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BoP Lab / Classes / STU

STU vs STL vs SM vs SMX 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)
ASB-SpecEPFAFCFE2FFFPFVFXGT1GT2GTXHPPP2vsSM×vsSMX×SRF3vsSTL×STU×T1T2T3T4Show 51 inactive classes
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 · STL 83.9% of STU Danny Steyn, Virginia International Raceway Runoffs 2022 race · SM 91.3% of STU Travis Wiley, Virginia International Raceway Runoffs 2022 race · SMX 106.4% of STU Ethan Lampe, Road America Runoffs 2024 qualifying

1:402:002:202:4037 rule changes between Runoffs 2018 and Runoffs 201937 ▾30 rule changes between Runoffs 2019 and Runoffs 202030 ▾28 rule changes between Runoffs 2020 and Runoffs 202128 ▾27 rule changes between Runoffs 2021 and Runoffs 202227 ▾6 rule changes between Runoffs 2022 and Runoffs 20236 ▾16 rule changes between Runoffs 2023 and Runoffs 202416 ▾30 rule changes between Runoffs 2024 and Runoffs 202530 ▾23 rule changes between Runoffs 2025 and Runoffs 202623 ▾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)STL race best at Runoffs 2015: 2:10.269 (Kevin Boehm)STL race best at Runoffs 2016: 1:36.625 (Kevin Boehm)STL race best at Runoffs 2017: 1:52.589 (Eric Kutil)STL race best at Runoffs 2018: 1:49.754 (Danny Steyn)STL race best at Runoffs 2019: 2:07.273 (Cliff Ira)STL race best at Runoffs 2020: 2:32.115 (Joe Moser)STL race best at Runoffs 2021: 2:02.711 (Joe Moser)STL race best at Runoffs 2022: 2:07.832 (Danny Steyn)STL race best at Runoffs 2023: 2:06.682 (Joe Moser)STL race best at Runoffs 2024: 2:30.245 (Joe Moser)STL race best at Runoffs 2025: 2:32.127 (Jose Osiris Pena)STL race best at Runoffs 2026: 2:30.657 (Danny Steyn)STL qualifying best at Runoffs 2015: 2:09.672 (Kevin Boehm)STL qualifying best at Runoffs 2016: 1:35.439 (John Schmitt)STL qualifying best at Runoffs 2017: 1:52.647 (Adam Roberts)STL qualifying best at Runoffs 2018: 1:49.138 (Danny Steyn)STL qualifying best at Runoffs 2019: 2:07.203 (Danny Steyn)STL qualifying best at Runoffs 2020: 2:31.420 (Danny Steyn)STL qualifying best at Runoffs 2021: 1:51.665 (Danny Steyn)STL qualifying best at Runoffs 2022: 2:05.474 (Danny Steyn)STL qualifying best at Runoffs 2023: 2:05.779 (Danny Steyn)STL qualifying best at Runoffs 2024: 2:30.063 (Joe Moser)STL qualifying best at Runoffs 2025: 2:32.065 (Jose Osiris Pena)STL qualifying best at Runoffs 2026: 2:30.537 (Derek Ketchie)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)SMX race best at Runoffs 2023: 2:12.616 (Noah Harmon)SMX race best at Runoffs 2024: 2:36.278 (Ethan Jacobs)SMX race best at Runoffs 2025: 2:37.091 (Michael Tinis)SMX race best at Runoffs 2026: 2:36.414 (Cam Ebben)SMX qualifying best at Runoffs 2023: 2:11.435 (Nathan Nicholson)SMX qualifying best at Runoffs 2024: 2:35.651 (Ethan Lampe)SMX qualifying best at Runoffs 2025: 2:36.232 (Cam Ebben)SMX qualifying best at Runoffs 2026: 2:36.472 (Skyler Cottrell)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
STUSTLSMSMXsolid race · dashed qualifying · slower is lower
100%105%110%115%37 rule changes between Runoffs 2018 and Runoffs 201937 ▾30 rule changes between Runoffs 2019 and Runoffs 202030 ▾28 rule changes between Runoffs 2020 and Runoffs 202128 ▾27 rule changes between Runoffs 2021 and Runoffs 202227 ▾6 rule changes between Runoffs 2022 and Runoffs 20236 ▾16 rule changes between Runoffs 2023 and Runoffs 202416 ▾30 rule changes between Runoffs 2024 and Runoffs 202530 ▾23 rule changes between Runoffs 2025 and Runoffs 202623 ▾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)STL race best at Runoffs 2015: 102.8% of STU's (Kevin Boehm)STL race best at Runoffs 2016: 102.1% of STU's (Kevin Boehm)STL race best at Runoffs 2017: 102.9% of STU's (Eric Kutil)STL race best at Runoffs 2018: 103.0% of STU's (Danny Steyn)STL race best at Runoffs 2019: 105.6% of STU's (Cliff Ira)STL race best at Runoffs 2020: 102.5% of STU's (Joe Moser)STL race best at Runoffs 2021: 114.2% of STU's (Joe Moser)Off the chart: STL race best at Runoffs 2022: 83.9% of STU's (Danny Steyn)STL race best at Runoffs 2023: 103.6% of STU's (Joe Moser)STL race best at Runoffs 2024: 103.0% of STU's (Joe Moser)STL race best at Runoffs 2025: 105.3% of STU's (Jose Osiris Pena)STL race best at Runoffs 2026: 102.9% of STU's (Danny Steyn)STL qualifying best at Runoffs 2015: 103.3% of STU's (Kevin Boehm)STL qualifying best at Runoffs 2016: 102.9% of STU's (John Schmitt)STL qualifying best at Runoffs 2017: 103.4% of STU's (Adam Roberts)Off the chart: STL qualifying best at Runoffs 2018: 137.7% of STU's (Danny Steyn)STL qualifying best at Runoffs 2019: 106.0% of STU's (Danny Steyn)STL qualifying best at Runoffs 2020: 102.4% of STU's (Danny Steyn)STL qualifying best at Runoffs 2021: 104.3% of STU's (Danny Steyn)STL qualifying best at Runoffs 2022: 104.0% of STU's (Danny Steyn)STL qualifying best at Runoffs 2023: 104.5% of STU's (Danny Steyn)STL qualifying best at Runoffs 2024: 102.6% of STU's (Joe Moser)STL qualifying best at Runoffs 2025: 106.3% of STU's (Jose Osiris Pena)STL qualifying best at Runoffs 2026: 103.9% of STU's (Derek Ketchie)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)SMX race best at Runoffs 2023: 108.4% of STU's (Noah Harmon)SMX race best at Runoffs 2024: 107.2% of STU's (Ethan Jacobs)SMX race best at Runoffs 2025: 108.7% of STU's (Michael Tinis)SMX race best at Runoffs 2026: 106.8% of STU's (Cam Ebben)SMX qualifying best at Runoffs 2023: 109.2% of STU's (Nathan Nicholson)SMX qualifying best at Runoffs 2024: 106.4% of STU's (Ethan Lampe)SMX qualifying best at Runoffs 2025: 109.2% of STU's (Cam Ebben)SMX qualifying best at Runoffs 2026: 108.0% of STU's (Skyler Cottrell)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
STUSTLSMSMXsolid 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
EventSTUSTLSMSMX
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%)2:30.537Derek Ketchie · fastest of 16 · top 5 within 2.9s-1.528s (-1.00%)2:30.657Danny Steyn · fastest of 16 · top 5 within 0.6s-1.470s (-0.97%)134.8Mike Taylor+2.6 mph (+2.0%)+4.241squal +5.625s102.9%qual 103.9%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%2:36.472Skyler Cottrell · fastest of 21 · top 5 within 0.4s+0.240s (+0.15%)2:36.414Cam Ebben · fastest of 21 · top 5 within 1.1s-0.677s (-0.43%)128.4Christian Hoagland-0.6 mph (-0.5%)+9.998squal +11.560s106.8%qual 108.0%
23 rule changes (STU: 15, STL: 4, SM: 2, SMX: 2)10 weight · 4 induction · 3 tyres & wheels · 1 engine · 1 removed · 2 wording · 2 othershowhide
  • STU Wheel and tire requirements for GT3U #40679tyres & wheels
  • SM Rear Toe Link #40271other
  • SMX Rear Toe Link #40271other
  • STL Spec Line Clean Up #40344removed
  • STU 9” Wheels #40433tyres & wheels
  • STU Weight adjustment to former GT3U cars #40474weight
  • STL Calculating Weight #40224weight
  • STU Request to allow BMW M50B20TU engine in STU #40202engine
  • STU Calculating Weight #40224weight
  • STU Turbo Restrictor Size Increase Request #40008induction
  • STU GT86 Cups Car in STU #40028weight
  • SM Part Number Change Request #39914wording
  • SMX Part Number Change Request #39914wording
  • STL Classifications #39885weight
  • STU Mazda Rx-8 Renesis - Streetported Variant & Added Weight #39785weight
  • STU Eliminate 33 and 34 mm TIRs #39872weight
  • STU Fab 9 Racing Intake Manifold in STU #39767induction
  • STL Weight adjustment for STL #39579weight
  • STU Request for Permission on Aftermarket Turbo Kit and Intake #39529induction
  • STU Turbo Inlet Restrictor Table #38961induction
  • STU 275 Tire Rule #38983tyres & wheels
  • STU STU Honda Engine weight penalty #39375weight
  • STU Non-Homologated Engine Swaps - Specifically K24A2 w/ Honda CRZ #38746weight
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%)2:32.065Jose Osiris Pena · fastest of 14 · top 5 within 3.4s+2.002s (+1.33%)2:32.127Jose Osiris Pena · fastest of 13 · top 5 within 2.4s+1.882s (+1.25%)132.2Jon Sewell-2.1 mph (-1.5%)+7.630squal +8.982s105.3%qual 106.3%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%2:36.232Cam Ebben · fastest of 20 · top 5 within 0.2s+0.581s (+0.37%)2:37.091Michael Tinis · fastest of 19 · top 5 within 0.3s+0.813s (+0.52%)129.1Camden Gruber-0.4 mph (-0.3%)+12.594squal +13.149s108.7%qual 109.2%
30 rule changes (STU: 18, STL: 3, SM: 4, SMX: 5)9 weight · 6 tyres & wheels · 3 engine · 1 cars added · 1 induction · 3 wording · 7 othershowhide
  • STU Lotus Weight Reduction E&O #38919weight
  • STL Lotus Weight Reduction #38772weight -50 lbs
  • STU STU-TCR Adjustments #38723weight
  • STU Lotus Weight Reduction #38772weight -50 lbs
  • 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
  • SM SMX Data Submission - Penalties #38248other
  • SM SMX Penaly Clarification updated language #38337wording
  • SMX SMX Data Submission - Penalties #38248other
  • SMX SMX Penaly Clarification updated language #38337wording
  • SM Clarify Tire Marking Regs #38005tyres & wheels
  • SMX Clarify Tire Marking Regs #38004tyres & wheels
  • SMX SMX Data Submission Timeframe #38039other
  • STL E&O: SMX Allowance in STL #37945weight
  • STU Wheel Size Inconsistency #38018tyres & wheels
  • STU Table C: STU-GT3U Clarification #38268weight
  • 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
  • STU Audi 1.8t Wagon STU Table B #36685weight
  • STU Merger GT3 to STU #37486other
  • STU GT3 TCR Tire allowance #37494tyres & wheels
  • SM E&O SMX Regs 9.1.7.1.D.5.u-.w #37070other
  • SMX E&O SMX Regs 9.1.7.1.D.5.u-.w #37070other
  • STL Request to Remove Miata Hubs from General category #37138tyres & wheels
  • STU Request to Remove Miata Hubs from General category #37138tyres & wheels
  • STU BMW N54/N55 Engine Allowance #37146engine
  • STU R53 15% Pulley Request #36980other
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%)2:30.063Joe Moser · fastest of 18 · top 5 within 3.7s-1.357s (-0.90%)2:30.245Joe Moser · fastest of 16 · top 5 within 4.2s-1.870s (-1.23%)134.3Joe Moser+1.3 mph (+1.0%)+4.421squal +3.836s103.0%qual 102.6%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%2:35.651Ethan Lampe · fastest of 23 · top 5 within 0.7s2:36.278Ethan Jacobs · fastest of 22 · top 5 within 0.7s129.5Michael Borden+10.454squal +9.424s107.2%qual 106.4%
16 rule changes (STU: 4, STL: 4, SM: 4, SMX: 4)3 induction · 2 engine · 2 suspension & brakes · 2 weight · 2 wording · 5 othershowhide
  • SM SMX Camera Rule Correction #36496wording
  • SM AIM ECU Protocol #36556engine
  • SM OE versus OEM Definitons #36608other
  • SM Shifter Bushing #36611suspension & brakes
  • SMX SMX Camera Rule Correction #36496wording
  • SMX AIM ECU Protocol #36556engine
  • SMX OE versus OEM Definitons #36608other
  • SMX Shifter Bushing #36611suspension & brakes
  • STU RWD Turbo Disadvantage #36255induction
  • STU Letter #35397 addendum #35453weight
  • STU S54 Drysump #35464other
  • STL ST Electric-Assisted Steering Systems #35066other
  • STL BOP Adjustments #35112weight
  • STL Mazda 12A #35320induction
  • STU ST Electric-Assisted Steering Systems #35066other
  • STL Alternate Carburetor Request for 79-85 RX7 12a #35181induction
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%)2:05.779Danny Steyn · fastest of 22 · top 5 within 3.4s+0.305s (+0.24%)2:06.682Joe Moser · fastest of 20 · top 5 within 1.5s-1.150s (-0.90%)131.8Danny Steyn+0.1 mph (+0.1%)+4.380squal +5.390s103.6%qual 104.5%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%2:11.435Nathan Nicholson · fastest of 18 · top 5 within 0.6s2:12.616Noah Harmon · fastest of 16 · top 5 within 0.1s127.8Noah Harmon+10.314squal +11.046s108.4%qual 109.2%
6 rule changes (STU: 3, STL: 2, SM: 1)2 tyres & wheels · 2 weight · 1 cars added · 1 inductionshowhide
  • STU 2022 Toyota GR Cup for STU #34449cars added
  • STL Clarify STL table B - IT spec notes on Tires #34187tyres & wheels
  • STU Alternate OEM Miata Intake Manifold #33827induction
  • STU E&O STU NA Weight Chart. #33737weight
  • SM BOP for NB1 and NB2 #32309weight
  • STL Spec MX5 in STL #33473tyres & wheels
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%)2:05.474Danny Steyn · fastest of 24 · top 5 within 2.3s-1.729s (-1.36%)2:07.832Danny Steyn · fastest of 22 · top 5 within 1.9s+0.559s (+0.44%)131.7Trever Degioanni-3.2 mph (-2.3%)-24.525squal +4.859s83.9%qual 104.0%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%
27 rule changes (STU: 21, STL: 5, SM: 1)9 weight · 4 engine · 4 induction · 2 cars added · 2 tyres & wheels · 1 aero · 1 suspension & brakes · 1 wording · 3 othershowhide
  • STU Request Mazda 13 B turbo #32668induction
  • STU Hood Vents and Intercooler Scoops #32733other
  • STU Non 4 valve weight reduction removed #32808weight
  • STU Error in new minimum weight table when combined with other text #32711weight
  • STU Redundant Language in May GCR #32713engine
  • STU Opposed to the Proposed STU Weight Chart #32381weight
  • STU Clarification request for GCR 9.1.4.D.3.a Splitter Definition #32414aero
  • 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
  • STL Single TB Weight Modifiers #31449weight
  • STL Improved Touring Tires #32063tyres & wheels
  • 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
  • STU Request Allowance for Balance Shaft Delete in STU #31434engine
  • STU Request Louvers in hood vents #31916other
  • STL Throttling Device Clarification #31323induction
  • STL Mazda Renesis Restriction #31467induction
  • STL Clarification of 79-85 RX7 Spec line #31621wording
  • STU Request to Add Honda K23 Spec Line #30682cars added
  • STU RE: Aug FT letter 30682 #31060other
  • STU Throttling Device Clarification #31323induction
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 VanSteenburg1:51.665Danny Steyn · fastest of 42 · top 5 within 1.7s-0.982s (-0.87%)2:02.711Joe Moser · fastest of 37 · top 5 within 3.2s+10.122s (+8.99%)131.8Max Gee+15.270squal +4.587s114.2%qual 104.3%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+11.396squal +10.617s110.6%qual 109.9%
28 rule changes (STU: 12, STL: 15, SM: 1)6 weight · 3 aero · 3 engine · 3 suspension & brakes · 3 tyres & wheels · 2 cars added · 2 induction · 2 wording · 4 othershowhide
  • STL Request to clean up Spec MX-5 Redundancy #31069other
  • STU STU Fender flares #30696tyres & wheels
  • STU Request weight reduction for 12A bridgeport motor in Miata #30751weight -200 lbs
  • STL VW Engine Request #30625engine
  • STL Solstice Ride Height #30183suspension & brakes
  • STL Request Mazda B5 DOHC #30420cars added
  • STL Honda B16A (JDM) Restrictor change #30531induction
  • STU Request for Fender Flare Clarification #30375weight
  • SM Updates - Obsolete Parts & BOP Parts #30438other
  • STL ST Oil Coolers E&O Correction to 9.1.4.2.H #30388wording
  • STU Provision for Interchangeable Engine Components Already Allowed #30342engine
  • STU ST Oil Coolers E&O Correction to 9.1.4.2.H #30388wording
  • STL GM Ecotec engines in STL #30247engine
  • STL Super Touring Alternate Miata Hubs #30345tyres & wheels
  • STU Super Touring Alternate Miata Hubs #30345tyres & wheels
  • STL Brake Component Relocation #29990suspension & brakes
  • STL Super Touring Wing Clarification #30111aero
  • STL Transmission Options #30118other
  • 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
  • STL Request for FWD and RWD Parity #29728weight
  • STL Request to Remove Honda F20C 2% Weight Penalty #29815weight
  • STL Request for FWD and RWD Parity #30023induction
  • STU 13B Rules Adjustment #29333cars added
  • STL Request clarification on wing measurement #29640aero
  • STU Request clarification on wing measurement #29640aero
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 Fiorelli2:31.420Danny Steyn · fastest of 33 · top 5 within 3.1s2:32.115Joe Moser · fastest of 30 · top 5 within 1.5s132.9Darin Treakle+3.705squal +3.537s102.5%qual 102.4%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%
30 rule changes (STU: 17, STL: 11, SM: 2)10 induction · 6 engine · 6 weight · 3 aero · 1 cars added · 1 suspension & brakes · 1 tyres & wheels · 1 wording · 1 othershowhide
  • 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
  • STL Minimum Weight Determination #27695weight
  • STL ST Gurney flap Wicker clarification #29012aero
  • STU Minimum Weight Determination #27695weight
  • STU ST Gurney flap Wicker clarification #29012aero
  • STL Request for Addition to GT3 Approved Turbo List #27576induction
  • 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
  • STL Request to add 2016-2019 GMX-5 Spec line #28604cars added
  • STL Request to update PN for MX-5 #28622wording
  • STL Correction - Clarification Honda/Acura B18B engine Letter # 26209 #28873engine
  • STU Rotary Help #27833weight
  • STL STL Honda B18 restrictor changes #28794induction
  • STL Change GM LNF 2.0 Allowance to LSJ Engine for Viable STL 2.0 #27884engine
  • STL Acura/Honda B18C engine chart. Reduce the current 54 mm flat plat #28663induction
  • STL Mazda MZR engine chart. Reduce the current 55 mm flat plate to 53 #28664induction
  • 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
  • STL Request to add wheel part numbers #28342tyres & wheels
  • STU Please Modify the STU Wheel Size Rule for Clarity #27694weight
  • STU Turbo Engine Cars Base Weight #28032weight
  • 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 Boehm2:07.203Danny Steyn · fastest of 36 · top 5 within 1.8s2:07.273Cliff Ira · fastest of 35 · top 5 within 1.4s134.8Cliff Ira+6.790squal +7.255s105.6%qual 106.0%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%
37 rule changes (STU: 22, STL: 11, SM: 4)10 weight · 8 induction · 4 cars added · 4 suspension & brakes · 3 aero · 3 engine · 2 tyres & wheels · 3 wordingshowhide
  • STL Request to Classify Spec MX-5 Challenge in STL #27399cars added
  • STU Request to correct E&O advanced aerodynamics #27290aero
  • STL Request clarification for manifold and throttle in STU #27004induction
  • STU Remove -2mm penalty from SR20DET Nissan #26982weight
  • STU Request clarification for manifold and throttle in STU #27004induction
  • STL Request Restrictor Plate correction #26779induction
  • STU Request to clarify afterrmarket side skirts exhaust exit #26814suspension & brakes
  • STU Wheel Flare wording #26872tyres & wheels
  • STL Request Ride Height Clarification #26597suspension & 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
  • SM Request to allow aftermarket fuel filters. #26370wording
  • STL Request to Allow VW 1.8L Engine #25614engine
  • STL Request to reduce weight of RX8 with Renesis rotary #25781weight -100 lbs
  • STL Request for Open Brake Pads On Mazda MX-5 Cup NC #25821suspension & brakes
  • STL Request to clarify B18C1 GSR Honda B motor table #26209weight
  • STL Port Matching #26415wording
  • 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
  • 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
  • STL Request to equalize FPR Reduction on all B-Series Vtec Engines #24746weight
  • STL Request E&O for Mazda Miata Spec Line #25955weight
  • STU Request to Equalize Direct Injected Turbo Cars #24890induction
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 Church1:49.138Danny Steyn · fastest of 19 · top 5 within 2.5s1:49.754Danny Steyn · fastest of 17 · top 5 within 2.5s103.2Craig McHaffie+3.240squal +29.904s103.0%qual 137.7%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%
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 2.4s1:52.647Adam Roberts · fastest of 57 · top 5 within 0.8s1:52.589Eric Kutil · fastest of 50 · top 5 within 1.2s+3.202squal +3.726s102.9%qual 103.4%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%
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 0.8s1:35.439John Schmitt · fastest of 34 · top 5 within 1.5s1:36.625Kevin Boehm · fastest of 31 · top 5 within 0.6s+2.028squal +2.701s102.1%qual 102.9%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%
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 3.5s2:09.672Kevin Boehm · fastest of 37 · top 5 within 2.5s2:10.269Kevin Boehm · fastest of 37 · top 5 within 2.1s+3.513squal +4.178s102.8%qual 103.3%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%

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.