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BoP Lab / Classes / STU

STU vs F5 vs SM vs T4 pace at every track

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

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

Closest to the field: STU 100.0% of STU Eric Heinrich, Daytona International Speedway Runoffs 2015 race · F5 93.1% of STU Sven de Vries, Virginia International Raceway Runoffs 2022 race · SM 91.3% of STU Travis Wiley, Virginia International Raceway Runoffs 2022 race · T4 95.5% of STU John Heinricy, Virginia International Raceway Runoffs 2022 race

1:402:002:202:4042 rule changes between Runoffs 2018 and Runoffs 201942 ▾50 rule changes between Runoffs 2019 and Runoffs 202050 ▾36 rule changes between Runoffs 2020 and Runoffs 202136 ▾57 rule changes between Runoffs 2021 and Runoffs 202257 ▾24 rule changes between Runoffs 2022 and Runoffs 202324 ▾36 rule changes between Runoffs 2023 and Runoffs 202436 ▾51 rule changes between Runoffs 2024 and Runoffs 202551 ▾43 rule changes between Runoffs 2025 and Runoffs 202643 ▾STU race best at Runoffs 2015: 2:06.756 (Eric Heinrich)STU race best at Runoffs 2016: 1:34.597 (Cameron Maugeri)STU race best at Runoffs 2017: 1:49.387 (Rob Huffmaster)STU race best at Runoffs 2018: 1:46.514 (Kevin Boehm)STU race best at Runoffs 2019: 2:00.483 (Kevin Boehm)STU race best at Runoffs 2020: 2:28.410 (Anthony Geraci)STU race best at Runoffs 2021: 1:47.441 (Joe Moser)STU race best at Runoffs 2022: 2:32.357 (Mark Liller)STU race best at Runoffs 2023: 2:02.302 (Mark Liller)STU race best at Runoffs 2024: 2:25.824 (Thomas Noble)STU race best at Runoffs 2025: 2:24.497 (Chip Herr)STU race best at Runoffs 2026: 2:26.416 (Richard Astacio)STU qualifying best at Runoffs 2015: 2:05.494 (Eric Heinrich)STU qualifying best at Runoffs 2016: 1:32.738 (Joe Moser)STU qualifying best at Runoffs 2017: 1:48.921 (Rob Huffmaster)Off the chart: STU qualifying best at Runoffs 2018: 1:19.234 (Franklin Church)STU qualifying best at Runoffs 2019: 1:59.948 (Kevin Boehm)STU qualifying best at Runoffs 2020: 2:27.883 (David Fiorelli)STU qualifying best at Runoffs 2021: 1:47.078 (Joe Moser)STU qualifying best at Runoffs 2022: 2:00.615 (Johan Schwartz)STU qualifying best at Runoffs 2023: 2:00.389 (Johan Schwartz)STU qualifying best at Runoffs 2024: 2:26.227 (Thomas Noble)STU qualifying best at Runoffs 2025: 2:23.083 (Peter Cunningham)STU qualifying best at Runoffs 2026: 2:24.912 (Richard Astacio)F5 race best at Runoffs 2015: 2:03.298 (Matthew Strand)F5 race best at Runoffs 2016: 1:29.853 (Steven Thompson)F5 race best at Runoffs 2017: 1:42.860 (Wiley Clinton McMahan)F5 race best at Runoffs 2018: 1:42.491 (David Lapham)F5 race best at Runoffs 2019: 1:57.572 (Wiley Mcmahan)F5 race best at Runoffs 2020: 2:21.391 (James Weida)F5 race best at Runoffs 2021: 1:43.140 (Sven de Vries)F5 race best at Runoffs 2022: 2:21.862 (Sven de Vries)F5 qualifying best at Runoffs 2015: 2:01.824 (W. Clint McMahan)F5 qualifying best at Runoffs 2016: 1:28.528 (Calvin Stewart)F5 qualifying best at Runoffs 2017: 1:43.136 (Wiley Clinton McMahan)F5 qualifying best at Runoffs 2018: 1:41.807 (Jeff Jorgenson)F5 qualifying best at Runoffs 2019: 1:57.361 (Wiley Mcmahan)F5 qualifying best at Runoffs 2020: 2:20.954 (Calvin Stewart)F5 qualifying best at Runoffs 2021: 1:42.619 (Ryan Mayfield)F5 qualifying best at Runoffs 2022: 1:57.689 (James Weida)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)T4 race best at Runoffs 2015: 2:15.994 (Philip Royle)T4 race best at Runoffs 2016: 1:40.397 (Oscar Jackson)T4 race best at Runoffs 2017: 1:56.923 (Oscar Jackson)T4 race best at Runoffs 2018: 1:54.030 (John Heinricy)T4 race best at Runoffs 2019: 2:10.959 (Nick Leverone)T4 race best at Runoffs 2020: 2:37.881 (Chi Ho)T4 race best at Runoffs 2021: 1:55.929 (John Heinricy)T4 race best at Runoffs 2022: 2:25.443 (John Heinricy)T4 race best at Runoffs 2023: 2:11.962 (Devin Anderson)T4 race best at Runoffs 2024: 2:34.208 (Alex Lozano)T4 race best at Runoffs 2025: 2:32.633 (Alex Lozano)T4 race best at Runoffs 2026: 2:35.757 (Matt Spicuzzi)T4 qualifying best at Runoffs 2015: 2:15.886 (Philip Royle)T4 qualifying best at Runoffs 2016: 1:38.813 (Jonathan Yanca)T4 qualifying best at Runoffs 2017: 1:56.566 (Oscar Jackson)T4 qualifying best at Runoffs 2018: 1:52.339 (Gresham Wagner)T4 qualifying best at Runoffs 2019: 2:11.257 (John Heinricy)T4 qualifying best at Runoffs 2020: 2:37.403 (John Heinricy)T4 qualifying best at Runoffs 2021: 1:54.397 (Stephen Blethen)T4 qualifying best at Runoffs 2022: 2:09.577 (John Heinricy)T4 qualifying best at Runoffs 2023: 2:10.514 (Devin Anderson)T4 qualifying best at Runoffs 2024: 2:34.430 (Matt Spicuzzi)T4 qualifying best at Runoffs 2025: 2:32.956 (Matt Spicuzzi)T4 qualifying best at Runoffs 2026: 2:35.876 (Matt Spicuzzi)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
STUF5SMT4solid race · dashed qualifying · slower is lower
95%100%105%110%115%42 rule changes between Runoffs 2018 and Runoffs 201942 ▾50 rule changes between Runoffs 2019 and Runoffs 202050 ▾36 rule changes between Runoffs 2020 and Runoffs 202136 ▾57 rule changes between Runoffs 2021 and Runoffs 202257 ▾24 rule changes between Runoffs 2022 and Runoffs 202324 ▾36 rule changes between Runoffs 2023 and Runoffs 202436 ▾51 rule changes between Runoffs 2024 and Runoffs 202551 ▾43 rule changes between Runoffs 2025 and Runoffs 202643 ▾STU race best at Runoffs 2015: 100.0% of STU's (Eric Heinrich)STU race best at Runoffs 2016: 100.0% of STU's (Cameron Maugeri)STU race best at Runoffs 2017: 100.0% of STU's (Rob Huffmaster)STU race best at Runoffs 2018: 100.0% of STU's (Kevin Boehm)STU race best at Runoffs 2019: 100.0% of STU's (Kevin Boehm)STU race best at Runoffs 2020: 100.0% of STU's (Anthony Geraci)STU race best at Runoffs 2021: 100.0% of STU's (Joe Moser)STU race best at Runoffs 2022: 100.0% of STU's (Mark Liller)STU race best at Runoffs 2023: 100.0% of STU's (Mark Liller)STU race best at Runoffs 2024: 100.0% of STU's (Thomas Noble)STU race best at Runoffs 2025: 100.0% of STU's (Chip Herr)STU race best at Runoffs 2026: 100.0% of STU's (Richard Astacio)STU qualifying best at Runoffs 2015: 100.0% of STU's (Eric Heinrich)STU qualifying best at Runoffs 2016: 100.0% of STU's (Joe Moser)STU qualifying best at Runoffs 2017: 100.0% of STU's (Rob Huffmaster)STU qualifying best at Runoffs 2018: 100.0% of STU's (Franklin Church)STU qualifying best at Runoffs 2019: 100.0% of STU's (Kevin Boehm)STU qualifying best at Runoffs 2020: 100.0% of STU's (David Fiorelli)STU qualifying best at Runoffs 2021: 100.0% of STU's (Joe Moser)STU qualifying best at Runoffs 2022: 100.0% of STU's (Johan Schwartz)STU qualifying best at Runoffs 2023: 100.0% of STU's (Johan Schwartz)STU qualifying best at Runoffs 2024: 100.0% of STU's (Thomas Noble)STU qualifying best at Runoffs 2025: 100.0% of STU's (Peter Cunningham)STU qualifying best at Runoffs 2026: 100.0% of STU's (Richard Astacio)F5 race best at Runoffs 2015: 97.3% of STU's (Matthew Strand)F5 race best at Runoffs 2016: 95.0% of STU's (Steven Thompson)F5 race best at Runoffs 2017: 94.0% of STU's (Wiley Clinton McMahan)F5 race best at Runoffs 2018: 96.2% of STU's (David Lapham)F5 race best at Runoffs 2019: 97.6% of STU's (Wiley Mcmahan)F5 race best at Runoffs 2020: 95.3% of STU's (James Weida)F5 race best at Runoffs 2021: 96.0% of STU's (Sven de Vries)F5 race best at Runoffs 2022: 93.1% of STU's (Sven de Vries)F5 qualifying best at Runoffs 2015: 97.1% of STU's (W. Clint McMahan)F5 qualifying best at Runoffs 2016: 95.5% of STU's (Calvin Stewart)F5 qualifying best at Runoffs 2017: 94.7% of STU's (Wiley Clinton McMahan)Off the chart: F5 qualifying best at Runoffs 2018: 128.5% of STU's (Jeff Jorgenson)F5 qualifying best at Runoffs 2019: 97.8% of STU's (Wiley Mcmahan)F5 qualifying best at Runoffs 2020: 95.3% of STU's (Calvin Stewart)F5 qualifying best at Runoffs 2021: 95.8% of STU's (Ryan Mayfield)F5 qualifying best at Runoffs 2022: 97.6% of STU's (James Weida)SM race best at Runoffs 2015: 113.7% of STU's (Todd Lamb)SM race best at Runoffs 2016: 106.5% of STU's (Michael Carter)SM race best at Runoffs 2017: 108.9% of STU's (Michael Gagliardo)SM race best at Runoffs 2018: 108.2% of STU's (Michael Carter)SM race best at Runoffs 2019: 113.3% of STU's (Elivan Goulart)SM race best at Runoffs 2020: 110.3% of STU's (Preston Pardus)SM race best at Runoffs 2021: 110.6% of STU's (Brian Henderson)Off the chart: SM race best at Runoffs 2022: 91.3% of STU's (Travis Wiley)SM race best at Runoffs 2023: 111.4% of STU's (Julian DaCosta)SM race best at Runoffs 2024: 110.7% of STU's (Brett Kowalski)SM race best at Runoffs 2025: 113.8% of STU's (Kyle Greenhill)SM race best at Runoffs 2026: 111.1% of STU's (Francisco Barroso)SM qualifying best at Runoffs 2015: 110.5% of STU's (Andrew Carbonell)SM qualifying best at Runoffs 2016: 108.4% of STU's (Justin Hille)SM qualifying best at Runoffs 2017: 108.6% of STU's (Chris Haldeman)Off the chart: SM qualifying best at Runoffs 2018: 144.3% of STU's (Ken Sutherland)SM qualifying best at Runoffs 2019: 112.2% of STU's (Todd Buras)SM qualifying best at Runoffs 2020: 109.7% of STU's (Kyle Greenhill)SM qualifying best at Runoffs 2021: 109.9% of STU's (Brian Henderson)SM qualifying best at Runoffs 2022: 111.6% of STU's (Danny Steyn)SM qualifying best at Runoffs 2023: 112.1% of STU's (Danny Steyn)SM qualifying best at Runoffs 2024: 110.2% of STU's (Ethan Goulart)SM qualifying best at Runoffs 2025: 114.0% of STU's (Bobby Gossett)SM qualifying best at Runoffs 2026: 111.9% of STU's (Brett Kowalski)T4 race best at Runoffs 2015: 107.3% of STU's (Philip Royle)T4 race best at Runoffs 2016: 106.1% of STU's (Oscar Jackson)T4 race best at Runoffs 2017: 106.9% of STU's (Oscar Jackson)T4 race best at Runoffs 2018: 107.1% of STU's (John Heinricy)T4 race best at Runoffs 2019: 108.7% of STU's (Nick Leverone)T4 race best at Runoffs 2020: 106.4% of STU's (Chi Ho)T4 race best at Runoffs 2021: 107.9% of STU's (John Heinricy)T4 race best at Runoffs 2022: 95.5% of STU's (John Heinricy)T4 race best at Runoffs 2023: 107.9% of STU's (Devin Anderson)T4 race best at Runoffs 2024: 105.7% of STU's (Alex Lozano)T4 race best at Runoffs 2025: 105.6% of STU's (Alex Lozano)T4 race best at Runoffs 2026: 106.4% of STU's (Matt Spicuzzi)T4 qualifying best at Runoffs 2015: 108.3% of STU's (Philip Royle)T4 qualifying best at Runoffs 2016: 106.6% of STU's (Jonathan Yanca)T4 qualifying best at Runoffs 2017: 107.0% of STU's (Oscar Jackson)Off the chart: T4 qualifying best at Runoffs 2018: 141.8% of STU's (Gresham Wagner)T4 qualifying best at Runoffs 2019: 109.4% of STU's (John Heinricy)T4 qualifying best at Runoffs 2020: 106.4% of STU's (John Heinricy)T4 qualifying best at Runoffs 2021: 106.8% of STU's (Stephen Blethen)T4 qualifying best at Runoffs 2022: 107.4% of STU's (John Heinricy)T4 qualifying best at Runoffs 2023: 108.4% of STU's (Devin Anderson)T4 qualifying best at Runoffs 2024: 105.6% of STU's (Matt Spicuzzi)T4 qualifying best at Runoffs 2025: 106.9% of STU's (Matt Spicuzzi)T4 qualifying best at Runoffs 2026: 107.6% of STU's (Matt Spicuzzi)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
STUF5SMT4solid race · dashed qualifying · each class's best lap as a share of STU's at the same event (the reference class, changeable above); 100% is level, less is quicker, so up the chart is quicker
EventSTUF5SMT4
Qual best Race best Trap Qual best Race best Trap vs STU % of STU Qual best Race best Trap vs STU % of STU Qual best Race best Trap vs STU % of STU 
Road America Runoffs 20262026-09-282:24.912Richard Astacio · fastest of 17 · top 5 within 2.6s+1.829s (+1.28%)2:26.416Richard Astacio · fastest of 16 · top 5 within 1.5s+1.919s (+1.33%)145.1Hugh Stewart+0.8 mph (+0.5%)2:42.173Brett Kowalski · fastest of 34 · top 5 within 0.3s-0.938s (-0.58%)2:42.725Francisco Barroso · fastest of 35 · top 5 within 0.2s-1.705s (-1.04%)119.6Wyatt Couch+0.3 mph (+0.3%)+16.309squal +17.261s111.1%qual 111.9%2:35.876Matt Spicuzzi · fastest of 12 · top 5 within 2.4s+2.920s (+1.91%)2:35.757Matt Spicuzzi · fastest of 12 · top 5 within 2.7s+3.124s (+2.05%)127.6Matt Spicuzzi-6.0 mph (-4.5%)+9.341squal +10.964s106.4%qual 107.6%
43 rule changes (STU: 15, SM: 2, T4: 26)12 weight · 7 induction · 5 cars added · 5 suspension & brakes · 5 tyres & wheels · 1 engine · 1 removed · 1 wording · 6 othershowhide
  • STU Wheel and tire requirements for GT3U #40679tyres & wheels
  • T4 02-06 R53 Mini Cooper Hotchkins Rear Camber Arms #40677suspension & brakes
  • T4 Is it time? #40653cars added
  • T4 Combine T4 BRZ/86/FRS generations #40656weight
  • SM Rear Toe Link #40271other
  • STU 9” Wheels #40433tyres & wheels
  • STU Weight adjustment to former GT3U cars #40474weight
  • T4 Dodge Neon DOHC Weight #40329weight
  • STU Request to allow BMW M50B20TU engine in STU #40202engine
  • STU Calculating Weight #40224weight
  • T4 SPB In T4 #39973other
  • T4 02-06 Mini Cooper S #40106weight -50 lbs
  • T4 02-06 Mini Cooper S Fuel #40107other
  • T4 Shock error #40176suspension & brakes
  • T4 Max Tire Sizes #40183tyres & wheels
  • STU Turbo Restrictor Size Increase Request #40008induction
  • STU GT86 Cups Car in STU #40028weight
  • T4 2003 Honda Civic Si Classification #39999cars added
  • SM Part Number Change Request #39914wording
  • STU Mazda Rx-8 Renesis - Streetported Variant & Added Weight #39785weight
  • STU Eliminate 33 and 34 mm TIRs #39872weight
  • T4 16-24 ND MX5 T4 #39934suspension & brakes
  • STU Fab 9 Racing Intake Manifold in STU #39767induction
  • T4 ND MX-5 Spec Line Rewrite Request #39802weight -100 lbs
  • T4 4.0 Mustang spec line cleanup #39831induction
  • T4 T4 and T3 Feedback #39230removed
  • T4 T4 Mustang 4.0 #39489induction
  • T4 Allow Alt Bushing Material in Toe Links #39607suspension & brakes
  • STU Request for Permission on Aftermarket Turbo Kit and Intake #39529induction
  • T4 Alternate Placement of Fuse Panel and Electronics Request #39370other
  • T4 Clarify T4 Brake Rotor Allowance #39503suspension & brakes
  • STU Turbo Inlet Restrictor Table #38961induction
  • STU 275 Tire Rule #38983tyres & wheels
  • STU STU Honda Engine weight penalty #39375weight
  • T4 Classing 1995-99 Dodge Neon SOHC #39285cars added
  • STU Non-Homologated Engine Swaps - Specifically K24A2 w/ Honda CRZ #38746weight
  • T4 02-06 Mini Cooper Gear Ratios #38966other
  • T4 Reinstatement of the 2005-2010 Cobalt into T4 #38987cars added
  • T4 Request to Classify Mercedes C230K #39080cars added
  • T4 ND Gearset Request for T4 #39166other
  • T4 E&O wheel size on ND #39168tyres & wheels
  • T4 ND Spec Lines Wrong PT#'s #39170weight
  • T4 Touring 4 Post-Runoffs BOP Adjustments and Changes #39251induction -100 lbs
Road America Runoffs 20252025-09-292:23.083Peter Cunningham · fastest of 16 · top 5 within 2.6s-3.144s (-2.15%)2:24.497Chip Herr · fastest of 15 · top 5 within 3.8s-1.327s (-0.91%)144.3Chip Herr-1.0 mph (-0.7%)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%)+19.933squal +20.028s113.8%qual 114.0%2:32.956Matt Spicuzzi · fastest of 10 · top 5 within 3.8s-1.474s (-0.95%)2:32.633Alex Lozano · fastest of 10 · top 5 within 4.3s-1.575s (-1.02%)133.7Alex Lozano+4.4 mph (+3.4%)+8.136squal +9.873s105.6%qual 106.9%
51 rule changes (STU: 18, SM: 4, T4: 29)13 weight · 8 tyres & wheels · 6 cars added · 5 engine · 2 induction · 2 suspension & brakes · 1 aero · 4 wording · 10 othershowhide
  • STU Lotus Weight Reduction E&O #38919weight
  • STU STU-TCR Adjustments #38723weight
  • STU Lotus Weight Reduction #38772weight -50 lbs
  • T4 Incorrect Touring Heading #38451wording
  • STU 2.8-3.2L N/A Engine Allowances #38007engine
  • STU 2006-2015 Mazda Miata Intake Manifold #38422induction
  • STU Requesting Approval of the JDM Honda h23a #38489cars added
  • T4 Allow B-Spec cars to run in T4 #38439other
  • SM SMX Data Submission - Penalties #38248other
  • SM SMX Penaly Clarification updated language #38337wording
  • T4 T4 Mustang #38059weight -100 lbs
  • T4 SSC tire allowance #38216tyres & wheels
  • SM Clarify Tire Marking Regs #38005tyres & wheels
  • STU Wheel Size Inconsistency #38018tyres & wheels
  • STU Table C: STU-GT3U Clarification #38268weight
  • T4 Correct Ring and Pinion Ratio to T3, Sorry I Mean T4 3.7 V6 Stang #38041wording
  • T4 T4 Mustang #38058aero
  • STU BMW N54/N55 Engine Allowance Follow Up #37447engine
  • STU STU Mini Cooper pulley size clarification re: letter #36980 #37717wording
  • STU Question About a Weight Modifier #37782weight
  • STU Increase Minimum Weight #37919weight +100 lbs
  • T4 Ford Mustang V6 (05-14) #37516other
  • T4 Request to Classify Club Spec in Appropriate Touring Classes #37523cars added
  • STU Audi 1.8t Wagon STU Table B #36685weight
  • STU Merger GT3 to STU #37486other
  • STU GT3 TCR Tire allowance #37494tyres & wheels
  • T4 Remove spec lines that have expired #37269induction
  • T4 2016-2018 Mazda Miata MX5 #37085weight -75 lbs
  • SM E&O SMX Regs 9.1.7.1.D.5.u-.w #37070other
  • STU Request to Remove Miata Hubs from General category #37138tyres & wheels
  • STU BMW N54/N55 Engine Allowance #37146engine
  • T4 Redundant Verbiage Regarding Mustang Spec Lines for Driveshaft #36484suspension & brakes
  • T4 R53 Mini Cooper S Weight Reduction Request #36612weight
  • T4 Allowable Wheel Offset #36855tyres & wheels
  • T4 Fuel Emissions Components #37076engine
  • T4 2019-2024 Mazda 3 for T4 #37077cars added
  • T4 fix brake wording #37129suspension & brakes
  • T4 Evaporative emissions systems #37130engine
  • T4 Allow Spec MX5 upgrade kit for 2009-11 RX8 S2 Transmision #37140other
  • T4 Move Spec Boxster to T4 #37158cars added
  • T4 3.7 Mustangs to T4 #37188cars added
  • T4 BMW 320i Spec Line #37204other
  • T4 MX5 2006-2015 NC Help #37221other
  • T4 Classification for a 2005 Cadillac CTS 3.6 liter 6 speed manual #37224cars added
  • T4 Civic SI in T4 #37248weight -50 lbs
  • T4 2006-2015 T4 NC Mx5 spec line #37278weight
  • T4 ND MX-5 wheel allowance #37279tyres & wheels
  • T4 T4 BOP #37281weight +75 lbs
  • T4 Allow 7.5 #37286tyres & wheels
  • STU R53 15% Pulley Request #36980other
  • T4 Bop Request 06-11 Honda Civic Si #37013other
Road America Runoffs 20242024-10-012:26.227Thomas Noble · fastest of 18 · top 5 within 2.3s-1.656s (-1.12%)2:25.824Thomas Noble · fastest of 17 · top 5 within 2.4s-2.586s (-1.74%)145.3Thomas Noble+1.1 mph (+0.8%)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%)+15.662squal +14.879s110.7%qual 110.2%2:34.430Matt Spicuzzi · fastest of 15 · top 5 within 1.8s-2.973s (-1.89%)2:34.208Alex Lozano · fastest of 14 · top 5 within 2.2s-3.673s (-2.33%)129.3Alex Lozano-0.9 mph (-0.7%)+8.384squal +8.203s105.7%qual 105.6%
36 rule changes (STU: 4, SM: 4, T4: 28)10 weight · 6 suspension & brakes · 4 induction · 2 aero · 2 cars added · 2 engine · 1 removed · 1 wording · 8 othershowhide
  • SM SMX Camera Rule Correction #36496wording
  • SM AIM ECU Protocol #36556engine
  • SM OE versus OEM Definitons #36608other
  • SM Shifter Bushing #36611suspension & brakes
  • STU RWD Turbo Disadvantage #36255induction
  • T4 T4 Camaro V6 weight reduction #36232weight
  • T4 BOP adjustment for ND MX5s #36345weight -50 lbs
  • T4 Mustang T2/T3 #35877other
  • T4 Homologation of car to T4 #36030cars added
  • T4 T2-T4 Driveshaft Mistake...? #36050weight
  • T4 MINI Cooper S Spec Lines Corrections. #36086removed
  • T4 Allow Removal of Sound Tubes #36130induction
  • T4 B8/8.5 Audi S4 T3 and T2 #36195cars added
  • T4 Allow OEM Front Spoiler 06-08 Miata in T4 #35941aero
  • T4 T4 Mustang Weight Reduction In T4 Spec #36051weight -50 lbs
  • T4 R53 Mini Cooper S spec line request In #36056suspension & brakes
  • T4 Allow T4 and T3 RX8 to Disable/Remove Factory Oil Inj. #35761engine
  • T4 2023 ND2 Miata Classification and Allowances #35837weight
  • T4 Errors and Omissions for 06-09 VW Rabbit Rotor #35851suspension & brakes
  • T4 Driveshafts #35916weight
  • T4 GCR ERROR - letter not properly applied to GCR #35999weight
  • T4 Corrections to T4 RX8 Spec line #35767aero
  • STU Letter #35397 addendum #35453weight
  • STU S54 Drysump #35464other
  • T4 Reorganize Spec Lines #35375induction
  • T4 Allow any 400lb rear spring in the RX8 #35433suspension & brakes
  • T4 370Z Brake Rotor Size Correction #35487suspension & brakes
  • STU ST Electric-Assisted Steering Systems #35066other
  • T4 More Car Lightening Stuff #35319weight
  • T4 ND Missed Items #35352other
  • T4 Inclusion of B-C spec cars in T4 #35374other
  • T4 T2-T4 Set expiration dates on spec lines #35378induction
  • T4 Mazda MX-5 ND1 Spec Line Request #34232weight +50 lbs
  • T4 BRZ/FRS/86 Spring Allowance #35038suspension & brakes
  • T4 TSX Allowance #35219other
  • T4 Requested Update of Model Years of 370Z #35231other
Virginia International Raceway Runoffs 20232023-09-232:00.389Johan Schwartz · fastest of 13 · top 5 within 2.3s-0.226s (-0.19%)2:02.302Mark Liller · fastest of 14 · top 5 within 1.6s-30.055s (-19.73%)144.0Mark Liller+0.1 mph (+0.1%)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%)+13.927squal +14.597s111.4%qual 112.1%2:10.514Devin Anderson · fastest of 24 · top 5 within 0.5s+0.937s (+0.72%)2:11.962Devin Anderson · fastest of 23 · top 5 within 0.1s-13.481s (-9.27%)127.8Raymond Blethen+0.5 mph (+0.4%)+9.660squal +10.125s107.9%qual 108.4%
24 rule changes (STU: 3, SM: 1, T4: 20)8 weight · 4 suspension & brakes · 3 cars added · 2 induction · 1 tyres & wheels · 2 wording · 4 othershowhide
  • T4 Inclusion of similar car. (CLK 320) #34626other
  • T4 Rules Clarification for Mazda RX8 Spec Line #34395weight
  • T4 rule book corrections #34437wording
  • T4 Ride Height Correction for the T3 Solstice. #34615suspension & brakes
  • STU 2022 Toyota GR Cup for STU #34449cars added
  • T4 2002-2006 Mini Cooper S R53 Spec Line Request #34336weight -50 lbs
  • T4 05-06 Mini Wheel Weight #34112weight
  • T4 06-09 VW Rabbit #34153induction
  • T4 96-01 Audi a4 2.8 Spring Rate #34217suspension & brakes
  • STU Alternate OEM Miata Intake Manifold #33827induction
  • T4 Request to Classify 2004-2008 Acura TSX in T4 #33590cars added
  • T4 T4 Mustang Brakes/Swaybar #34036suspension & brakes
  • STU E&O STU NA Weight Chart. #33737weight
  • T4 BMW 320I intercooler #33762other
  • T4 2019-2021 Mazda MX5 ND2 #32027cars added
  • T4 Mustang OEM Grill Request #33333other
  • T4 Mazda OEM LSD was letter 32655 typo #33666wording
  • SM BOP for NB1 and NB2 #32309weight
  • T4 Allowable Springs and Sway Bars for 06-11 Civic si Spec Line #33294suspension & brakes
  • T4 Touring (T2-T5) Category #33617tyres & wheels
  • T4 ENO 9.1.9.2.D.1.e.1.a. #33651other
  • T4 T4 mustang #32789weight -25 lbs
  • T4 Mazda OEM LSD was letter 32655 #32933weight -25 lbs
  • T4 Another 2022 BRZ/86 T3 request #32945weight +225 lbs
Virginia International Raceway Runoffs 20222022-09-242:00.615Johan Schwartz · fastest of 21 · top 5 within 2.6s+0.667s (+0.56%)2:32.357Mark Liller · fastest of 19 · top 5 within 4.3s+31.874s (+26.46%)143.9Johan Schwartz+0.1 mph (+0.1%)1:57.689James Weida · fastest of 11 · top 5 within 3.9s+0.328s (+0.28%)2:21.862Sven de Vries · fastest of 10 · top 5 within 14.3s+24.290s (+20.66%)142.9Calvin Stewart+0.1 mph (+0.1%)-10.495squal -2.926s93.1%qual 97.6%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%)-13.250squal +14.049s91.3%qual 111.6%2:09.577John Heinricy · fastest of 18 · top 5 within 0.7s-1.680s (-1.28%)2:25.443John Heinricy · fastest of 18 · top 5 within 2.5s+14.484s (+11.06%)127.4Nick Leverone-1.5 mph (-1.2%)-6.914squal +8.962s95.5%qual 107.4%
57 rule changes (STU: 21, F5: 6, SM: 1, T4: 29)12 weight · 9 suspension & brakes · 8 engine · 6 tyres & wheels · 5 induction · 4 cars added · 1 aero · 1 removed · 2 wording · 9 othershowhide
  • F5 Intake Boots Correction #33028induction
  • F5 Ensure availability of ECU for Rotax engines #32695engine
  • STU Request Mazda 13 B turbo #32668induction
  • STU Hood Vents and Intercooler Scoops #32733other
  • STU Non 4 valve weight reduction removed #32808weight
  • T4 04-09 Mazda3 Balance Shaft Delete Kit #32795other
  • F5 Clarify stepped exhaust header references #32743engine
  • STU Error in new minimum weight table when combined with other text #32711weight
  • STU Redundant Language in May GCR #32713engine
  • F5 593 carb boot availability and oil pump clarification #32527induction
  • T4 Request Wider Wheels for Hyundai Tiburon #32536tyres & wheels
  • STU Opposed to the Proposed STU Weight Chart #32381weight
  • STU Clarification request for GCR 9.1.4.D.3.a Splitter Definition #32414aero
  • T4 Request to Add Spec Line for 2004-2009 Mazda3 i 2.0 #32395weight
  • T4 Request Alternate Front & Rear Strut/Shock Top Hats #32452suspension & brakes
  • SM Update GCR Section 9.1.7.3.A.1. #32217suspension & brakes
  • STU Request Adjustment to Min Weight for STU BMW E36 M3 (95-99) #31535weight -90 lbs
  • STU BMW E36 M3 Canadian (North American) S50B32 engine #31866engine
  • STU Engine Swap Origin Country #32209engine
  • STU CRX/Civic Del Sol #32214cars added
  • STU Error correction #32383weight
  • STU Single TB Weight Modifiers Add to Chart #32393weight
  • T4 Request to Allow the Use of Aftermarket ECU's in Touring #31067engine
  • T4 Request JWT BSR Kit for 02-06 Nissan Sentra SE-R/Spec V #31685other
  • T4 Please Confirm Touring 4 (98-00) BMW 323 is E46 generation #31972other
  • T4 RX-8 Spring Part Numbers (E&O) #32151suspension & brakes
  • T4 04-09 Mazda3 Tire Limit Clarification #32249tyres & wheels
  • T4 Shock Part Number Errors & Omissions #32252suspension & brakes
  • T4 Update Solo Spec Coupe to latest '20 specs for Road Racing #32262other
  • T4 Request 2016 Mazda MX5 springs #32265suspension & brakes
  • F5 E&O class name #32194other
  • STU Single TB Weight Modifiers #31449weight
  • STU Request to Remove A4 1.8t from STU Spec Line Tables #31465weight
  • STU Improved Touring Tires #32063tyres & wheels
  • T4 Reply to letter #31486/29879 T2-T4 Grill openings #31935suspension & brakes
  • T4 BRZ vs BRZ TS #32022tyres & wheels
  • STU Request Allowance for Balance Shaft Delete in STU #31434engine
  • STU Request Louvers in hood vents #31916other
  • T4 MX-5 Durability Detailed #31102weight
  • T4 Request Allowances for 2005 - 2010 Mustang #31624wording
  • F5 Data Box Mounting Plate #31638other
  • STU Request to Add Honda K23 Spec Line #30682cars added
  • STU RE: Aug FT letter 30682 #31060other
  • STU Throttling Device Clarification #31323induction
  • T4 Reply to letter 29879 T2-T4 Grill Openings #31486suspension & brakes
  • T4 Please Adjust 98-00 BMW 323 Min Weight to Reflect Current Class #31595weight -200 lbs
  • T4 Consolidate 12-13 and 14-15 Honda Civic Si spec lines for T4 #31596removed
  • T4 Request to clarify radiator hoses #31682wording
  • T4 Clarify Permitted/Allowed #31743suspension & brakes
  • T4 Correct RSX wording #31746tyres & wheels
  • T4 Camaro #31751suspension & brakes
  • T4 Nissan Sentra SE-R Spec. V #30958cars added
  • T4 Mazda RX-8 Spec Line Suspension Parts #31113induction
  • T4 Diverter Valve Plunger Upgrade #31307engine
  • T4 Adjust Honda FWD in T4 to encourage more Drivetrain Diversity #31472tyres & wheels
  • T4 Touring 4 BOP adjustments for 2022 #31482weight -175 lbs
  • T4 Request to Classify 2014 VW Jetta 1.8t TSI #30436cars added
Indianapolis Motor Speedway Runoffs 20212021-09-251:47.078Joe Moser · fastest of 30 · top 5 within 2.0s-1.843s (-1.69%)1:47.441Joe Moser · fastest of 28 · top 5 within 1.8s-1.946s (-1.78%)146.9Kip VanSteenburg1:42.619Ryan Mayfield · fastest of 22 · top 5 within 1.6s-0.517s (-0.50%)1:43.140Sven de Vries · fastest of 20 · top 5 within 1.7s+0.280s (+0.27%)144.4James Weida-4.301squal -4.459s96.0%qual 95.8%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+11.396squal +10.617s110.6%qual 109.9%1:54.397Stephen Blethen · fastest of 47 · top 5 within 0.9s-2.169s (-1.86%)1:55.929John Heinricy · fastest of 46 · top 5 within 1.0s-0.994s (-0.85%)127.3Alexander Schefer+8.488squal +7.319s107.9%qual 106.8%
36 rule changes (STU: 12, F5: 3, SM: 1, T4: 20)7 weight · 6 tyres & wheels · 3 cars added · 3 suspension & brakes · 2 engine · 2 induction · 1 aero · 4 wording · 8 othershowhide
  • F5 Clarify allowable assisted shifting systems #30871wording
  • F5 Request to correct terminology #30976tyres & wheels
  • STU STU Fender flares #30696tyres & wheels
  • STU Request weight reduction for 12A bridgeport motor in Miata #30751weight -200 lbs
  • T4 Wrong Part Number on 320i Spec Line #30645wording
  • F5 Request to Allow Rotax 593 HO Engine #30712engine
  • T4 Civic Type R Brake Rotors #29817suspension & brakes
  • STU Request for Fender Flare Clarification #30375weight
  • T4 Mini Cooper Spec Line Anomalies #30478weight
  • T4 Request CAI Mustang in T4 #30562induction
  • SM Updates - Obsolete Parts & BOP Parts #30438other
  • STU Provision for Interchangeable Engine Components Already Allowed #30342engine
  • STU ST Oil Coolers E&O Correction to 9.1.4.2.H #30388wording
  • T4 Request consistency review in GCR #30263other
  • STU Super Touring Alternate Miata Hubs #30345tyres & wheels
  • T4 E & O T4 Mustang Wheels #30245tyres & wheels
  • STU Brake Component Relocation #29990suspension & brakes
  • STU Porsche PDK #30081weight
  • STU Reference Letter #29333 Proposed STU 13B Spec Line Changes #30086weight
  • STU Drive Shaft Request #30087other
  • T4 2021 Toyota Supra #29567cars added
  • T4 06-15 MX-5 Durability #29781other
  • T4 Request for Update to T4 Spec Line for Chevrolet Sonic (2011-) #29838induction
  • T4 NC MX-5 06-15 Part Number updates for 2021 #29921weight
  • T4 BMW Z4 2.5L (03-05) Spec Line #30037weight -50 lbs
  • T4 Sway Bars for T4 2016+ MX5 Mazda #30063suspension & brakes
  • T4 Change part numbers on BRZ, FRS lines in T4 #30104wording
  • T4 T4 Mustang Axle Ratio and Wheels #30149tyres & wheels
  • STU 13B Rules Adjustment #29333cars added
  • T4 Request to Classify BMW M2 CS #29523cars added
  • T4 Allow the SpecMX-5 Update Kit Into Touring 4 for the MX-5 #29681other
  • T4 Request Mustang 8.8” rear axle replacement #29860other
  • T4 Cap year range on all 86s #29908other
  • STU Request clarification on wing measurement #29640aero
  • T4 Alfa Romeo 4C Launch Edition #29531other
  • T4 Post Runoffs Feedback for T4 #29752tyres & wheels -50 lbs
Road America Runoffs 20202020-10-022:27.883David Fiorelli · fastest of 14 · top 5 within 4.1s2:28.410Anthony Geraci · fastest of 14 · top 5 within 3.1s144.2David Fiorelli2:20.954Calvin Stewart · fastest of 16 · top 5 within 1.8s2:21.391James Weida · fastest of 14 · top 5 within 1.5s143.2Aaron Ellis-7.019squal -6.929s95.3%qual 95.3%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+15.338squal +14.326s110.3%qual 109.7%2:37.403John Heinricy · fastest of 20 · top 5 within 2.5s2:37.881Chi Ho · fastest of 19 · top 5 within 1.6s130.2Chi Ho+9.471squal +9.520s106.4%qual 106.4%
50 rule changes (STU: 17, F5: 6, SM: 2, T4: 25)9 weight · 7 engine · 7 induction · 5 suspension & brakes · 3 aero · 3 cars added · 2 tyres & wheels · 4 wording · 10 othershowhide
  • F5 Request to Update Suzuki Engine Years for F500 #29453engine
  • SM Radiator E&O Clarifications #29294engine
  • STU Request for Advanced Aero Rule Wording Clarification. #29124aero
  • SM Modifications to prevent failures of Rear Brake Caliper Pin #28953suspension & brakes
  • STU Minimum Weight Determination #27695weight
  • STU ST Gurney flap Wicker clarification #29012aero
  • T4 Scion FRS Solo Spec Coupe Gear Ratio #29021other
  • F5 Request for Cockpit Adjustment of External Jetting Devices #28359other
  • F5 Two Stroke Motors (reply to #28359 WDYT) #28816engine
  • F5 Re letter requesting driver adjustable carb mixture #28840other
  • F5 #28359 WDYT Request for Cockpit Adjustment #28875other
  • STU Request for Alternate Intake Manifold #26514induction
  • STU Request for Addition to GT3 Approved Turbo List #27576induction
  • STU Request BoP for my Car #29004induction
  • STU Sequential Shifters in STU #29031other
  • T4 T4 RX8 bodywork clarification #28941aero
  • T4 2006-2015 MX-5 Clarification #28942tyres & wheels
  • T4 Request to Add a Vehicle to the Roster (contd.) #27698other
  • STU Rotary Help #27833weight
  • T4 Request to Classify 2004 Mercedes Benz 320 CLK #27663cars added
  • T4 Request to change allowed header part # for T4 06-15 Miata #28223wording
  • T4 Z3M Roadster Weight #28437weight
  • STU Request to approve Honda S2000 HKS supercharger #27281engine
  • STU Request BoP on the Lotus #27637weight +100 lbs
  • STU Turbo Inlet Restrictor On MK5 Volkswagen #27704induction
  • STU Honda K20C1 removal #27732induction
  • STU Change GM LNF 2.0 Allowance to LSJ Engine for Viable STL 2.0 #27884engine
  • STU Alternate Engine for Porsche 944 #28259engine
  • STU Please Modify the STU Wheel Size Rule for Clarity #27694weight
  • STU Turbo Engine Cars Base Weight #28032weight
  • T4 Request for 12-13 and 14-15 Honda Civic Springs #27848suspension & brakes
  • T4 Request to Clarify T4 05-10 Mustang Spring Allowance #27899suspension & brakes
  • T4 Request to Allow Brake Upgrade on T4 Mustang #27329suspension & brakes
  • T4 Please Switch the Solstice GXP as Specified in T2, to T3 #27413weight -50 lbs
  • T4 Request to Classify all Mazda RX8 Models in T3/T4 #27606cars added
  • T4 Request for 2014-2018 Mazda 3 GT Brakes #27659suspension & brakes
  • T4 Request to allow aftermarket OEM coolant expansion tank #27763engine
  • T4 Request to allow aftermarket OEM power steering reservoir #27764wording
  • T4 Request for Factory Installed Wings on Subaru BRZ #27831other
  • T4 Request for Replacement Clutches #27892other
  • T4 Request to Classify Chevy Sonic 1.4 In T4 #27906cars added
  • T4 Weight Change Request for 1999 Mazda Miata #28129weight -50 lbs
  • F5 Change 600cc restrictor size #27883induction
  • T4 Clarification of On-Board Fire System for T2 #27183wording
  • T4 Mustang Ecoboost and GT Transmission #27439other
  • T4 BRZ/FRS/86 Tire Size in T4 #27660tyres & wheels
  • T4 NC MX5 2006-2015 Spec Adjustment Request #27739weight -75 lbs
  • T4 T4 RX8 Classification Error #27902wording
  • T4 Request to add Toyota 86 GT to Spec Line #27910other
  • STU Request for an electronic throttle body #27342induction
Virginia International Raceway Runoffs 20192019-10-051:59.948Kevin Boehm · fastest of 25 · top 5 within 3.5s2:00.483Kevin Boehm · fastest of 25 · top 5 within 2.5s143.8Kevin Boehm1:57.361Wiley Mcmahan · fastest of 15 · top 5 within 3.8s1:57.572Wiley Mcmahan · fastest of 15 · top 5 within 4.0s142.8Eric McRee-2.911squal -2.587s97.6%qual 97.8%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+15.976squal +14.604s113.3%qual 112.2%2:11.257John Heinricy · fastest of 25 · top 5 within 0.2s2:10.959Nick Leverone · fastest of 25 · top 5 within 0.6s128.9Tommy Boileau+10.476squal +11.309s108.7%qual 109.4%
42 rule changes (STU: 22, F5: 1, SM: 4, T4: 15)11 weight · 7 induction · 5 cars added · 5 suspension & brakes · 3 aero · 3 engine · 3 tyres & wheels · 4 wording · 1 othershowhide
  • F5 Request for Weight Increase for Motorcycle Powered Cars #27214weight +25 lbs
  • STU Request to correct E&O advanced aerodynamics #27290aero
  • T4 Request spare tire/wheel clarification #27012tyres & wheels
  • T4 Research E&O Mazda MX5 #27112weight
  • STU Remove -2mm penalty from SR20DET Nissan #26982weight
  • STU Request clarification for manifold and throttle in STU #27004induction
  • T4 MR2 Spyder Year Correction #26936wording
  • STU Request to clarify afterrmarket side skirts exhaust exit #26814suspension & brakes
  • STU Wheel Flare wording #26872tyres & wheels
  • T4 Request to allow piggy back ECU on 2000 Mazda Protégé #26085engine
  • T4 Request helper spring as optional #26678suspension & brakes
  • STU Request Ride Height Clarification #26597suspension & brakes
  • STU Request to Use Japanese Mazda 13b Intake Manifold #25790induction
  • STU Request Alternate Intake for Mazda MZR In a Rear Wheel Drive App. #26352induction
  • STU E&O Suspension #26424wording
  • STU Revisit B20 VTEC #26530cars added
  • STU Move Flared Fenders to STU Advanced Aero #26564aero
  • STU TCA Civic SI E&O #26606induction
  • STU S54 Spec line #26620weight
  • T4 Request to classify 2000 - 2001 BMW 323 #25096cars added
  • SM Request to allow aftermarket fuel filters. #26370wording
  • STU Request to Class Assignment for 2017 Civic #24287cars added
  • STU Request to run E46 3246cc in STU #25126weight
  • STU Engine Classification for Rotary #25564engine
  • STU K24/K20 Head Swap Clarification/Amendment #25899induction
  • STU Request to Classify 12a Bridge Ported Rotary Engine #25985cars added
  • STU World Challenge Car Eligibility #26387weight
  • STU Request a phone call for discussion regarding weight #26398weight
  • STU Advanced Aero E&O #26413aero
  • T4 Correct Mazda MX-5 Hard Top Notes #26137weight
  • T4 Consider opening class rules to allow any thermostat #26187wording
  • T4 Cap 2016 Mazda Miata year at 2018 #26388other
  • SM Request 99-00 replacement Wire harnesses #25602engine
  • SM Organize and Clarify 9.1.7.C.1.o. #25913weight
  • SM Strike Tire Tread Language #26123tyres & wheels
  • T4 2012-2015 Honda Civic Si Performance Request #26129suspension & brakes
  • STU Request to Equalize Direct Injected Turbo Cars #24890induction
  • T4 Errors, Omissions, and Updates (Various) #22414weight
  • T4 Request for Adjustments to fiat 124 specline #25371induction
  • T4 Add Clarification to Spec Car Classifications Vehicle Spec #25774weight
  • T4 Clarify Subframe Bushings Permitted for T2-T4 #25800suspension & brakes
  • T4 Consider Solo SSC cross over classification into T4 #25802cars added
Sonoma Raceway Runoffs 20182018-10-101:19.234Franklin Church · fastest of 10 · top 5 within 21.5s1:46.514Kevin Boehm · fastest of 9 · top 5 within 7.4s103.0Franklin Church1:41.807Jeff Jorgenson · fastest of 5 · top 5 within 6.6s1:42.491David Lapham · fastest of 5 · top 5 within 9.5s113.3David Lapham-4.023squal +22.573s96.2%qual 128.5%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+8.764squal +35.121s108.2%qual 144.3%1:52.339Gresham Wagner · fastest of 12 · top 5 within 1.1s1:54.030John Heinricy · fastest of 12 · top 5 within 0.2s106.0Ross Murray+7.516squal +33.105s107.1%qual 141.8%
No rule changes on record between these events
Indianapolis Motor Speedway Runoffs 20172017-09-251:48.921Rob Huffmaster · fastest of 34 · top 5 within 2.0s1:49.387Rob Huffmaster · fastest of 31 · top 5 within 2.4s1:43.136Wiley Clinton McMahan · fastest of 38 · top 5 within 1.4s1:42.860Wiley Clinton McMahan · fastest of 37 · top 5 within 1.6s-6.527squal -5.785s94.0%qual 94.7%1:58.306Chris Haldeman · fastest of 86 · top 5 within 0.5s1:59.100Michael Gagliardo · fastest of 83 · top 5 within 0.6s+9.713squal +9.385s108.9%qual 108.6%1:56.566Oscar Jackson · fastest of 40 · top 5 within 0.6s1:56.923Oscar Jackson · fastest of 38 · top 5 within 1.1s+7.536squal +7.645s106.9%qual 107.0%
No rule changes on record between these events
Mid-Ohio Sports Car Course Runoffs 20162016-09-191:32.738Joe Moser · fastest of 16 · top 5 within 2.5s1:34.597Cameron Maugeri · fastest of 16 · top 5 within 0.8s1:28.528Calvin Stewart · fastest of 14 · top 5 within 3.9s1:29.853Steven Thompson · fastest of 12 · top 5 within 4.5s-4.744squal -4.210s95.0%qual 95.5%1:40.514Justin Hille · fastest of 45 · top 5 within 0.3s1:40.764Michael Carter · fastest of 44 · top 5 within 0.3s+6.167squal +7.776s106.5%qual 108.4%1:38.813Jonathan Yanca · fastest of 34 · top 5 within 2.0s1:40.397Oscar Jackson · fastest of 32 · top 5 within 0.8s+5.800squal +6.075s106.1%qual 106.6%
No rule changes on record between these events
Daytona International Speedway Runoffs 20152015-09-212:05.494Eric Heinrich · fastest of 18 · top 5 within 4.6s2:06.756Eric Heinrich · fastest of 17 · top 5 within 3.5s2:01.824W. Clint McMahan · fastest of 16 · top 5 within 3.0s2:03.298Matthew Strand · fastest of 15 · top 5 within 4.9s-3.458squal -3.670s97.3%qual 97.1%2:18.661Andrew Carbonell · fastest of 62 · top 5 within 0.6s2:24.067Todd Lamb · fastest of 59 · top 5 within 0.8s+17.311squal +13.167s113.7%qual 110.5%2:15.886Philip Royle · fastest of 22 · top 5 within 0.9s2:15.994Philip Royle · fastest of 20 · top 5 within 1.6s+9.238squal +10.392s107.3%qual 108.3%

By track

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