30.
  • T2 BOP Adjustment for 5.0L Mustangs #35156weight +75 lbsslower · weightT2 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 lbsfaster · weightT2 Chevrolet Camaro 1LE minimum weight drops to 3500 lbs, restrictor plate increases to 58mm flat.
  • T2 C5 Corvette Spec Line Oversight #35169enginefaster · engineT2 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.
  • T2 M2 CS RACING #35122aeroadded · aeroT2 BMW M2 CS Cup 2020- gains permission for hood vents conforming to 9.1.9.2.D.8.a.7.
Virginia International Raceway Runoffs 20232023-09-231:42.602Todd Vanacore · fastest of 10 · top 5 within 0.9s+1.001s (+0.99%)1:44.329Todd Vanacore · fastest of 9 · top 5 within 0.7s-9.766s (-8.56%)158.5Jason Miller+1.2 mph (+0.8%)1:59.504Kurt 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%)+16.872squal +16.902s116.2%qual 116.5%1:50.665Charles Russell Turner · fastest of 26 · top 5 within 2.3s-0.188s (-0.17%)1:51.098Franklin Futrelle · fastest of 19 · top 5 within 1.4s-20.947s (-15.86%)141.3Franklin Futrelle-0.6 mph (-0.4%)+6.769squal +8.063s106.5%qual 107.9%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%)+31.900squal +32.384s130.6%qual 131.6%
25 rule changes (P1: 7, T2: 17, SM: 1)5 suspension & brakes · 3 aero · 3 engine · 3 weight · 2 cars added · 1 tyres & wheels · 6 wording · 2 other · 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. · P1 SIR testing: vehicle deemed compliant if it stalls within 3 seconds of the stall test. · P1 intake restrictor rule clarified: flat plate, venturi, or Single Inlet Restrictor required; all intake air must pass through. · P1 ducted air rule clarified: top-exit ducted air must pass through heat exchanger, except cockpit opening and engine bay vents. · 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. · T2 Porsche Cayman S year range extended from 06-08 to 06-09. · T2 C5 Z06 with 56mm restrictor weighs 3425 lbs; 58mm restrictor option removed. · P1 aero height limit, front/rear overhang, and cockpit dimensions corrected to metric-inch equivalents. · 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. · P1 suspension covers must have symmetrical upper and lower surfaces, no airfoil cross-sections or angled downforce. · T2 Honda Civic Type-R tire width increases from 275 to 295. · 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. · 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. · P1 aerodynamic devices may not extend more than 1cm below lower surfaces rear of front axle; body panels covering suspension must not be airfoil-shaped or create downforce. · P1 forced induction prohibited: turbocharging and supercharging not allowed.showhide
  • T2 Corvette LS2 Restrictor Plate Adjustment #34456enginefaster · engineT2 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.
  • P1 SIR Testing #34354wordingwordingP1 SIR testing: vehicle deemed compliant if it stalls within 3 seconds of the stall test.
  • P1 E&O Single Inlet Restrictor abbreviation, etc. #34369wordingwordingP1 intake restrictor rule clarified: flat plate, venturi, or Single Inlet Restrictor required; all intake air must pass through.
  • P1 E&O Clean up ducted air provision #34410wordingwordingP1 ducted air rule clarified: top-exit ducted air must pass through heat exchanger, except cockpit opening and engine bay vents.
  • 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.
  • T2 2009 Porsche Cayman Classing Request #34147cars addedaddedT2 Porsche Cayman S year range extended from 06-08 to 06-09.
  • T2 C5 Z06 Straight Line Speed #33575weightslower · weightT2 C5 Z06 with 56mm restrictor weighs 3425 lbs; 58mm restrictor option removed.
  • P1 E&O - Correct dimensional equivalents #34018wordingwordingP1 aero height limit, front/rear overhang, and cockpit dimensions corrected to metric-inch equivalents.
  • T2 Allowance of any nonmetallic bushing material in T2 #33833suspension & brakesadded · suspension & brakesT2 upper and lower control arm bushings can now use polyurethane, delrin, or alternate synthetic material.
  • T2 Allow Adjustable stabilizer bar links #33861suspension & brakesadded · suspension & brakesT2 Cadillac CT4-V Blackwing now permits adjustable sway bar end links.
  • P1 November 2022 Rules Clarification for Suspension Covers #33615aeroslower · aeroP1 suspension covers must have symmetrical upper and lower surfaces, no airfoil cross-sections or angled downforce.
  • T2 Honda Civic Type R Tire Size Increase #33672tyres & wheelsfaster · tyres & wheelsT2 Honda Civic Type-R tire width increases from 275 to 295.
  • T2 C5 Corvette Swaybars #33269suspension & brakesadded · suspension & brakesT2 C5 Corvette gains GM Motorsports T1 suspension package and SpecCorvette SCT-1 swaybars.
  • T2 Mustang OEM Grill Request #33333aeroadded · aeroT2 and T3 Mustang 11-14 may remove upper grille fog lights, replace with mesh or screen.
  • SM BOP for NB1 and NB2 #32309weightslower · weightSM Mazda MX-5 Miata 01-05 minimum weight rises to 2450 lbs, or 2465 with alternate bore.
  • T2 BMW M235iR/M240iR Aftermarket 2WNR Shocks Allowed - Touring 2 #33464weight -50 lbsfaster · weightT2 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 lbsfaster · engineT2 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.
  • P1 Clarify body panel coverage of suspension components #33318aeroaeroP1 aerodynamic devices may not extend more than 1cm below lower surfaces rear of front axle; body panels covering suspension must not be airfoil-shaped or create downforce.
  • P1 E&O clarification regarding forced induction #33123engineremoved · engineP1 forced induction prohibited: turbocharging and supercharging not allowed.
Virginia International Raceway Runoffs 20222022-09-241:41.601Todd Slusher · fastest of 9 · top 5 within 2.3s-1.073s (-1.05%)1:54.095John Mcaleer · fastest of 9 · top 5 within 1.4s+10.597s (+10.24%)157.2Jason Miller+1.3 mph (+0.8%)2:00.276Kurt 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%)+10.661squal +18.675s109.3%qual 118.4%1:50.853Charles Russell Turner · fastest of 25 · top 5 within 1.1s-0.209s (-0.19%)2:12.045Jason Conzo · fastest of 22 · top 5 within 1.8s+19.891s (+17.74%)141.9Eric Cruz-0.6 mph (-0.5%)+17.950squal +9.252s115.7%qual 109.1%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%)+25.012squal +33.063s121.9%qual 132.5%
24 rule changes (P1: 3, T2: 20, SM: 1)5 cars added · 4 engine · 3 suspension & brakes · 3 weight · 1 aero · 1 induction · 6 wording · 1 other · P1 motorcycle-based engines with individual throttle bodies must use flat plate intake restrictors within 4 inches of primary butterfly. · 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. · P1 bodywork rules clarified: cycle fenders prohibited, side body minimum height at front axle centerline, air ducting for downforce banned. · 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. · 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. · 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. · P1 2-cycle 6-cylinder maximum displacement increases to 1725 cc, restrictor shrinks to 40mm, minimum weight drops to 1275 lbs. · 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. · 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
  • P1 Clarify authorization to use flat plate intake restrictor #32964engineadded · engineP1 motorcycle-based engines with individual throttle bodies must use flat plate intake restrictors within 4 inches of primary butterfly.
  • T2 BMW M235iR/M240iR Min Weight Clarification #32430weightfaster · weightT2 BMW M235iR/M240iR: 240iR/Evo package penalty removed, EVO package specification clarified.
  • T2 Follow up to Letter 30888 #32477suspension & brakesadded · suspension & brakesT2 BMW E92 M3 (08-14) now permits Fall Line Suspension arms for G8X/F8x/E9x M3, E9x M3/E82 1M.
  • P1 E&O Clarification of Bodywork Rules #32468wordingwordingP1 bodywork rules clarified: cycle fenders prohibited, side body minimum height at front axle centerline, air ducting for downforce banned.
  • T2 Request Alternate Front & Rear Strut/Shock Top Hats #32452suspension & brakesadded · suspension & 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.
  • T2 Request to Allow the Use of Aftermarket ECU's in Touring #31067engineadded · engineT2-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 #32243engineadded · engineT2 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.
  • T2 Reply to letter #31486/29879 T2-T4 Grill openings #31935aerofaster · aeroT2-T4 grill opening removal for cooling permitted without 16 square inch limit; mesh shape must match factory.
  • T2 C6 Restrictor Help #31995inductionfaster · inductionT2 Chevrolet Corvette C6 LS2 restrictor increases from 56 mm to 58 mm.
  • T2 BMW Z4M Adjustment #31885weight -50 lbsfaster · weightT2 BMW Z4M 06-08 minimum weight reduced 50 lbs to 3100.
  • P1 Displacement & Weight Change Request for 2-Cycle 6 Cylinder #31609enginefaster · engineP1 2-cycle 6-cylinder maximum displacement increases to 1725 cc, restrictor shrinks to 40mm, minimum weight drops to 1275 lbs.
  • T2 Touring 2 BOP adjustments for 2022 #31480weight -50 lbsfaster · weightT2 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.
  • 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 20212021-09-251:29.011Lee Alexander · fastest of 13 · top 5 within 2.5s-1.783s (-1.96%)1:29.225Lee Alexander · fastest of 12 · top 5 within 3.5s-2.274s (-2.49%)160.1Jason Miller1:47.509Kurt 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. White+19.249squal +18.498s121.6%qual 120.8%1:36.395Max Grau · fastest of 28 · top 5 within 0.7s1:36.655Max Grau · fastest of 28 · top 5 within 0.7s146.2Gray Fowler+7.430squal +7.384s108.3%qual 108.3%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+29.612squal +28.684s133.2%qual 132.2%
42 rule changes (P1: 11, T2: 30, SM: 1)13 cars added · 6 weight · 3 induction · 2 engine · 2 suspension & brakes · 1 tyres & wheels · 13 wording · 2 other · P1 creates separate spec lines H and I for 2000cc and 2300cc engines at 1400 and 1445 lbs minimum weight respectively. · P1 Staudacher may run 950 lbs minimum weight with 38.5mm flat plate intake restrictor, removing prior weight-linked restrictor rule. · T2 BMW M2 CS Cup 2020- mandatory power stick part number assigned as #8324089. · P1 adds 1355cc motorcycle-based engine line C at 1075 lbs minimum weight, no restrictor required. · T2 Porsche 911/997.1 (06–08) now permits Cargraphics CARP97DFIFKR alternate exhaust manifold. · T2 BMW M2 CS Cup 2020- weight increases from 3625 to 3600 lbs; Purple power stick mandatory, hot country package allowed. · 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. · P1 cockpit opening section allows tonneau covers to meet minimum dimensions; wording clarified on equipment attachment. · P1 Staudacher 1005cc homologated before 1-1-2014 may run 38.5mm flat plate intake restrictor at 950 lbs minimum weight. · P1 Spec Line C: FPIR not required at 1150 lbs, 1355cc max may run without FPIR at 1075 lbs. Spec Line G: up to 2000cc runs 30mm SIR at 1400 lbs, 2300cc runs 30mm SIR at 1445 lbs. · P1 classes B, C, D maximum valves per cylinder set to 4, previously unspecified. · 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. · P1 Spec Line A clarifies carburetor induction only, one per cylinder, balance tubes not allowed. · P1 Spec Line H notes clarify peripheral port or bridgeport allowed; wording only. · 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. · P1 Elan DP02-spec Mazda MZR sealed engine option removed effective 3/1/2021. · P1 Engine Table Spec Lines C and G change 'inlet restrictor' to 'intake restrictor' terminology. · T2 BMW M2 CS Cup 2020- permitted to remove door glass and mechanism. · 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. · 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. · 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
  • P1 Move 2000cc and 2300cc engine options to individual spec lines #31012cars addedaddedP1 creates separate spec lines H and I for 2000cc and 2300cc engines at 1400 and 1445 lbs minimum weight respectively.
  • P1 E&O Spec Line B notes #31095wordingwordingP1 Staudacher may run 950 lbs minimum weight with 38.5mm flat plate intake restrictor, removing prior weight-linked restrictor rule.
  • T2 BMW M2 CS Power Stick Part Number #31087wordingwordingT2 BMW M2 CS Cup 2020- mandatory power stick part number assigned as #8324089.
  • P1 Add 1355cc spec line #30890cars addedaddedP1 adds 1355cc motorcycle-based engine line C at 1075 lbs minimum weight, no restrictor required.
  • T2 997.1 EO #30933cars addedaddedT2 Porsche 911/997.1 (06–08) now permits Cargraphics CARP97DFIFKR alternate exhaust manifold.
  • T2 Request #30406wordingunclearT2 BMW M2 CS Cup 2020- weight increases from 3625 to 3600 lbs; Purple power stick mandatory, hot country package allowed.
  • T2 Civic Type R Brake Rotors #29817weightslower · weightT3 Honda Civic Type-R 2020+ allowed brake rotor #45251-TGH-A01 with 25 lb penalty.
  • T2 Mustang S550 Parity in T2 #29925inductionfaster · inductionT2 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 lbsslower · weightT2 BMW Z4M 06–08 minimum weight increases 50 lbs, to 3150.
  • T2 E92 #30639weight -50 lbsfaster · weightT2 BMW E92M3 weight drops 50 lbs to 3425; intake restrictor shrinks from 80mm to 77mm.
  • P1 E&O tonneau cover provision in cockpit opening section #30458wordingwordingP1 cockpit opening section allows tonneau covers to meet minimum dimensions; wording clarified on equipment attachment.
  • P1 Update Spec Line B Notes #30498wordingwordingP1 Staudacher 1005cc homologated before 1-1-2014 may run 38.5mm flat plate intake restrictor at 950 lbs minimum weight.
  • P1 Update Spec Lines C and G notes #30499wordingwordingP1 Spec Line C: FPIR not required at 1150 lbs, 1355cc max may run without FPIR at 1075 lbs. Spec Line G: up to 2000cc runs 30mm SIR at 1400 lbs, 2300cc runs 30mm SIR at 1445 lbs.
  • P1 E&O Maximum Valves Per Cylinder #30559engineengineP1 classes B, C, D maximum valves per cylinder set to 4, previously unspecified.
  • 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 lbsfaster · weightT2 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.
  • P1 Clean up Spec Line A notes section #30424wordingwordingP1 Spec Line A clarifies carburetor induction only, one per cylinder, balance tubes not allowed.
  • P1 Clean up Spec Line H notes section #30425wordingwordingP1 Spec Line H notes clarify peripheral port or bridgeport allowed; wording only.
  • 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 & brakesfaster · suspension & 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.
  • P1 DP02 Sealed 2ltr Engine Option #30038engineremoved · engineP1 Elan DP02-spec Mazda MZR sealed engine option removed effective 3/1/2021.
  • P1 E&O restrictor terminology #30285wordingwordingP1 Engine Table Spec Lines C and G change 'inlet restrictor' to 'intake restrictor' terminology.
  • T2 Request BMW M2CS door glass removal #30254cars addedaddedT2 BMW M2 CS Cup 2020- permitted to remove door glass and mechanism.
  • 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 #29942inductionadded · inductionT2 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 lbsfaster · weightT2 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 & wheelsfaster · tyres & 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.
  • 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.
  • T2 Request to Reevaluate T2 Spec Line for E92 M3 #28266weight -50 lbsfaster · weightT2 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 lbsfaster · inductionT2 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 20202020-10-022:01.101James French · fastest of 18 · top 5 within 1.1s2:01.870James French · fastest of 17 · top 5 within 1.8s159.7David Locke2:24.195Alan Kossof · fastest of 15 · top 5 within 2.5s2:26.803Kurt Rezzetano · fastest of 14 · top 5 within 2.2s147.3Mark Boden+24.933squal +23.094s120.5%qual 119.1%2:12.806Scott Rettich · fastest of 25 · top 5 within 0.6s2:13.271Owen McAllister · fastest of 23 · top 5 within 0.7s143.4Owen McAllister+11.401squal +11.705s109.4%qual 109.7%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+41.878squal +41.108s134.4%qual 133.9%
38 rule changes (P1: 4, T2: 30, FE2: 2, SM: 2)8 weight · 7 cars added · 7 suspension & brakes · 1 aero · 1 engine · 1 induction · 1 removed · 1 tyres & wheels · 7 wording · 4 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. · FE2 oil cooler rule clarified: Setrab 50-625-7612 or any cooler with max core 13 inches wide by 6.5 inches high allowed. · T2 stock replacement brake rotors now allow 2-piece ferrous disks with aluminum hats, within 5% of OE diameter. · 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. · 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. · 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. · P1 intake manifolds unrestricted unless engine requires flat plate restrictor; no plenums or balance pipes on restricted individual runner manifolds. · 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. · 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. · T2 Porsche 911/997 (06-08), 997.2 (09-12), Carrera S (06-08): spoiler, bumper, airdams, rear wing height rules removed. · P1 sealed 2.0L Elan DP02-spec Mazda option removal date extended from 1/1/2020 to 1/1/2021. · 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. · P1 sealed 2.0 MZR engine removed effective 1/1/2020; competitors may run it under Spec Line G. · P1 Spec Line F: Restricted 2.0L Group becomes CN-spec Honda K20A-FD2, 2000cc, 1400 lbs minimum. · 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. · FE minimum weight rises to 1270 lbs; FE2 minimum weight rises to 1270 lbs; new spring options added; tire warmers prohibited.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 & brakesadded · suspension & 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.
  • FE2 FE/FE2 Oil Cooler #29293wordingwordingFE2 oil cooler rule clarified: Setrab 50-625-7612 or any cooler with max core 13 inches wide by 6.5 inches high allowed.
  • 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 lbs
  • 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.
  • 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 & brakesfaster · suspension & 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.
  • 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 & brakesadded · suspension & brakesT1 and T2 Corvettes now allow coilover suspension with 800 lb max coil springs; T1 Z06 conversion no longer T1-only.
  • P1 E&O minimum weights and intake manifolds #28731inductioninductionP1 intake manifolds unrestricted unless engine requires flat plate restrictor; no plenums or balance pipes on restricted individual runner manifolds.
  • T2 Please Add the Following BBK to Allowed List for E92 M3 #28421suspension & brakesadded · suspension & 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 lbsfaster · weightT2 Corvette C5 Z06 weight drops 50 lbs to 3175 with 45mm restrictor, 50 lbs to 3350 with 55mm.
  • T2 Z3M Roadster Weight #28437weightfaster · weightT3 BMW Z3 M & Coupe 98-99 minimum weight reduced to 3150 lbs.
  • T2 Limit Changes to the 997.2 Porsche #28242aeroslower · aeroT2 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.
  • 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.
  • P1 Extend date for removing sealed DP02-spec 2.0L option #28046wordingunclearP1 sealed 2.0L Elan DP02-spec Mazda option removal date extended from 1/1/2020 to 1/1/2021.
  • T2 Please Switch the Solstice GXP as Specified in T2, to T3 #27413cars added -50 lbsfaster · cars 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 & brakesslower · suspension & brakesT2 Nissan 370Z gains StopTech brake kit allowance with 50 lb penalty.
  • T2 2015- Current Ecoboost Mustang #27971weight -100 lbsfaster · weightT2 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 & wheelsfaster · tyres & 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.
  • P1 Remove sealed DP02-spec 2.0 MZR spec #26753removedremovedP1 sealed 2.0 MZR engine removed effective 1/1/2020; competitors may run it under Spec Line G.
  • P1 Update Revised Spec Line F #27745engineengineP1 Spec Line F: Restricted 2.0L Group becomes CN-spec Honda K20A-FD2, 2000cc, 1400 lbs minimum.
  • 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 lbsfaster · weightT2 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 lbsfaster · weightT2 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.
  • FE2 FE / FE2 Update Rules #27624weightslower · weightFE minimum weight rises to 1270 lbs; FE2 minimum weight rises to 1270 lbs; new spring options added; tire warmers prohibited.
Virginia International Raceway Runoffs 20192019-10-051:42.674Todd Slusher · fastest of 14 · top 5 within 1.5s1:43.498Todd Slusher · fastest of 13 · top 5 within 1.0s155.9Jim Devenport1:57.537Cooper I MacNeil · fastest of 19 · top 5 within 3.4s1:58.551Cooper I MacNeil · fastest of 18 · top 5 within 2.4s149.4James Leithauser+15.053squal +14.863s114.5%qual 114.5%1:51.062Liam Snyder · fastest of 20 · top 5 within 1.3s1:52.154Liam Snyder · fastest of 19 · top 5 within 0.7s142.6Robert Vanman+8.656squal +8.388s108.4%qual 108.2%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+32.961squal +31.878s131.8%qual 131.0%
41 rule changes (P1: 14, T2: 23, SM: 4)7 cars added · 7 suspension & brakes · 2 weight · 1 aero · 1 engine · 1 induction · 1 tyres & wheels · 18 wording · 3 other · T2, T3, T4 spare tire and cover removal wording clarified; removable covers now explicitly allowable to remove. · P1 traction control prohibited. · P1 permits mechanical, solenoid, and air-shifters; prohibits electronic pre-selection and multi-wheel power. · P1 minimum bodywork height rule moved and restated with new 115cm aerodynamic part height limit. · P1 consolidates fender louver rules into one section; removes duplicate allowance for louvers and clarifies brake and engine air ducts are permitted. · 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. · P1 anti-intrusion panels now allowed anywhere on chassis sides instead of specified locations. · P1 bodywork wording clarified: comfort and safety for driver and passenger or driver only. · 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. · P1 Engine Table reference cleaned up; no performance change. · P1 Mazda Renesis Rotary engine spec line removed from Engine Table. · P1 Staudacher and Honda K20A-FD2 engine table wording clarified; no performance change. · T2 Mustang GT rear anti-roll bar may now be removed or disconnected. · P1 closed cockpit single-seat cars remain prohibited; rule moved from subsection J.5 to B.4. · 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. · 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. · P1 engine table reference corrected from 'above' to 'below'; ETC/FBW/DBW throttle wording clarified on sensor and fail-safe requirements. · 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. · P1 removes TIR inlet restrictor option; deletes requirement for single turbo/supercharger unit with single restrictor. · P1 CN-spec Honda K20A-FD2 clarified: stock OEM parts required, no machining allowed. · P1 engine rules correct grammar and remove head designs from specification table. · 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
  • T2 Request spare tire/wheel clarification #27012wordingfasterT2, T3, T4 spare tire and cover removal wording clarified; removable covers now explicitly allowable to remove.
  • P1 E&O Transmissions #27098wordingwordingP1 traction control prohibited.
  • P1 E&O Transmissions #27005otheraddedP1 permits mechanical, solenoid, and air-shifters; prohibits electronic pre-selection and multi-wheel power.
  • P1 Move minimum height provision to #27031wordingwordingP1 minimum bodywork height rule moved and restated with new 115cm aerodynamic part height limit.
  • P1 Remove duplicative fender louver provision #27033wordingwordingP1 consolidates fender louver rules into one section; removes duplicate allowance for louvers and clarifies brake and engine air ducts are permitted.
  • 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 & brakesadded · suspension & 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 #27022inductionslower · inductionT2 Cadillac CTS-V 06-07 requires 57mm flat plate restrictor.
  • T2 Correct T2 Mustang tire size #27024tyres & wheelsslower · tyres & wheelsT2 Ford Mustang GT 5.0L tire width reduced from 315 to 295.
  • P1 Missing word E&O #26919wordingwordingP1 anti-intrusion panels now allowed anywhere on chassis sides instead of specified locations.
  • P1 E&O correction to GCR 9.1.8.C.C. #26927wordingwordingP1 bodywork wording clarified: comfort and safety for driver and passenger or driver only.
  • T2 2018+ Audi TT RS Suspension Allowances #26631suspension & brakesadded · suspension & 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 lbsfaster · weightT2 Honda Civic Type-R 2017+ minimum weight rises 150 lbs to 3050, TIR turbo restrictor enlarges 38mm to 50mm.
  • P1 Clean up reference to engine table #26648wordingwordingP1 Engine Table reference cleaned up; no performance change.
  • P1 Remove redundant spec line #26692cars addedremoved · cars addedP1 Mazda Renesis Rotary engine spec line removed from Engine Table.
  • P1 Clean Up Engine Table Language #26590wordingwordingP1 Staudacher and Honda K20A-FD2 engine table wording clarified; no performance change.
  • T2 Request for Removal of Rear Anti-roll Bar in T2 Mustang GT #26533suspension & brakesfaster · suspension & brakesT2 Mustang GT rear anti-roll bar may now be removed or disconnected.
  • P1 Move single-seat closed cockpit provision to #26376wordingwordingP1 closed cockpit single-seat cars remain prohibited; rule moved from subsection J.5 to B.4.
  • SM Request to allow aftermarket fuel filters. #26370otheraddedSM fuel pump and filter now permitted as Mazda or OEM equivalent part.
  • 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 #26187engineadded · engineT2, T3, T4 now allow any thermostat serving original equipment intent only.
  • T2 Ford Mustang Boss 302 (12-13) - correct weight #26287weight -50 lbsfaster · weightT2 Ford Mustang Boss 302 (12-13) minimum weight drops to 3500 lbs.
  • T2 Request camber correction 005-2013 corvette C6 #26288suspension & brakesremoved · suspension & 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 & brakesadded · suspension & brakesT2 Pontiac Firebird and Chevrolet Camaro SS 98-02 permit spring relocation to shock.
  • T2 Cap 2016 Mazda Miata year at 2018 #26388cars addedremoved · cars 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.
  • P1 Correct errors in GCR section 9.1.8.C.J #26144wordingwordingP1 engine table reference corrected from 'above' to 'below'; ETC/FBW/DBW throttle wording clarified on sensor and fail-safe requirements.
  • 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.
  • P1 Remove redundant inlet restrictor provisions #25877wordingwordingP1 removes TIR inlet restrictor option; deletes requirement for single turbo/supercharger unit with single restrictor.
  • P1 Clarify Honda K20A-FD2 parts requirement #25949wordingwordingP1 CN-spec Honda K20A-FD2 clarified: stock OEM parts required, no machining allowed.
  • P1 Correct GCR section 9.1.8.C.J errors #25966wordingwordingP1 engine rules correct grammar and remove head designs from specification table.
  • 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 #25513aeroadded · aeroT2 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 & brakesadded · suspension & brakesT2–T4 subframe bushings now permitted to be replaced with non-spherical bushings of any material.
Sonoma Raceway Runoffs 20182018-10-101:27.714Todd Slusher · fastest of 19 · top 5 within 2.1s1:28.786Perry Richardson · fastest of 19 · top 5 within 0.9s144.0Johnnie Crean1:45.032John Kachadurian · fastest of 30 · top 5 within 2.4s1:45.999John Kachadurian · fastest of 28 · top 5 within 3.0s106.5John Kachadurian+17.213squal +17.318s119.4%qual 119.7%1:35.040Flinn Lazier · fastest of 9 · top 5 within 1.5s1:35.563Flinn Lazier · fastest of 9 · top 5 within 1.7s126.8Scott Rettich+6.777squal +7.326s107.6%qual 108.4%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+26.492squal +26.641s129.8%qual 130.4%
No rule changes on record between these events
Indianapolis Motor Speedway Runoffs 20172017-09-251:30.794Jim Devenport · fastest of 19 · top 5 within 2.8s1:31.499Jim Devenport · fastest of 16 · top 5 within 2.2s1:48.618John M Buttermore · fastest of 26 · top 5 within 0.8s1:48.769John M Buttermore · fastest of 25 · top 5 within 1.2s+17.270squal +17.824s118.9%qual 119.6%1:58.306Chris Haldeman · fastest of 86 · top 5 within 0.5s1:59.100Michael Gagliardo · fastest of 83 · top 5 within 0.6s+27.601squal +27.512s130.2%qual 130.3%
No rule changes on record between these events
Mid-Ohio Sports Car Course Runoffs 20162016-09-191:17.308James Devenport · fastest of 14 · top 5 within 2.7s1:19.407Gianpaolo Ciancimino · fastest of 13 · top 5 within 1.8s1:31.563Preston Calvert · fastest of 22 · top 5 within 0.5s1:32.691John M Buttermore · fastest of 20 · top 5 within 1.5s+13.284squal +14.255s116.7%qual 118.4%1:40.514Justin Hille · fastest of 45 · top 5 within 0.3s1:40.764Michael Carter · fastest of 44 · top 5 within 0.3s+21.357squal +23.206s126.9%qual 130.0%
No rule changes on record between these events
Daytona International Speedway Runoffs 20152015-09-211:49.219Jim Downing · fastest of 9 · top 5 within 2.2s1:49.792Gianpaolo Ciancimino · fastest of 10 · top 5 within 1.7s2:00.172Kurt Rezzetano · fastest of 20 · top 5 within 3.2s2:01.077Kurt Rezzetano · fastest of 19 · top 5 within 2.8s+11.285squal +10.953s110.3%qual 110.0%2:18.661Andrew Carbonell · fastest of 62 · top 5 within 0.6s2:24.067Todd Lamb · fastest of 59 · top 5 within 0.8s+34.275squal +29.442s131.2%qual 127.0%

By track

TrackEventsTypical % of P1BestLatest
Road America4100.0%2 of 4 with P1100.0%Runoffs 2020100.0%Runoffs 2024
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 P1's best on the same day: the weather, the track and its configuration cancel out, so one figure compares across tracks and years where lap times cannot. 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.