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BoP Lab / Classes / STL

STL vs FM vs T4 vs FB pace at every track

Lap times across years say as much about the weather as the class. % of STL is each class's best lap as a share of STL'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-SpecEPFAvsFB×FCFE2FFvsFM×FPFVFXGT1GT2GTXHPPP2SMSMXSRF3STL×STUT1T2T3vsT4×Show 49 inactive classes
Series
Reference · what % is measured against
Tracks · untick to narrow

Closest to the field: STL 100.0% of STL Kevin Boehm, Daytona International Speedway Runoffs 2015 race · FM 89.2% of STL Bryce Cornet, Sonoma Raceway Runoffs 2018 race · T4 94.5% of STL John Heinricy, Indianapolis Motor Speedway Runoffs 2021 race · FB 81.2% of STL J R Osborne, Sonoma Raceway Runoffs 2018 qualifying

1:201:402:002:202:4026 rule changes between Runoffs 2018 and Runoffs 201926 ▾36 rule changes between Runoffs 2019 and Runoffs 202036 ▾35 rule changes between Runoffs 2020 and Runoffs 202135 ▾34 rule changes between Runoffs 2021 and Runoffs 202234 ▾22 rule changes between Runoffs 2022 and Runoffs 202322 ▾32 rule changes between Runoffs 2023 and Runoffs 202432 ▾32 rule changes between Runoffs 2024 and Runoffs 202532 ▾30 rule changes between Runoffs 2025 and Runoffs 202630 ▾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)FM race best at Runoffs 2015: 1:58.029 (Joseph Burton-Harris)FM race best at Runoffs 2016: 1:27.922 (Jacob Loomis)FM race best at Runoffs 2017: 1:41.146 (Jarret Voorhies)FM race best at Runoffs 2018: 1:37.909 (Bryce Cornet)FM race best at Runoffs 2019: 2:15.816 (Bryce Cornet)FM qualifying best at Runoffs 2015: 1:57.804 (Joseph Burton-Harris)FM qualifying best at Runoffs 2016: 1:26.043 (Jacob Loomis)FM qualifying best at Runoffs 2017: 1:41.231 (Jarret Voorhies)FM qualifying best at Runoffs 2018: 1:37.598 (Bryce Cornet)FM qualifying best at Runoffs 2019: 1:55.124 (Bryce Cornet)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)FB race best at Runoffs 2015: 1:51.616 (J R Osborne)FB race best at Runoffs 2016: 1:21.015 (Jeremy Hill)FB race best at Runoffs 2017: 1:33.702 (Alex Mayer)FB race best at Runoffs 2018: 1:31.189 (J R Osborne)FB race best at Runoffs 2019: 1:57.688 (Pete Frost)FB qualifying best at Runoffs 2015: 1:50.711 (J R Osborne)FB qualifying best at Runoffs 2016: 1:19.886 (Alex Mayer)FB qualifying best at Runoffs 2017: 1:33.746 (Gary Hickman)FB qualifying best at Runoffs 2018: 1:28.612 (J R Osborne)FB qualifying best at Runoffs 2019: 1:54.469 (Pete Frost)Daytona International Speedway · Runoffs 2015R2015Mid-Ohio Sports Car Course · Runoffs 2016R2016Indianapolis Motor Speedway · Runoffs 2017R2017Sonoma Raceway · Runoffs 2018R2018Virginia International Raceway · Runoffs 2019R2019Road America · Runoffs 2020R2020Indianapolis Motor Speedway · Runoffs 2021R2021Virginia International Raceway · Runoffs 2022R2022Virginia International Raceway · Runoffs 2023R2023Road America · Runoffs 2024R2024Road America · Runoffs 2025R2025Road America · Runoffs 2026R2026
STLFMT4FBsolid race · dashed qualifying · slower is lower
85%90%95%100%105%26 rule changes between Runoffs 2018 and Runoffs 201926 ▾36 rule changes between Runoffs 2019 and Runoffs 202036 ▾35 rule changes between Runoffs 2020 and Runoffs 202135 ▾34 rule changes between Runoffs 2021 and Runoffs 202234 ▾22 rule changes between Runoffs 2022 and Runoffs 202322 ▾32 rule changes between Runoffs 2023 and Runoffs 202432 ▾32 rule changes between Runoffs 2024 and Runoffs 202532 ▾30 rule changes between Runoffs 2025 and Runoffs 202630 ▾STL race best at Runoffs 2015: 100.0% of STL's (Kevin Boehm)STL race best at Runoffs 2016: 100.0% of STL's (Kevin Boehm)STL race best at Runoffs 2017: 100.0% of STL's (Eric Kutil)STL race best at Runoffs 2018: 100.0% of STL's (Danny Steyn)STL race best at Runoffs 2019: 100.0% of STL's (Cliff Ira)STL race best at Runoffs 2020: 100.0% of STL's (Joe Moser)STL race best at Runoffs 2021: 100.0% of STL's (Joe Moser)STL race best at Runoffs 2022: 100.0% of STL's (Danny Steyn)STL race best at Runoffs 2023: 100.0% of STL's (Joe Moser)STL race best at Runoffs 2024: 100.0% of STL's (Joe Moser)STL race best at Runoffs 2025: 100.0% of STL's (Jose Osiris Pena)STL race best at Runoffs 2026: 100.0% of STL's (Danny Steyn)STL qualifying best at Runoffs 2015: 100.0% of STL's (Kevin Boehm)STL qualifying best at Runoffs 2016: 100.0% of STL's (John Schmitt)STL qualifying best at Runoffs 2017: 100.0% of STL's (Adam Roberts)STL qualifying best at Runoffs 2018: 100.0% of STL's (Danny Steyn)STL qualifying best at Runoffs 2019: 100.0% of STL's (Danny Steyn)STL qualifying best at Runoffs 2020: 100.0% of STL's (Danny Steyn)STL qualifying best at Runoffs 2021: 100.0% of STL's (Danny Steyn)STL qualifying best at Runoffs 2022: 100.0% of STL's (Danny Steyn)STL qualifying best at Runoffs 2023: 100.0% of STL's (Danny Steyn)STL qualifying best at Runoffs 2024: 100.0% of STL's (Joe Moser)STL qualifying best at Runoffs 2025: 100.0% of STL's (Jose Osiris Pena)STL qualifying best at Runoffs 2026: 100.0% of STL's (Derek Ketchie)FM race best at Runoffs 2015: 90.6% of STL's (Joseph Burton-Harris)FM race best at Runoffs 2016: 91.0% of STL's (Jacob Loomis)FM race best at Runoffs 2017: 89.8% of STL's (Jarret Voorhies)FM race best at Runoffs 2018: 89.2% of STL's (Bryce Cornet)FM race best at Runoffs 2019: 106.7% of STL's (Bryce Cornet)FM qualifying best at Runoffs 2015: 90.8% of STL's (Joseph Burton-Harris)FM qualifying best at Runoffs 2016: 90.2% of STL's (Jacob Loomis)FM qualifying best at Runoffs 2017: 89.9% of STL's (Jarret Voorhies)FM qualifying best at Runoffs 2018: 89.4% of STL's (Bryce Cornet)FM qualifying best at Runoffs 2019: 90.5% of STL's (Bryce Cornet)T4 race best at Runoffs 2015: 104.4% of STL's (Philip Royle)T4 race best at Runoffs 2016: 103.9% of STL's (Oscar Jackson)T4 race best at Runoffs 2017: 103.8% of STL's (Oscar Jackson)T4 race best at Runoffs 2018: 103.9% of STL's (John Heinricy)T4 race best at Runoffs 2019: 102.9% of STL's (Nick Leverone)T4 race best at Runoffs 2020: 103.8% of STL's (Chi Ho)T4 race best at Runoffs 2021: 94.5% of STL's (John Heinricy)Off the chart: T4 race best at Runoffs 2022: 113.8% of STL's (John Heinricy)T4 race best at Runoffs 2023: 104.2% of STL's (Devin Anderson)T4 race best at Runoffs 2024: 102.6% of STL's (Alex Lozano)T4 race best at Runoffs 2025: 100.3% of STL's (Alex Lozano)T4 race best at Runoffs 2026: 103.4% of STL's (Matt Spicuzzi)T4 qualifying best at Runoffs 2015: 104.8% of STL's (Philip Royle)T4 qualifying best at Runoffs 2016: 103.5% of STL's (Jonathan Yanca)T4 qualifying best at Runoffs 2017: 103.5% of STL's (Oscar Jackson)T4 qualifying best at Runoffs 2018: 102.9% of STL's (Gresham Wagner)T4 qualifying best at Runoffs 2019: 103.2% of STL's (John Heinricy)T4 qualifying best at Runoffs 2020: 104.0% of STL's (John Heinricy)T4 qualifying best at Runoffs 2021: 102.4% of STL's (Stephen Blethen)T4 qualifying best at Runoffs 2022: 103.3% of STL's (John Heinricy)T4 qualifying best at Runoffs 2023: 103.8% of STL's (Devin Anderson)T4 qualifying best at Runoffs 2024: 102.9% of STL's (Matt Spicuzzi)T4 qualifying best at Runoffs 2025: 100.6% of STL's (Matt Spicuzzi)T4 qualifying best at Runoffs 2026: 103.5% of STL's (Matt Spicuzzi)FB race best at Runoffs 2015: 85.7% of STL's (J R Osborne)FB race best at Runoffs 2016: 83.8% of STL's (Jeremy Hill)FB race best at Runoffs 2017: 83.2% of STL's (Alex Mayer)FB race best at Runoffs 2018: 83.1% of STL's (J R Osborne)FB race best at Runoffs 2019: 92.5% of STL's (Pete Frost)FB qualifying best at Runoffs 2015: 85.4% of STL's (J R Osborne)FB qualifying best at Runoffs 2016: 83.7% of STL's (Alex Mayer)FB qualifying best at Runoffs 2017: 83.2% of STL's (Gary Hickman)FB qualifying best at Runoffs 2018: 81.2% of STL's (J R Osborne)FB qualifying best at Runoffs 2019: 90.0% of STL's (Pete Frost)Daytona International Speedway · Runoffs 2015R2015Mid-Ohio Sports Car Course · Runoffs 2016R2016Indianapolis Motor Speedway · Runoffs 2017R2017Sonoma Raceway · Runoffs 2018R2018Virginia International Raceway · Runoffs 2019R2019Road America · Runoffs 2020R2020Indianapolis Motor Speedway · Runoffs 2021R2021Virginia International Raceway · Runoffs 2022R2022Virginia International Raceway · Runoffs 2023R2023Road America · Runoffs 2024R2024Road America · Runoffs 2025R2025Road America · Runoffs 2026R2026
STLFMT4FBsolid race · dashed qualifying · each class's best lap as a share of STL's at the same event (the reference class, changeable above); 100% is level, less is quicker, so up the chart is quicker
EventSTLFMT4FB
Qual best Race best Trap Qual best Race best Trap vs STL % of STL Qual best Race best Trap vs STL % of STL Qual best Race best Trap vs STL % of STL 
Road America Runoffs 20262026-09-282:30.537Derek 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%)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%)+5.100squal +5.339s103.4%qual 103.5%
30 rule changes (STL: 4, T4: 26)8 weight · 5 cars added · 5 suspension & brakes · 3 induction · 2 removed · 2 tyres & wheels · 5 othershowhide
  • 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
  • STL Spec Line Clean Up #40344removed
  • T4 Dodge Neon DOHC Weight #40329weight
  • STL 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
  • T4 2003 Honda Civic Si Classification #39999cars added
  • STL Classifications #39885weight
  • T4 16-24 ND MX5 T4 #39934suspension & brakes
  • 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
  • STL Weight adjustment for STL #39579weight
  • T4 Alternate Placement of Fuse Panel and Electronics Request #39370other
  • T4 Clarify T4 Brake Rotor Allowance #39503suspension & brakes
  • T4 Classing 1995-99 Dodge Neon SOHC #39285cars added
  • 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 20252025-09-292:32.065Jose 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%)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%)+0.506squal +0.891s100.3%qual 100.6%
32 rule changes (STL: 3, T4: 29)8 weight · 5 cars added · 5 tyres & wheels · 2 engine · 2 suspension & brakes · 1 aero · 1 induction · 2 wording · 6 othershowhide
  • STL Lotus Weight Reduction #38772weight -50 lbs
  • T4 Incorrect Touring Heading #38451wording
  • T4 Allow B-Spec cars to run in T4 #38439other
  • T4 T4 Mustang #38059weight -100 lbs
  • T4 SSC tire allowance #38216tyres & wheels
  • STL E&O: SMX Allowance in STL #37945weight
  • T4 Correct Ring and Pinion Ratio to T3, Sorry I Mean T4 3.7 V6 Stang #38041wording
  • T4 T4 Mustang #38058aero
  • T4 Ford Mustang V6 (05-14) #37516other
  • T4 Request to Classify Club Spec in Appropriate Touring Classes #37523cars added
  • T4 Remove spec lines that have expired #37269induction
  • T4 2016-2018 Mazda Miata MX5 #37085weight -75 lbs
  • STL Request to Remove Miata Hubs from General category #37138tyres & wheels
  • 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
  • T4 Bop Request 06-11 Honda Civic Si #37013other
Road America Runoffs 20242024-10-012:30.063Joe 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%)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%)+3.963squal +4.367s102.6%qual 102.9%
32 rule changes (STL: 4, T4: 28)10 weight · 5 induction · 5 suspension & brakes · 2 aero · 2 cars added · 1 engine · 1 removed · 6 othershowhide
  • 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
  • T4 Reorganize Spec Lines #35375induction
  • T4 Allow any 400lb rear spring in the RX8 #35433suspension & brakes
  • T4 370Z Brake Rotor Size Correction #35487suspension & brakes
  • STL ST Electric-Assisted Steering Systems #35066other
  • STL BOP Adjustments #35112weight
  • STL Mazda 12A #35320induction
  • 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
  • STL Alternate Carburetor Request for 79-85 RX7 12a #35181induction
  • 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 20232023-09-232:05.779Danny 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%)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%)+5.280squal +4.735s104.2%qual 103.8%
22 rule changes (STL: 2, T4: 20)6 weight · 4 suspension & brakes · 3 tyres & wheels · 2 cars added · 1 induction · 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
  • T4 2002-2006 Mini Cooper S R53 Spec Line Request #34336weight -50 lbs
  • STL Clarify STL table B - IT spec notes on Tires #34187tyres & wheels
  • T4 05-06 Mini Wheel Weight #34112weight
  • T4 06-09 VW Rabbit #34153induction
  • T4 96-01 Audi a4 2.8 Spring Rate #34217suspension & brakes
  • T4 Request to Classify 2004-2008 Acura TSX in T4 #33590cars added
  • T4 T4 Mustang Brakes/Swaybar #34036suspension & brakes
  • 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
  • STL Spec MX5 in STL #33473tyres & wheels
  • 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 20222022-09-242:05.474Danny 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%)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%)+17.611squal +4.103s113.8%qual 103.3%
34 rule changes (STL: 5, T4: 29)8 suspension & brakes · 6 tyres & wheels · 5 weight · 3 induction · 2 cars added · 2 engine · 1 removed · 3 wording · 4 othershowhide
  • T4 04-09 Mazda3 Balance Shaft Delete Kit #32795other
  • T4 Request Wider Wheels for Hyundai Tiburon #32536tyres & wheels
  • 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
  • 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
  • STL Single TB Weight Modifiers #31449weight
  • STL Improved Touring Tires #32063tyres & wheels
  • T4 Reply to letter #31486/29879 T2-T4 Grill openings #31935suspension & brakes
  • T4 BRZ vs BRZ TS #32022tyres & wheels
  • T4 MX-5 Durability Detailed #31102weight
  • T4 Request Allowances for 2005 - 2010 Mustang #31624wording
  • STL Throttling Device Clarification #31323induction
  • STL Mazda Renesis Restriction #31467induction
  • STL Clarification of 79-85 RX7 Spec line #31621wording
  • 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 20212021-09-251:51.665Danny 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 Gee1:54.397Stephen 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-6.782squal +2.732s94.5%qual 102.4%
35 rule changes (STL: 15, T4: 20)5 weight · 4 induction · 4 suspension & brakes · 4 tyres & wheels · 3 cars added · 2 aero · 2 engine · 3 wording · 8 othershowhide
  • STL Request to clean up Spec MX-5 Redundancy #31069other
  • T4 Wrong Part Number on 320i Spec Line #30645wording
  • STL VW Engine Request #30625engine
  • T4 Civic Type R Brake Rotors #29817suspension & brakes
  • STL Solstice Ride Height #30183suspension & brakes
  • STL Request Mazda B5 DOHC #30420cars added
  • STL Honda B16A (JDM) Restrictor change #30531induction
  • T4 Mini Cooper Spec Line Anomalies #30478weight
  • T4 Request CAI Mustang in T4 #30562induction
  • STL ST Oil Coolers E&O Correction to 9.1.4.2.H #30388wording
  • T4 Request consistency review in GCR #30263other
  • STL GM Ecotec engines in STL #30247engine
  • STL Super Touring Alternate Miata Hubs #30345tyres & wheels
  • T4 E & O T4 Mustang Wheels #30245tyres & wheels
  • STL Brake Component Relocation #29990suspension & brakes
  • STL Super Touring Wing Clarification #30111aero
  • STL Transmission Options #30118other
  • 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
  • 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
  • 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
  • STL 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 20202020-10-022:31.420Danny Steyn · fastest of 33 · top 5 within 3.1s2:32.115Joe Moser · fastest of 30 · top 5 within 1.5s132.9Darin Treakle2:37.403John Heinricy · fastest of 20 · top 5 within 2.5s2:37.881Chi Ho · fastest of 19 · top 5 within 1.6s130.2Chi Ho+5.766squal +5.983s103.8%qual 104.0%
36 rule changes (STL: 11, T4: 25)5 weight · 4 cars added · 4 induction · 4 suspension & brakes · 3 engine · 3 tyres & wheels · 2 aero · 5 wording · 6 othershowhide
  • STL Minimum Weight Determination #27695weight
  • STL ST Gurney flap Wicker clarification #29012aero
  • T4 Scion FRS Solo Spec Coupe Gear Ratio #29021other
  • STL Request for Addition to GT3 Approved Turbo List #27576induction
  • 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
  • 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
  • T4 Request to Classify 2004 Mercedes Benz 320 CLK #27663cars added
  • STL STL Honda B18 restrictor changes #28794induction
  • T4 Request to change allowed header part # for T4 06-15 Miata #28223wording
  • T4 Z3M Roadster Weight #28437weight
  • 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
  • STL Request to add wheel part numbers #28342tyres & wheels
  • 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
  • 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
Virginia International Raceway Runoffs 20192019-10-052:07.203Danny Steyn · fastest of 36 · top 5 within 1.8s2:07.273Cliff Ira · fastest of 35 · top 5 within 1.4s134.8Cliff Ira1:55.124Bryce Cornet · fastest of 8 · top 5 within 2.3s2:15.816Bryce Cornet · fastest of 8 · top 5 within 4.9s135.7Bryce Cornet+8.543squal -12.079s106.7%qual 90.5%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+3.686squal +4.054s102.9%qual 103.2%1:54.469Pete Frost · only car1:57.688Pete Frost · only car145.9Pete Frost-9.585squal -12.734s92.5%qual 90.0%
26 rule changes (STL: 11, T4: 15)8 weight · 5 suspension & brakes · 3 cars added · 3 induction · 2 engine · 1 tyres & wheels · 3 wording · 1 othershowhide
  • STL Request to Classify Spec MX-5 Challenge in STL #27399cars added
  • T4 Request spare tire/wheel clarification #27012tyres & wheels
  • T4 Research E&O Mazda MX5 #27112weight
  • STL Request clarification for manifold and throttle in STU #27004induction
  • T4 MR2 Spyder Year Correction #26936wording
  • STL Request Restrictor Plate correction #26779induction
  • T4 Request to allow piggy back ECU on 2000 Mazda Protégé #26085engine
  • T4 Request helper spring as optional #26678suspension & brakes
  • STL Request Ride Height Clarification #26597suspension & brakes
  • T4 Request to classify 2000 - 2001 BMW 323 #25096cars added
  • 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
  • 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
  • T4 2012-2015 Honda Civic Si Performance Request #26129suspension & brakes
  • STL Request to equalize FPR Reduction on all B-Series Vtec Engines #24746weight
  • STL Request E&O for Mazda Miata Spec Line #25955weight
  • 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 20182018-10-101:49.138Danny Steyn · fastest of 19 · top 5 within 2.5s1:49.754Danny Steyn · fastest of 17 · top 5 within 2.5s103.2Craig McHaffie1:37.598Bryce Cornet · fastest of 13 · top 5 within 0.9s1:37.909Bryce Cornet · fastest of 12 · top 5 within 1.3s124.1Melvin David Kemper Jr-11.845squal -11.540s89.2%qual 89.4%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+4.276squal +3.201s103.9%qual 102.9%1:28.612J R Osborne · fastest of 7 · top 5 within 3.3s1:31.189J R Osborne · fastest of 7 · top 5 within 3.7s140.5J R Osborne-18.565squal -20.526s83.1%qual 81.2%
No rule changes on record between these events
Indianapolis Motor Speedway Runoffs 20172017-09-251:52.647Adam Roberts · fastest of 57 · top 5 within 0.8s1:52.589Eric Kutil · fastest of 50 · top 5 within 1.2s1:41.231Jarret Voorhies · fastest of 16 · top 5 within 1.7s1:41.146Jarret Voorhies · fastest of 16 · top 5 within 1.2s-11.443squal -11.416s89.8%qual 89.9%1:56.566Oscar Jackson · fastest of 40 · top 5 within 0.6s1:56.923Oscar Jackson · fastest of 38 · top 5 within 1.1s+4.334squal +3.919s103.8%qual 103.5%1:33.746Gary Hickman · fastest of 18 · top 5 within 3.3s1:33.702Alex Mayer · fastest of 17 · top 5 within 3.0s-18.887squal -18.901s83.2%qual 83.2%
No rule changes on record between these events
Mid-Ohio Sports Car Course Runoffs 20162016-09-191:35.439John Schmitt · fastest of 34 · top 5 within 1.5s1:36.625Kevin Boehm · fastest of 31 · top 5 within 0.6s1:26.043Jacob Loomis · fastest of 8 · top 5 within 3.1s1:27.922Jacob Loomis · fastest of 8 · top 5 within 2.7s-8.703squal -9.396s91.0%qual 90.2%1:38.813Jonathan Yanca · fastest of 34 · top 5 within 2.0s1:40.397Oscar Jackson · fastest of 32 · top 5 within 0.8s+3.772squal +3.374s103.9%qual 103.5%1:19.886Alex Mayer · fastest of 10 · top 5 within 1.5s1:21.015Jeremy Hill · fastest of 10 · top 5 within 1.2s-15.610squal -15.553s83.8%qual 83.7%
No rule changes on record between these events
Daytona International Speedway Runoffs 20152015-09-212:09.672Kevin Boehm · fastest of 37 · top 5 within 2.5s2:10.269Kevin Boehm · fastest of 37 · top 5 within 2.1s1:57.804Joseph Burton-Harris · fastest of 10 · top 5 within 2.3s1:58.029Joseph Burton-Harris · fastest of 10 · top 5 within 1.7s-12.240squal -11.868s90.6%qual 90.8%2:15.886Philip Royle · fastest of 22 · top 5 within 0.9s2:15.994Philip Royle · fastest of 20 · top 5 within 1.6s+5.725squal +6.214s104.4%qual 104.8%1:50.711J R Osborne · fastest of 20 · top 5 within 1.1s1:51.616J R Osborne · fastest of 19 · top 5 within 2.1s-18.653squal -18.961s85.7%qual 85.4%

By track

TrackEvents Typical % of STL 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 STL'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.