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BoP Lab / Classes / GTL

GTL vs SM vs SRF3 vs FF pace at every track

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

Class · click a class to switch, + to compare alongside (up to 4: remove one to add another)
Series
Reference class · the yardstick the % column and chart are measured against
Tracks · untick to narrow

Closest to the field: GTL 100.0% of GTL Jim Dentici, Daytona International Speedway Runoffs 2015 race · SM 98.5% of GTL Travis Wiley, Virginia International Raceway Runoffs 2022 race · SRF3 95.2% of GTL David Ogburn, Virginia International Raceway Runoffs 2023 race · FF 91.9% of GTL Jonathan Kotyk, Virginia International Raceway Runoffs 2023 race

1:402:002:202:4023 rule changes between Runoffs 2018 and Runoffs 201923 ▾30 rule changes between Runoffs 2019 and Runoffs 202030 ▾18 rule changes between Runoffs 2020 and Runoffs 202118 ▾7 rule changes between Runoffs 2021 and Runoffs 20227 ▾13 rule changes between Runoffs 2022 and Runoffs 202313 ▾32 rule changes between Runoffs 2023 and Runoffs 202432 ▾14 rule changes between Runoffs 2024 and Runoffs 202514 ▾7 rule changes between Runoffs 2025 and Runoffs 20267 ▾GTL race best at Runoffs 2015: 2:13.564 (Jim Dentici)GTL race best at Runoffs 2016: 1:35.912 (Kyle Disque)GTL race best at Runoffs 2017: 1:52.068 (Christopher Bovis)GTL race best at Runoffs 2018: 1:49.458 (Troy Ermish)GTL race best at Runoffs 2019: 2:07.837 (Bill Ball)GTL race best at Runoffs 2020: 2:31.601 (Peter Shadowen)GTL race best at Runoffs 2021: 1:51.952 (Scott Twomey)GTL race best at Runoffs 2022: 2:21.180 (Michael Lewis)GTL race best at Runoffs 2023: 2:11.277 (Graham Fuller)GTL race best at Runoffs 2024: 2:30.844 (Chris Bovis)GTL qualifying best at Runoffs 2015: 2:11.387 (Jim Dentici)GTL qualifying best at Runoffs 2016: 1:35.377 (Wilson Wright)GTL qualifying best at Runoffs 2017: 1:50.331 (Christopher Bovis)GTL qualifying best at Runoffs 2018: 1:47.885 (Troy Ermish)GTL qualifying best at Runoffs 2019: 2:06.997 (Peter Shadowen)GTL qualifying best at Runoffs 2020: 2:31.943 (Chris Bovis)GTL qualifying best at Runoffs 2021: 1:51.819 (Christopher Bovis)GTL qualifying best at Runoffs 2022: 2:07.789 (Peter Shadowen)GTL qualifying best at Runoffs 2023: 2:09.564 (Peter Shadowen)GTL qualifying best at Runoffs 2024: 2:30.858 (Peter Shadowen)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)SRF3 race best at Runoffs 2015: 2:10.215 (Chad Galloway)SRF3 race best at Runoffs 2016: 1:34.947 (Cliff White)SRF3 race best at Runoffs 2017: 1:49.782 (Tray Ayres)SRF3 race best at Runoffs 2018: 1:47.053 (TJ Acker)SRF3 race best at Runoffs 2019: 2:04.755 (Bobby Sak)SRF3 race best at Runoffs 2020: 2:31.038 (Justin Hille)SRF3 race best at Runoffs 2021: 1:50.095 (John Black)SRF3 race best at Runoffs 2022: 2:22.066 (Franklin Futrelle)SRF3 race best at Runoffs 2023: 2:04.911 (David Ogburn)SRF3 race best at Runoffs 2024: 2:28.129 (S Sandy Satullo III)SRF3 race best at Runoffs 2025: 2:29.839 (Morgan Burkhard)SRF3 race best at Runoffs 2026: 2:29.257 (Peyton Long)SRF3 qualifying best at Runoffs 2015: 2:08.557 (Kerry Jacobsen)SRF3 qualifying best at Runoffs 2016: 1:34.363 (John Black)SRF3 qualifying best at Runoffs 2017: 1:49.824 (John Black)SRF3 qualifying best at Runoffs 2018: 1:46.117 (Robeson Clay Russell)SRF3 qualifying best at Runoffs 2019: 2:04.624 (Brian Schofield)SRF3 qualifying best at Runoffs 2020: 2:29.786 (TJ Acker)SRF3 qualifying best at Runoffs 2021: 1:49.520 (Franklin Futrelle)SRF3 qualifying best at Runoffs 2022: 2:03.716 (Franklin Futrelle)SRF3 qualifying best at Runoffs 2023: 2:03.842 (Morgan Burkhard)SRF3 qualifying best at Runoffs 2024: 2:27.773 (Denny Stripling)SRF3 qualifying best at Runoffs 2025: 2:28.226 (Bobby Sak)SRF3 qualifying best at Runoffs 2026: 2:27.443 (Tyler Stephens)FF race best at Runoffs 2015: 2:03.383 (Rick Payne)FF race best at Runoffs 2016: 1:30.133 (Neil Verhagen)FF race best at Runoffs 2017: 1:44.524 (Jonathon Kotyk)FF race best at Runoffs 2018: 1:42.049 (Jonathon Kotyk)FF race best at Runoffs 2019: 2:20.474 (Jonathan Kotyk)FF race best at Runoffs 2020: 2:24.268 (Jeffrey Bartz)FF race best at Runoffs 2021: 1:55.676 (Jonathan Kotyk)FF race best at Runoffs 2022: 2:18.358 (Jonathan Kotyk)FF race best at Runoffs 2023: 2:00.583 (Jonathan Kotyk)FF race best at Runoffs 2024: 2:22.057 (Sebastian Mateo Naranjo)FF race best at Runoffs 2025: 2:25.541 (Calvin Kautz)FF race best at Runoffs 2026: 2:23.686 (Nathan Down)FF qualifying best at Runoffs 2015: 2:02.489 (Tim Kautz)FF qualifying best at Runoffs 2016: 1:29.213 (Neil Verhagen)FF qualifying best at Runoffs 2017: 1:44.601 (Zach Holden)FF qualifying best at Runoffs 2018: 1:41.612 (Jonathon Kotyk)FF qualifying best at Runoffs 2019: 1:59.563 (Tyler O'Connor)FF qualifying best at Runoffs 2020: 2:22.916 (Simon Sikes)FF qualifying best at Runoffs 2021: 1:44.359 (Jonathan Kotyk)FF qualifying best at Runoffs 2022: 1:59.215 (Jonathan Kotyk)FF qualifying best at Runoffs 2023: 1:59.249 (Nolan Allaer)FF qualifying best at Runoffs 2024: 2:22.552 (Calvin Kautz)FF qualifying best at Runoffs 2025: 2:24.905 (Jonathan Kotyk)FF qualifying best at Runoffs 2026: 2:23.047 (David Ybarra)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
GTLSMSRF3FFsolid race · dashed qualifying · slower is lower
95%100%105%23 rule changes between Runoffs 2018 and Runoffs 201923 ▾30 rule changes between Runoffs 2019 and Runoffs 202030 ▾18 rule changes between Runoffs 2020 and Runoffs 202118 ▾7 rule changes between Runoffs 2021 and Runoffs 20227 ▾13 rule changes between Runoffs 2022 and Runoffs 202313 ▾32 rule changes between Runoffs 2023 and Runoffs 202432 ▾14 rule changes between Runoffs 2024 and Runoffs 202514 ▾7 rule changes between Runoffs 2025 and Runoffs 20267 ▾GTL race best at Runoffs 2015: 100.0% of GTL's (Jim Dentici)GTL race best at Runoffs 2016: 100.0% of GTL's (Kyle Disque)GTL race best at Runoffs 2017: 100.0% of GTL's (Christopher Bovis)GTL race best at Runoffs 2018: 100.0% of GTL's (Troy Ermish)GTL race best at Runoffs 2019: 100.0% of GTL's (Bill Ball)GTL race best at Runoffs 2020: 100.0% of GTL's (Peter Shadowen)GTL race best at Runoffs 2021: 100.0% of GTL's (Scott Twomey)GTL race best at Runoffs 2022: 100.0% of GTL's (Michael Lewis)GTL race best at Runoffs 2023: 100.0% of GTL's (Graham Fuller)GTL race best at Runoffs 2024: 100.0% of GTL's (Chris Bovis)GTL qualifying best at Runoffs 2015: 100.0% of GTL's (Jim Dentici)GTL qualifying best at Runoffs 2016: 100.0% of GTL's (Wilson Wright)GTL qualifying best at Runoffs 2017: 100.0% of GTL's (Christopher Bovis)GTL qualifying best at Runoffs 2018: 100.0% of GTL's (Troy Ermish)GTL qualifying best at Runoffs 2019: 100.0% of GTL's (Peter Shadowen)GTL qualifying best at Runoffs 2020: 100.0% of GTL's (Chris Bovis)GTL qualifying best at Runoffs 2021: 100.0% of GTL's (Christopher Bovis)GTL qualifying best at Runoffs 2022: 100.0% of GTL's (Peter Shadowen)GTL qualifying best at Runoffs 2023: 100.0% of GTL's (Peter Shadowen)GTL qualifying best at Runoffs 2024: 100.0% of GTL's (Peter Shadowen)SM race best at Runoffs 2015: 107.9% of GTL's (Todd Lamb)SM race best at Runoffs 2016: 105.1% of GTL's (Michael Carter)SM race best at Runoffs 2017: 106.3% of GTL's (Michael Gagliardo)SM race best at Runoffs 2018: 105.3% of GTL's (Michael Carter)SM race best at Runoffs 2019: 106.7% of GTL's (Elivan Goulart)SM race best at Runoffs 2020: 108.0% of GTL's (Preston Pardus)SM race best at Runoffs 2021: 106.1% of GTL's (Brian Henderson)SM race best at Runoffs 2022: 98.5% of GTL's (Travis Wiley)SM race best at Runoffs 2023: 103.8% of GTL's (Julian DaCosta)SM race best at Runoffs 2024: 107.1% of GTL's (Brett Kowalski)SM qualifying best at Runoffs 2015: 105.5% of GTL's (Andrew Carbonell)SM qualifying best at Runoffs 2016: 105.4% of GTL's (Justin Hille)SM qualifying best at Runoffs 2017: 107.2% of GTL's (Chris Haldeman)SM qualifying best at Runoffs 2018: 106.0% of GTL's (Ken Sutherland)SM qualifying best at Runoffs 2019: 105.9% of GTL's (Todd Buras)SM qualifying best at Runoffs 2020: 106.8% of GTL's (Kyle Greenhill)SM qualifying best at Runoffs 2021: 105.3% of GTL's (Brian Henderson)SM qualifying best at Runoffs 2022: 105.4% of GTL's (Danny Steyn)SM qualifying best at Runoffs 2023: 104.2% of GTL's (Danny Steyn)SM qualifying best at Runoffs 2024: 106.8% of GTL's (Ethan Goulart)SRF3 race best at Runoffs 2015: 97.5% of GTL's (Chad Galloway)SRF3 race best at Runoffs 2016: 99.0% of GTL's (Cliff White)SRF3 race best at Runoffs 2017: 98.0% of GTL's (Tray Ayres)SRF3 race best at Runoffs 2018: 97.8% of GTL's (TJ Acker)SRF3 race best at Runoffs 2019: 97.6% of GTL's (Bobby Sak)SRF3 race best at Runoffs 2020: 99.6% of GTL's (Justin Hille)SRF3 race best at Runoffs 2021: 98.3% of GTL's (John Black)SRF3 race best at Runoffs 2022: 100.6% of GTL's (Franklin Futrelle)SRF3 race best at Runoffs 2023: 95.2% of GTL's (David Ogburn)SRF3 race best at Runoffs 2024: 98.2% of GTL's (S Sandy Satullo III)SRF3 qualifying best at Runoffs 2015: 97.8% of GTL's (Kerry Jacobsen)SRF3 qualifying best at Runoffs 2016: 98.9% of GTL's (John Black)SRF3 qualifying best at Runoffs 2017: 99.5% of GTL's (John Black)SRF3 qualifying best at Runoffs 2018: 98.4% of GTL's (Robeson Clay Russell)SRF3 qualifying best at Runoffs 2019: 98.1% of GTL's (Brian Schofield)SRF3 qualifying best at Runoffs 2020: 98.6% of GTL's (TJ Acker)SRF3 qualifying best at Runoffs 2021: 97.9% of GTL's (Franklin Futrelle)SRF3 qualifying best at Runoffs 2022: 96.8% of GTL's (Franklin Futrelle)SRF3 qualifying best at Runoffs 2023: 95.6% of GTL's (Morgan Burkhard)SRF3 qualifying best at Runoffs 2024: 98.0% of GTL's (Denny Stripling)FF race best at Runoffs 2015: 92.4% of GTL's (Rick Payne)FF race best at Runoffs 2016: 94.0% of GTL's (Neil Verhagen)FF race best at Runoffs 2017: 93.3% of GTL's (Jonathon Kotyk)FF race best at Runoffs 2018: 93.2% of GTL's (Jonathon Kotyk)Off the chart: FF race best at Runoffs 2019: 109.9% of GTL's (Jonathan Kotyk)FF race best at Runoffs 2020: 95.2% of GTL's (Jeffrey Bartz)FF race best at Runoffs 2021: 103.3% of GTL's (Jonathan Kotyk)FF race best at Runoffs 2022: 98.0% of GTL's (Jonathan Kotyk)FF race best at Runoffs 2023: 91.9% of GTL's (Jonathan Kotyk)FF race best at Runoffs 2024: 94.2% of GTL's (Sebastian Mateo Naranjo)FF qualifying best at Runoffs 2015: 93.2% of GTL's (Tim Kautz)FF qualifying best at Runoffs 2016: 93.5% of GTL's (Neil Verhagen)FF qualifying best at Runoffs 2017: 94.8% of GTL's (Zach Holden)FF qualifying best at Runoffs 2018: 94.2% of GTL's (Jonathon Kotyk)FF qualifying best at Runoffs 2019: 94.1% of GTL's (Tyler O'Connor)FF qualifying best at Runoffs 2020: 94.1% of GTL's (Simon Sikes)FF qualifying best at Runoffs 2021: 93.3% of GTL's (Jonathan Kotyk)FF qualifying best at Runoffs 2022: 93.3% of GTL's (Jonathan Kotyk)FF qualifying best at Runoffs 2023: 92.0% of GTL's (Nolan Allaer)FF qualifying best at Runoffs 2024: 94.5% of GTL's (Calvin Kautz)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
GTLSMSRF3FFsolid race · dashed qualifying · each class's best lap as a share of GTL's at the same event (the reference class, changeable above); 100% is level, less is quicker, so up the chart is quicker
EventGTLSMSRF3FF
Qual best Race best Trap Qual best Race best Trap vs GTL % of GTL Qual best Race best Trap vs GTL % of GTL Qual best Race best Trap vs GTL % of GTL 
Road America Runoffs 20262026-09-282:42.173Brett 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%)2:27.443Tyler Stephens · fastest of 44 · top 5 within 0.3s-0.783s (-0.53%)2:29.257Peyton Long · fastest of 42 · top 5 within 0.3s-0.582s (-0.39%)134.1Bobby Sak+0.4 mph (+0.3%)2:23.047David Ybarra · fastest of 20 · top 5 within 1.4s-1.858s (-1.28%)2:23.686Nathan Down · fastest of 20 · top 5 within 1.6s-1.855s (-1.27%)138.9Tazio Stefanelli+0.5 mph (+0.3%)
7 rule changes (GTL: 1, SM: 2, SRF3: 2, FF: 2)2 engine · 1 cars added · 1 tyres & wheels · 2 wording · 1 other · FF Kent 1600 compression ratio calculation parameters reorganized: bore size and valve protrusion limits moved to separate subsections for clarity. · SM/SMX Mazda rear toe link part number revised from 0000-04-5361426 to 0000-04-5361. · SM/SMX part number 0000-10-6900 replaced with 0000-06-5016-KT in GCR 9.1.7.C.1.j.1.c. · GT3U class removed from GCR; GT3U cars now compete in STU. · SRF3 spark plugs limited to NGK LTR7IX-11 P/N G301041 only; washers and sealing rings prohibited. · FF clarifies alternative tire eligibility: homologated 1989 or earlier with rocker or outboard suspension all four corners; push-rod/pull-rod cars may seek approval. · SRF3 adds HD Oil Cooler P/N G1148500 option alongside standard P/N G480503, no fan permitted.showhide
  • FF Clarification in FF Kent 1600 Compression Ratio Paragraph #40293wordingwordingFF Kent 1600 compression ratio calculation parameters reorganized: bore size and valve protrusion limits moved to separate subsections for clarity.
  • SM Rear Toe Link #40271wordingwordingSM/SMX Mazda rear toe link part number revised from 0000-04-5361426 to 0000-04-5361.
  • SM Part Number Change Request #39914otherunclearSM/SMX part number 0000-10-6900 replaced with 0000-06-5016-KT in GCR 9.1.7.C.1.j.1.c.
  • GTL Remove GT3U from GCR as it is now in STU #39862cars addedremovedcars addedGT3U class removed from GCR; GT3U cars now compete in STU.
  • SRF3 SRF3 Spark Plugs #39899engineengineSRF3 spark plugs limited to NGK LTR7IX-11 P/N G301041 only; washers and sealing rings prohibited.
  • FF Formula F Alternative Tire Rule Proposed Clarifications #39281tyres & wheelsaddedtyres & wheelsFF clarifies alternative tire eligibility: homologated 1989 or earlier with rocker or outboard suspension all four corners; push-rod/pull-rod cars may seek approval.
  • SRF3 Add HD Oil Cooler #38979engineaddedengineSRF3 adds HD Oil Cooler P/N G1148500 option alongside standard P/N G480503, no fan permitted.
Road America Runoffs 20252025-09-292:43.111Bobby 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%)2:28.226Bobby Sak · fastest of 43 · top 5 within 0.6s+0.453s (+0.31%)2:29.839Morgan Burkhard · fastest of 42 · top 5 within 0.3s+1.710s (+1.15%)133.7Bobby Sak-1.5 mph (-1.1%)2:24.905Jonathan Kotyk · fastest of 17 · top 5 within 1.1s+2.353s (+1.65%)2:25.541Calvin Kautz · fastest of 16 · top 5 within 0.5s+3.484s (+2.45%)138.4Tazio Stefanelli-2.3 mph (-1.6%)
14 rule changes (GTL: 3, SM: 4, SRF3: 3, FF: 4)3 engine · 2 tyres & wheels · 1 weight · 5 wording · 3 other · SRF3 adds oil cooler options P/N G480503 and P/N G1148500; brake rule restructured to list Hawk Blue pads, Wilwood rotor, caliper kit, master cylinder options. · SMX drivers must submit data acquisition files on time or face suspension and $250 fine. · SMX penalty language clarified: level 1 and 3 infractions may carry $1,000 fines, level 2 and 4 may carry $500 fines. · FF adds rocker arm and outboard suspension cars option to use Hoosier bias ply slicks or VFF tyres; clarifies mixing rules. · SM tire marking rules clarified: one Hoosier SM 7.5 P205/50/ZR17 set per Super Tour weekend, impound after first dry session, damaged tires may be replaced with used tires only. · SRF drivers with disabilities may modify seat and controls for safety and comfort with SCCA approval, noted in logbook, for that driver only. · SRF SADEV-SRF3 6-speed sequential transmission: effective date clarified to 1 April 2025 onward. · FF adds alternative tire options for older cars with rocker arm or outboard suspension: bias ply slicks or VFF radials. · TA2 rear wing height rule clarified: OEM aerodynamic devices exempt from peak-of-roof height limit. · SMX OE instrument cluster must stay unmodified and connected; aftermarket dash allowed if wiring only re-routed; alternate gauges now permitted; foot pedal comfort mods allowed without relocation. · FF and FC sequential gearbox weight penalty reduces from 25 lbs to 10 lbs minimum weight addition. · FF Honda Fit pistons: OEM 0.25mm oversize PN 13020-RB7-Z00 or Fast Forward PN FF800-110 now both allowed; standard diameter 73.240mm (2.8835 inches), minimum weight 198.0g. · GTL Toyota G16E-GTS removes direct injection prohibition, allowing direct injection engines. · GTL L16 limited prep gains 32mm choke option at 1910 lbs, compression capped 12.0:1, valve lift .450 max.showhide
  • SRF3 SRF Rule Updates #38853otheraddedSRF3 adds oil cooler options P/N G480503 and P/N G1148500; brake rule restructured to list Hawk Blue pads, Wilwood rotor, caliper kit, master cylinder options.
  • SM SMX Data Submission - Penalties #38248otheraddedSMX drivers must submit data acquisition files on time or face suspension and $250 fine.
  • SM Committee) SMX Penaly Clarification updated language #38337wordingwordingSMX penalty language clarified: level 1 and 3 infractions may carry $1,000 fines, level 2 and 4 may carry $500 fines.
  • FF Page 228, FF tire rule 9.1.1.10.e #38251tyres & wheelsaddedtyres & wheelsFF adds rocker arm and outboard suspension cars option to use Hoosier bias ply slicks or VFF tyres; clarifies mixing rules.
  • SM Clarify Tire Marking Regs #38005wordingwordingSM tire marking rules clarified: one Hoosier SM 7.5 P205/50/ZR17 set per Super Tour weekend, impound after first dry session, damaged tires may be replaced with used tires only.
  • SRF3 Driver Safety & Comfort #37966otheraddedSRF drivers with disabilities may modify seat and controls for safety and comfort with SCCA approval, noted in logbook, for that driver only.
  • SRF3 Update SADEV transmission specs #37992wordingwordingSRF SADEV-SRF3 6-speed sequential transmission: effective date clarified to 1 April 2025 onward.
  • FF Formula F Proposal to Invite Older Cars Via a Tire Rule Change #37802tyres & wheelsaddedtyres & wheelsFF adds alternative tire options for older cars with rocker arm or outboard suspension: bias ply slicks or VFF radials.
  • GTL Correct language regarding OEM Areo Devices #37137wordingwordingTA2 rear wing height rule clarified: OEM aerodynamic devices exempt from peak-of-roof height limit.
  • SM E&O SMX Regs 9.1.7.1.D.5.u-.w #37070wordingwordingSMX OE instrument cluster must stay unmodified and connected; aftermarket dash allowed if wiring only re-routed; alternate gauges now permitted; foot pedal comfort mods allowed without relocation.
  • FF Change FF/FC Weight with Sequential Gearbox #36651weightfasterweightFF and FC sequential gearbox weight penalty reduces from 25 lbs to 10 lbs minimum weight addition.
  • FF Alternative Oversize Honda Fit Pistons #37064engineaddedengineFF Honda Fit pistons: OEM 0.25mm oversize PN 13020-RB7-Z00 or Fast Forward PN FF800-110 now both allowed; standard diameter 73.240mm (2.8835 inches), minimum weight 198.0g.
  • GTL G16E-GTS Fuel Injection Spec Line Change #36588engineaddedengineGTL Toyota G16E-GTS removes direct injection prohibition, allowing direct injection engines.
  • GTL GTL Alternate Weight and Choke Option for L16 engine #36653engineaddedengineGTL L16 limited prep gains 32mm choke option at 1910 lbs, compression capped 12.0:1, valve lift .450 max.
Road America Runoffs 20242024-10-012:30.858Peter Shadowen · fastest of 14 · top 5 within 4.4s-1.085s (-0.71%)2:30.844Chris Bovis · fastest of 13 · top 5 within 3.7s-0.757s (-0.50%)133.3Peter Shadowen+1.8 mph (+1.4%)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%)+10.642squal +10.248s107.1%qual 106.8%2:27.773Denny Stripling · fastest of 57 · top 5 within 0.3s-2.013s (-1.34%)2:28.129S Sandy Satullo III · fastest of 52 · top 5 within 0.7s-2.909s (-1.93%)135.2Denny Stripling+3.4 mph (+2.6%)-2.715squal -3.085s98.2%qual 98.0%2:22.552Calvin Kautz · fastest of 13 · top 5 within 1.1s-0.364s (-0.25%)2:22.057Sebastian Mateo Naranjo · fastest of 13 · top 5 within 0.6s-2.211s (-1.53%)140.7Calvin Kautz+2.6 mph (+1.9%)-8.787squal -8.306s94.2%qual 94.5%
32 rule changes (GTL: 16, SM: 4, SRF3: 10, FF: 2)5 cars added · 5 engine · 4 weight · 2 suspension & brakes · 1 aero · 1 induction · 1 tyres & wheels · 8 wording · 5 other · FF EGR blanking plate rule clarified: VTEC activation valve must be retained and functioning, no modifications permitted. · SRF3 air filter rule removes K&N RC-9160 option, specifies Weems P/N WM301020 only. · SRF Wilwood vented rotor minimum thickness increases to 13.25mm, 0.522 inches. · SRF3 Hoosier decal placement changed from four logos on nose and tail to three logos on sides and center front. · GTL adds Toyota GR86 2021–2023, 2dr RWD, 101.3 in wheelbase. · GTL adds Spec Miata 1990–2005 with legal Spec Miata engine and intake system. · GTL adds Mazda MX5 RF 2017- model with 91.0 in wheelbase. · SMX Spec MX-5 camera requirement: non-functioning recorder now will instead of may warrant penalty or disqualification. · SM and SMX must run latest AIM Data Logger Spec MX-5 ECU Protocol, effective 2024-09-01. · SMX Mazda MX-5 OE versus OEM definitions clarified in GCR section 9.1.7.1; wording change only. · SM and SMX now allow an alternate shifter bushing at the bottom of the shift lever. · SRF Hoosier contingency decal requirement reduced from four decals in specific locations to three decals with simplified placement. · SRF wet tyres: front P185/60R13 H20 or W2 and rear P205/60R13 H20 or W2 removed; front P185/65R13 W2 and rear P205/60R13 W2 now required. Hoosier decal placement specified. · GTL added to GT3 choke option line in GCR 9.1.2.E.13.n. · SRF3 alternator pulley minimum weight drops from 12 to 11 oz, adds P/N G902131 six-row option. · GT2-ST Acura NSX minimum weight rises to 3000 lbs, restrictor increases to 45mm TIR. · GTL Datsun 510 Limited Prep fuel induction increased to 34 mm chokes, minimum weight rises to 2000 lbs. · GT1-GTX rear blade spoiler: angle 50–75°, max 59.0 wide by 5.0 high inches; total area limit removed. · GT1, GT2, GT3, GTL, GTX Direct Injection now permitted if original equipment. · GT2 Nissan and GT3 Mazda, Mitsubishi 4G93, Nissan QR25DE/DD, QE25DE/DD now permit Direct Injection per 9.1.2.F.7.5.E. · FF Honda Fit gains Fast Forward oversize piston ring option PN FF800-100 as alternative to Riken or Nippon. · GTL 12A rotary engines may machine and use 13B housing to O.E. 12A spec across all port types. · GTL Toyota DR86 2021–2024 added to class. · GTL BMW Mini model years changed to 2002-2013. · SRF rain/brake light must be Super Bright LEDs Inc. P/N PT-STRB-R24; secondary filament must connect to rain light switch. · SRF brake light must be Super Bright LEDs Inc. P/N PT-STRB-R24, with SCCA Enterprises P/N 180427A pigtail and strobing rain light kit. · SRF adds mandatory front brake ducts 12–36 inches, throttle pedal heel-toe extension, braided stainless flex lines, camber limit 5.0 degrees, radiator opening height 3½ ± ½ inches, rear shift cable clamp P/N WM302007A. · GTL small unrestricted engines under 1399cc lose 38–79 lbs across Alfa, AMC, Triumph, Mini, Sprite, Fiat, Ford, Honda, Mazda, Nissan, Subaru, Toyota, Volkswagen. · GTL Honda Fit 2009-13 2-door FWD added with 99.0 in wheelbase, alternate 94.0 and 97.0 in. · GTL spec lines moved contiguous with GT2 and GT3; GTA category and specs renumbered behind GTL; P2 engine tables reorganised with restrictor and weight specifications clarified. · GTL Nissan Sentra/200SX A 1400 minimum weight reduced to 1800 lbs. · SRF radiator options expanded: Enterprises P/N 480465 with baffle 480464, 480466, or Automotive 1R698 and CU698 allowed if cross-reference equivalent.showhide
  • FF Update to FF EGR Blanking Plate Rule #36633wordingwordingFF EGR blanking plate rule clarified: VTEC activation valve must be retained and functioning, no modifications permitted.
  • SRF3 Update SRF3 Air Filter Rule #36681wordingremovedSRF3 air filter rule removes K&N RC-9160 option, specifies Weems P/N WM301020 only.
  • SRF3 Update SRF Brake Rotor Thickness #36687suspension & brakessuspension & brakesSRF Wilwood vented rotor minimum thickness increases to 13.25mm, 0.522 inches.
  • SRF3 Hoosier Tire Decal Placement #36739wordingwordingSRF3 Hoosier decal placement changed from four logos on nose and tail to three logos on sides and center front.
  • GTL Request to Include Toyota GR86 in GTL #36324cars addedaddedGTL adds Toyota GR86 2021–2023, 2dr RWD, 101.3 in wheelbase.
  • GTL Inclusion of Modified Spec Miata for GTL competition #36325cars addedaddedGTL adds Spec Miata 1990–2005 with legal Spec Miata engine and intake system.
  • GTL Include Mazda MX5 RF 2017- in GTL #36428cars addedaddedGTL adds Mazda MX5 RF 2017- model with 91.0 in wheelbase.
  • SM SMX Camera Rule Correction #36496wordingwordingSMX Spec MX-5 camera requirement: non-functioning recorder now will instead of may warrant penalty or disqualification.
  • SM Committee) AIM ECU Protocol #36556engineaddedengineSM and SMX must run latest AIM Data Logger Spec MX-5 ECU Protocol, effective 2024-09-01.
  • SM Committee) OE versus OEM Definitons #36608wordingwordingSMX Mazda MX-5 OE versus OEM definitions clarified in GCR section 9.1.7.1; wording change only.
  • SM Committee) Shifter Bushing #36611otheraddedSM and SMX now allow an alternate shifter bushing at the bottom of the shift lever.
  • SRF3 Update to Letter 36619 with new Hoosier Contingency Decal Info #36624wordingwordingSRF Hoosier contingency decal requirement reduced from four decals in specific locations to three decals with simplified placement.
  • SRF3 Update Rain Tire Rule and Hoosier Decal Placement #36436tyres & wheelstyres & wheelsSRF wet tyres: front P185/60R13 H20 or W2 and rear P205/60R13 H20 or W2 removed; front P185/65R13 W2 and rear P205/60R13 W2 now required. Hoosier decal placement specified.
  • GTL Add GTL to GT3 choke option line. #36236otheraddedGTL added to GT3 choke option line in GCR 9.1.2.E.13.n.
  • SRF3 SRF3 Alternator Pulley Update In #36095weightfasterweightSRF3 alternator pulley minimum weight drops from 12 to 11 oz, adds P/N G902131 six-row option.
  • GTL Request for Spec Line 1010 Reconsideration #35009weight +300 lbsslowerweightGT2-ST Acura NSX minimum weight rises to 3000 lbs, restrictor increases to 45mm TIR.
  • GTL Allow 34 mm chokes for the Datsun 510 #35661induction +50 lbsfasterinductionGTL Datsun 510 Limited Prep fuel induction increased to 34 mm chokes, minimum weight rises to 2000 lbs.
  • GTL Rear Blade Spoiler Clarification #35261aeroaeroGT1-GTX rear blade spoiler: angle 50–75°, max 59.0 wide by 5.0 high inches; total area limit removed.
  • GTL GT Direct Injection allowance and rules #35437engineaddedengineGT1, GT2, GT3, GTL, GTX Direct Injection now permitted if original equipment.
  • GTL GT2/3 remove Direction Injection not allowed in Spec line notes #35439engineaddedengineGT2 Nissan and GT3 Mazda, Mitsubishi 4G93, Nissan QR25DE/DD, QE25DE/DD now permit Direct Injection per 9.1.2.F.7.5.E.
  • FF Honda Fit Oversize Piston Rings #35305engineaddedengineFF Honda Fit gains Fast Forward oversize piston ring option PN FF800-100 as alternative to Riken or Nippon.
  • GTL Rotary Engine 12A Rotor Housings #35131engineaddedengineGTL 12A rotary engines may machine and use 13B housing to O.E. 12A spec across all port types.
  • GTL Request to Include Toyota GR86 in GTL #35198cars addedaddedGTL Toyota DR86 2021–2024 added to class.
  • GTL Errors and Omissions, GTL engines & Cars #35226wordingwordingGTL BMW Mini model years changed to 2002-2013.
  • SRF3 Update SRF Rain / Brake Rule #34706otherotherSRF rain/brake light must be Super Bright LEDs Inc. P/N PT-STRB-R24; secondary filament must connect to rain light switch.
  • SRF3 Update SRF Brake Light Rule v1 #34853otherotherSRF brake light must be Super Bright LEDs Inc. P/N PT-STRB-R24, with SCCA Enterprises P/N 180427A pigtail and strobing rain light kit.
  • SRF3 SRF / SRF3 Rule Updates #35268suspension & brakessuspension & brakesSRF adds mandatory front brake ducts 12–36 inches, throttle pedal heel-toe extension, braided stainless flex lines, camber limit 5.0 degrees, radiator opening height 3½ ± ½ inches, rear shift cable clamp P/N WM302007A.
  • GTL Small Engines in GT Lite #34842weightfasterweightGTL small unrestricted engines under 1399cc lose 38–79 lbs across Alfa, AMC, Triumph, Mini, Sprite, Fiat, Ford, Honda, Mazda, Nissan, Subaru, Toyota, Volkswagen.
  • GTL Request to Classify Honda Fit body in GTL #35020cars addedaddedGTL Honda Fit 2009-13 2-door FWD added with 99.0 in wheelbase, alternate 94.0 and 97.0 in.
  • GTL Errors in GTCS Headings and Use of the Terms Category and ClassChange existing GTL and GTA Rules #34453wordingwordingGTL spec lines moved contiguous with GT2 and GT3; GTA category and specs renumbered behind GTL; P2 engine tables reorganised with restrictor and weight specifications clarified.
  • GTL Weight for Nissan Sentra/200SX A 1400's #34918weight -50 lbsfasterweightGTL Nissan Sentra/200SX A 1400 minimum weight reduced to 1800 lbs.
  • SRF3 SRF Radiator Rule Update #34805otheraddedSRF radiator options expanded: Enterprises P/N 480465 with baffle 480464, 480466, or Automotive 1R698 and CU698 allowed if cross-reference equivalent.
Virginia International Raceway Runoffs 20232023-09-232:09.564Peter Shadowen · fastest of 11 · top 5 within 4.9s+1.775s (+1.39%)2:11.277Graham Fuller · fastest of 10 · top 5 within 2.4s-9.903s (-7.01%)142.7Peter Shadowen+6.7 mph (+4.9%)2:14.986Danny Steyn · fastest of 52 · top 5 within 0.1s+0.322s (+0.24%)2:16.229Julian DaCosta · fastest of 46 · top 5 within 0.3s-2.878s (-2.07%)120.3Jim Drago+1.1 mph (+0.9%)+4.952squal +5.422s103.8%qual 104.2%2:03.842Morgan Burkhard · fastest of 40 · top 5 within 0.2s+0.126s (+0.10%)2:04.911David Ogburn · fastest of 39 · top 5 within 0.3s-17.155s (-12.08%)134.5Bobby Sak+0.1 mph (+0.0%)-6.366squal -5.722s95.2%qual 95.6%1:59.249Nolan Allaer · fastest of 8 · top 5 within 2.8s+0.034s (+0.03%)2:00.583Jonathan Kotyk · fastest of 8 · top 5 within 0.4s-17.775s (-12.85%)138.4Calvin Kautz+0.1 mph (+0.1%)-10.694squal -10.315s91.9%qual 92.0%
13 rule changes (GTL: 7, SM: 1, SRF3: 4, FF: 1)4 cars added · 3 engine · 2 tyres & wheels · 2 weight · 2 wording · SRF wet front tyre changes to Hoosier P/N 46100 P185/60R13 H20 or W2 with 2.5" ground clearance. · Fields Cardinal V8 added to GT1 with Ford V8 engine, 4.9L, 2100 lbs, fuel injection. · SRF front W2 rain tyre Hoosier part number changes from 46100 to 46101 P185/65R13. · FF Honda Fit engine adds Fast Forward part number alternatives for intake, exhaust, oil system, and scavenge pump components. · SRF removes 1985 Renault Alliance solid front rotor option; restrictor sizes decrease 1mm for newer Kawasaki and multi-brand engines; minimum weights increase to 1100 lbs. · SRF3 alternate dash panel P/N 180100 or 180101 moved from optional to required bodywork section. · GTL 3K, 4K, 5K Toyota engines may now use 4Y block only. · GT2 and GTL add Toyota 4A-F and 4A-FE 1.6L DOHC 16V engines as permitted options. · SM Mazda MX-5 Miata 01-05 minimum weight rises to 2450 lbs, or 2465 with alternate bore. · GTL Fiat X1/9 1500 Limited Prep minimum weight increases to 2000 lbs from 1835 lbs. · GT2 TA2 and GTA throttle body part numbers updated to GM 12570790 or Edelbrock 33869/3870. · GTL adds Ford Festiva 1988-1993 FWD hatchback with Mazda B3 1324cc engine. · GTL adds Toyota G16E-GTS 1618cc DOHC 3-cyl engine, 1945 lbs, SIR, no turbo or direct injection.showhide
  • SRF3 Hoosier SRF Wet Front Tire Rule Update #34189tyres & wheelstyres & wheelsSRF wet front tyre changes to Hoosier P/N 46100 P185/60R13 H20 or W2 with 2.5" ground clearance.
  • GTL Please classify Fields Cardinal V8 #33784cars addedaddedFields Cardinal V8 added to GT1 with Ford V8 engine, 4.9L, 2100 lbs, fuel injection.
  • SRF3 Update SRF Front W2 Rain Tire Part Number #34118tyres & wheelstyres & wheelsSRF front W2 rain tyre Hoosier part number changes from 46100 to 46101 P185/65R13.
  • FF Add Fast Forward Part Numbers for Honda Fit Engine #33752engineaddedengineFF Honda Fit engine adds Fast Forward part number alternatives for intake, exhaust, oil system, and scavenge pump components.
  • SRF3 Update SRF Brake Rule #33469enginefasterengineSRF removes 1985 Renault Alliance solid front rotor option; restrictor sizes decrease 1mm for newer Kawasaki and multi-brand engines; minimum weights increase to 1100 lbs.
  • SRF3 Update SRF Bodywork Fitment Rule #33765wordingwordingSRF3 alternate dash panel P/N 180100 or 180101 moved from optional to required bodywork section.
  • GTL Toyota 4Y Engine Classification Request #33562engineaddedengineGTL 3K, 4K, 5K Toyota engines may now use 4Y block only.
  • GTL Toyota 4A-F and 4A-FE 1.6L DOHC 16V Engine Request #33415cars addedaddedGT2 and GTL add Toyota 4A-F and 4A-FE 1.6L DOHC 16V engines as permitted options.
  • SM BOP for NB1 and NB2 #32309weightslowerweightSM Mazda MX-5 Miata 01-05 minimum weight rises to 2450 lbs, or 2465 with alternate bore.
  • GTL Fiat HP Limited Prep X1/9 Weight in GTL #33297weightslowerweightGTL Fiat X1/9 1500 Limited Prep minimum weight increases to 2000 lbs from 1835 lbs.
  • GTL GT2 (TA2)/GTA Part Number Update #33315wordingwordingGT2 TA2 and GTA throttle body part numbers updated to GM 12570790 or Edelbrock 33869/3870.
  • GTL Request to add Ford Festiva to GTL #33335cars addedaddedGTL adds Ford Festiva 1988-1993 FWD hatchback with Mazda B3 1324cc engine.
  • GTL Engine Request #33064cars addedaddedGTL adds Toyota G16E-GTS 1618cc DOHC 3-cyl engine, 1945 lbs, SIR, no turbo or direct injection.
Virginia International Raceway Runoffs 20222022-09-242:07.789Peter Shadowen · fastest of 14 · top 5 within 2.2s+0.792s (+0.62%)2:21.180Michael Lewis · fastest of 13 · top 5 within 2.1s+13.343s (+10.44%)136.0Peter Shadowen+4.9 mph (+3.7%)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%)-2.073squal +6.875s98.5%qual 105.4%2:03.716Franklin Futrelle · fastest of 44 · top 5 within 0.6s-0.908s (-0.73%)2:22.066Franklin Futrelle · fastest of 40 · top 5 within 1.2s+17.311s (+13.88%)134.5David Ogburn+2.1 mph (+1.6%)+0.886squal -4.073s100.6%qual 96.8%1:59.215Jonathan Kotyk · fastest of 13 · top 5 within 1.2s-0.348s (-0.29%)2:18.358Jonathan Kotyk · fastest of 12 · top 5 within 2.4s-2.116s (-1.51%)138.3Tim Kautz+2.2 mph (+1.6%)-2.822squal -8.574s98.0%qual 93.3%
7 rule changes (GTL: 3, SM: 1, SRF3: 3)2 cars added · 3 wording · 2 other · GT1, GT2, GT3, GTL, GTX tail lights may now be original style or custom panel graphic with functioning red LED brake lamps. · SRF tire rule wording clarified: tires must be run as delivered. · SRF brake rotor minimum thickness reduced from 13.25 mm to 12.20 mm; seals and air filter specs clarified. · SM Majors must run authorized Penske shock and mount; Regional competitors not required until further evaluation. · Ginetta G40 added to GTL with Ford Zetec 1796cc engine, 2050 lbs minimum weight, 22.5mm SIR. · SRF wet tyres front P185/65R13 W2 option added; air box clarified as-delivered; SRF3 restrictor plate G301048 mandatory Jan 1 2022; P2 motorcycle engines up to 1005cc with 35mm restrictor, 2009+ stock 1075 lbs, 2008 stock 1025 lbs, modifie… · GT3 Volkswagen Fun Cup Beetle EVO3 classified, sealed SOHC 1984cc engine, 2060 lbs minimum weight.showhide
  • GTL Tail lights on all GT category race cars. #32799wordingwordingGT1, GT2, GT3, GTL, GTX tail lights may now be original style or custom panel graphic with functioning red LED brake lamps.
  • SRF3 SRF Tire Rule Update #32614wordingwordingSRF tire rule wording clarified: tires must be run as delivered.
  • SRF3 Brake, seal, and air filter clarifications #32670otherfasterSRF brake rotor minimum thickness reduced from 13.25 mm to 12.20 mm; seals and air filter specs clarified.
  • SM Update GCR Section 9.1.7.3.A.1. #32217wordingwordingSM Majors must run authorized Penske shock and mount; Regional competitors not required until further evaluation.
  • GTL Request to Classify Ginetta G40 in GTL #31599cars addedaddedGinetta G40 added to GTL with Ford Zetec 1796cc engine, 2050 lbs minimum weight, 22.5mm SIR.
  • SRF3 Three Updates to SRF Rules #31523otherotherSRF wet tyres front P185/65R13 W2 option added; air box clarified as-delivered; SRF3 restrictor plate G301048 mandatory Jan 1 2022; P2 motorcycle engines up to 1005cc with 35mm restrictor, 2009+ stock 1075 lbs, 2008 stock 1025 lbs, modifie…
  • GTL Request car classification #31032cars addedaddedGT3 Volkswagen Fun Cup Beetle EVO3 classified, sealed SOHC 1984cc engine, 2060 lbs minimum weight.
Indianapolis Motor Speedway Runoffs 20212021-09-251:51.819Christopher Bovis · fastest of 22 · top 5 within 1.8s+1.488s (+1.35%)1:51.952Scott Twomey · fastest of 19 · top 5 within 1.7s-0.116s (-0.10%)129.5Brian Linn1:57.695Brian 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+6.885squal +5.876s106.1%qual 105.3%1:49.520Franklin Futrelle · fastest of 84 · top 5 within 0.5s-0.304s (-0.28%)1:50.095John Black · fastest of 82 · top 5 within 0.2s+0.313s (+0.29%)132.1Matthew Horst-1.857squal -2.299s98.3%qual 97.9%1:44.359Jonathan Kotyk · fastest of 24 · top 5 within 1.1s-0.242s (-0.23%)1:55.676Jonathan Kotyk · fastest of 23 · top 5 within 1.8s+11.152s (+10.67%)141.6Nicholas Sheppard+3.724squal -7.460s103.3%qual 93.3%
18 rule changes (GTL: 8, SM: 1, SRF3: 6, FF: 3)4 cars added · 2 induction · 1 aero · 1 engine · 1 tyres & wheels · 6 wording · 3 other · GTA part numbers updated: 0-80541-1 to 0-80541-2 in two locations and 6010 to 6014X in TA2 Appendix. · SRF wet tyres add Hoosier W2 option alongside existing H20 from October 4, 2021. · SRF adds SADEV-SRF3 6-speed sequential transmission option with ratios 3.0–0.92:1 and 3.20 final drive. · SRF seal requirements clarified: seals now must be on driveline components in designated locations; unsealed components removed and inspected by CSR or Enterprises rather than engine shipped for testing. · GTL Honda B18 split into B18A/B at 1797 cc 2050 lbs and B18C at 1834 cc 2065 lbs. · GTL Nissan B13 Sentra may have hood bulge maximum 1.5 inches high by 10.0 long by 6.0 wide. · unclear · SRF3 alternator pulley specified as P/N G902130 or G902130A, minimum 12oz. · FF block relief permitted only as needed to fit an allowed crankshaft. · SM adds procedure for CRB-approved obsolete parts and BOP testing in sanctioned events with point forfeiture. · GTL Mazda 12A SIR increases to 29mm, minimum weight rises to 2000 lbs, 28mm SIR option with 175 lb penalty removed. · SRF and SRF3 mandatory identification revised: removed Ford Performance and Blue Oval decals, added Hoosier logo placement. · GTL adds FIAT X-1/9 Bertone 1500 SOHC, 1498 cc, 2000 lbs, fuel injection or carburetors permitted. · GTL Nissan MRA8DE 1.8L engine added, 1797 cc, DOHC, 2050 lbs minimum weight. · GTL Mazda 13B SIR increases from 26 mm to 28 mm; 27 mm option with 175 lbs removed. · FF class cylinder head now permits optional coolant bleed line pipe thread fitting to swirl tower. · FF Honda LC1 ECU supplied by HPD is permitted effective 12/1/2020 with HPD lambda sensor. · SRF rear springs limited to P/N 280390 only, previous part numbers no longer allowed; ground clearance wording clarified.showhide
  • GTL Request to Update GTA Obsolete Part Numbers #30615wordingwordingGTA part numbers updated: 0-80541-1 to 0-80541-2 in two locations and 6010 to 6014X in TA2 Appendix.
  • SRF3 SRF Wet Tires #30849tyres & wheelsaddedtyres & wheelsSRF wet tyres add Hoosier W2 option alongside existing H20 from October 4, 2021.
  • SRF3 SADEV-SRF3 Transmission #30926cars addedaddedSRF adds SADEV-SRF3 6-speed sequential transmission option with ratios 3.0–0.92:1 and 3.20 final drive.
  • SRF3 SRF Update Maintenance, Repairs and Seals #30961wordingwordingSRF seal requirements clarified: seals now must be on driveline components in designated locations; unsealed components removed and inspected by CSR or Enterprises rather than engine shipped for testing.
  • GTL Request clarification for the Honda B18a,bVS B18c #30482cars addedaddedGTL Honda B18 split into B18A/B at 1797 cc 2050 lbs and B18C at 1834 cc 2065 lbs.
  • GTL Request to Allow Hood Bulge on Nissan B13 Sentra #30504aeroaddedaeroGTL Nissan B13 Sentra may have hood bulge maximum 1.5 inches high by 10.0 long by 6.0 wide.
  • GTL Request BMW E21 Classing #30582otherunclearunclear
  • SRF3 SRF3 Alternator Pulley #30684engineaddedengineSRF3 alternator pulley specified as P/N G902130 or G902130A, minimum 12oz.
  • FF Kent crankshaft clarification #30426wordingwordingFF block relief permitted only as needed to fit an allowed crankshaft.
  • SM Updates - Obsolete Parts & BOP Parts #30438wordingaddedSM adds procedure for CRB-approved obsolete parts and BOP testing in sanctioned events with point forfeiture.
  • GTL Request for Help for Mazda 12A #29754induction +50 lbsslowerinductionGTL Mazda 12A SIR increases to 29mm, minimum weight rises to 2000 lbs, 28mm SIR option with 175 lb penalty removed.
  • SRF3 Mandatory identification: #30223wordingwordingSRF and SRF3 mandatory identification revised: removed Ford Performance and Blue Oval decals, added Hoosier logo placement.
  • GTL Request LP HP Fiat X1/9 & Bertone 1500 to GTL #30058cars addedaddedGTL adds FIAT X-1/9 Bertone 1500 SOHC, 1498 cc, 2000 lbs, fuel injection or carburetors permitted.
  • GTL Please Add GTL Nissan 1.8L Engine MRA8DE #29805cars addedaddedGTL Nissan MRA8DE 1.8L engine added, 1797 cc, DOHC, 2050 lbs minimum weight.
  • GTL Increase 13b SIR size #29867inductionfasterinductionGTL Mazda 13B SIR increases from 26 mm to 28 mm; 27 mm option with 175 lbs removed.
  • FF Allow Optional Coolant Bleed Line to Correct a Known Problem #29673otheraddedFF class cylinder head now permits optional coolant bleed line pipe thread fitting to swirl tower.
  • FF Clarification regarding Honda LC1 ECU implementation date #29684wordingwordingFF Honda LC1 ECU supplied by HPD is permitted effective 12/1/2020 with HPD lambda sensor.
  • SRF3 SRF Shocks, Springs and Ride Height. #29688otherotherSRF rear springs limited to P/N 280390 only, previous part numbers no longer allowed; ground clearance wording clarified.
Road America Runoffs 20202020-10-022:31.943Chris Bovis · fastest of 14 · top 5 within 6.3s2:31.601Peter Shadowen · fastest of 14 · top 5 within 7.2s131.4Peter Shadowen2:42.209Kyle Greenhill · fastest of 77 · top 5 within 0.5s2:43.748Preston Pardus · fastest of 75 · top 5 within 1.0s121.3Kyle Greenhill+12.147squal +10.266s108.0%qual 106.8%2:29.786TJ Acker · fastest of 59 · top 5 within 0.5s2:31.038Justin Hille · fastest of 55 · top 5 within 0.2s131.9Charles Russell Turner-0.563squal -2.157s99.6%qual 98.6%2:22.916Simon Sikes · fastest of 14 · top 5 within 1.6s2:24.268Jeffrey Bartz · fastest of 14 · top 5 within 0.4s138.1Jeffrey Bartz-7.333squal -9.027s95.2%qual 94.1%
30 rule changes (GTL: 17, SM: 2, SRF3: 7, FF: 4)4 aero · 3 cars added · 3 suspension & brakes · 2 engine · 2 tyres & wheels · 2 weight · 1 induction · 12 wording · 1 other · SM allows aftermarket radiators in original location with stock OEM cooling fan, and permits 1990-1997 cars to install upper radiator seal NA75-50-OK7A. · GT1/GT2/GT3/GTL/GTX turbocharging and supercharging now permitted if listed on spec line. · FF Honda LC1 ECU implementation date clarified to pending, contingent on SCCA receiving sufficient support materials. · GTL Mazda 13B restrictor increases from 24mm to 26mm SIR, minimum weight rises to 2125 lbs, alternative 27mm SIR option adds 175 lbs. · SM rear brake caliper may use single bracket under upper retaining bolt head to prevent pin failure. · GTL: Toyota MR2 Spyder 1999–2007 newly classified for GTL competition. · TA2 Gurney flap wording clarified: replace 'wicker bill' and 'wicker' with 'Gurney flap' throughout wing specifications. · STO rear wing rules clarify that wicker is called Gurney flap in two places; no performance change. · GT Gurney flap wording clarified: wickerbill and tab terminology replaced with Gurney flap throughout sections 9.1.2.F.7.b. · GTL Mazda 13B restrictor size addressed in response to letter 28518; see that letter for details. · GTL SIR stall test procedure clarified: system tested as raced, competitor must prevent air bypass behind restrictor. · SRF3 shocks no longer require the same brand in all positions; only SCCA P/N 280407 bump stops allowed, one per shock, all must be sealed by Enterprises. · GTL wing mount openings excluded from square inch area limit. · SRF3 bump stop must be SCCA P/N 280407, no modifications, optional, maximum one per shock. · SRF Penske shock P/N 280396 bump stop P/N 280407 becomes mandatory, maximum one per shock, effective 05/01/2020. · FF Kent Engine alternator becomes optional instead of not required. · FF permits HPD LC1 ECU with lambda sensor; E1 ECU no longer supported but existing units may continue. · FF rain tyres now allow Hoosier W3 Radial 185/60R13 front and 205/60R13 rear. · GTL wing mounting posts limited to 85 square inches exposed area each, measured flat from side view. · GTL wing mounting posts limited to 85 square inches each, measured flat from side view. · GTL wing endplates maximum area increased to 64 square inches from 8.5 by 3.0 inches rectangle. · GTL Mazda 12A street port minimum weight drops to 1950 lbs. · GT1, GT2, GT3, GTL, GTX may use bonded-glass factory windshields without clips or straps if attached per original specifications. · GTX Misc. adds Factory Five Type 65 Coupe R Ford 302/351 and 5.0/5.2L NA at 2600 lbs, plus Ferrari 458/488 Challenge, Ford FP350S, Chevrolet C6, Lamborghini Super Trofeo. · GTL adds Jetta Mk1 two-door classification effective 2020-01-01. · SRF rain and brake rule supersedes GCR 9.3.32.B.2 effective 1/1/2024 through 12/31/2024. · GTL Honda CRX 84-87 and 88-91 lose permission to use IRS with 2.5% weight penalty. · SRF adds tire warmer prohibition and specifies Hoosier dry and wet tire part numbers. · SRF front nose weight minimum reduced from 35 to 32 lbs. · SRF2 becomes Regional Only; SRF3 nomenclature changed from GEN3 to Ford 1.6L conversion; SRF and SRF3 no longer compete together for points.showhide
  • SM Radiator E&O Clarifications #29294wordingwordingSM allows aftermarket radiators in original location with stock OEM cooling fan, and permits 1990-1997 cars to install upper radiator seal NA75-50-OK7A.
  • GTL GT Category Wording #29193wordingaddedGT1/GT2/GT3/GTL/GTX turbocharging and supercharging now permitted if listed on spec line.
  • FF Clarification regarding Honda LC1 ECU implementation #29135wordingwordingFF Honda LC1 ECU implementation date clarified to pending, contingent on SCCA receiving sufficient support materials.
  • GTL Request to change the Mazda 13b restrictor size #28518induction +175 lbsfasterinductionGTL Mazda 13B restrictor increases from 24mm to 26mm SIR, minimum weight rises to 2125 lbs, alternative 27mm SIR option adds 175 lbs.
  • SM Modifications to prevent failures of Rear Brake Caliper Pin #28953suspension & brakessuspension & brakesSM rear brake caliper may use single bracket under upper retaining bolt head to prevent pin failure.
  • GTL Request to classify 1999-2007 Toyota MR2 Spyder body #28870cars addedaddedGTL: Toyota MR2 Spyder 1999–2007 newly classified for GTL competition.
  • GTL TA2 Gurney flap wicker clarification #28874wordingwordingTA2 Gurney flap wording clarified: replace 'wicker bill' and 'wicker' with 'Gurney flap' throughout wing specifications.
  • GTL STO Gurney flap wicker clarification #28883wordingwordingSTO rear wing rules clarify that wicker is called Gurney flap in two places; no performance change.
  • GTL GT Gurney flap wicker clarification #28909wordingwordingGT Gurney flap wording clarified: wickerbill and tab terminology replaced with Gurney flap throughout sections 9.1.2.F.7.b.
  • GTL Mazda 13b Restrictor Size Follow up to Letter 28518 #29015wordingunclearGTL Mazda 13B restrictor size addressed in response to letter 28518; see that letter for details.
  • GTL Stall Test #28709wordingwordingGTL SIR stall test procedure clarified: system tested as raced, competitor must prevent air bypass behind restrictor.
  • SRF3 SRF Shocks #28791wordingwordingSRF3 shocks no longer require the same brand in all positions; only SCCA P/N 280407 bump stops allowed, one per shock, all must be sealed by Enterprises.
  • GTL GTL Wing Rule #28754aeroaddedaeroGTL wing mount openings excluded from square inch area limit.
  • SRF3 Update Bump Stop Rule #28712suspension & brakessuspension & brakesSRF3 bump stop must be SCCA P/N 280407, no modifications, optional, maximum one per shock.
  • SRF3 SRF Bump Stop Correction #27019wordingwordingSRF Penske shock P/N 280396 bump stop P/N 280407 becomes mandatory, maximum one per shock, effective 05/01/2020.
  • FF E&O FF Kent Engine alternator language #28204engineaddedengineFF Kent Engine alternator becomes optional instead of not required.
  • FF Honda Racing HPD low cost ECU proposal #27563engineaddedengineFF permits HPD LC1 ECU with lambda sensor; E1 ECU no longer supported but existing units may continue.
  • FF Update rain tire designation #28443tyres & wheelsaddedtyres & wheelsFF rain tyres now allow Hoosier W3 Radial 185/60R13 front and 205/60R13 rear.
  • GTL Wing Mounting Upright Size #27641aeroaeroGTL wing mounting posts limited to 85 square inches exposed area each, measured flat from side view.
  • GTL Wing Mounting Upright Size #27641aeroaeroGTL wing mounting posts limited to 85 square inches each, measured flat from side view.
  • GTL GTL wing end plates addition #28243aerofasteraeroGTL wing endplates maximum area increased to 64 square inches from 8.5 by 3.0 inches rectangle.
  • GTL Clarification to letter #27406 #28309weight -50 lbsfasterweightGTL Mazda 12A street port minimum weight drops to 1950 lbs.
  • GTL Windshield Clips #27323otheraddedGT1, GT2, GT3, GTL, GTX may use bonded-glass factory windshields without clips or straps if attached per original specifications.
  • GTL Request Factory Five Daytona coupe classification #26308cars addedaddedGTX Misc. adds Factory Five Type 65 Coupe R Ford 302/351 and 5.0/5.2L NA at 2600 lbs, plus Ferrari 458/488 Challenge, Ford FP350S, Chevrolet C6, Lamborghini Super Trofeo.
  • GTL Request to Classify the MK1 two door Jetta #27648cars addedaddedGTL adds Jetta Mk1 two-door classification effective 2020-01-01.
  • SRF3 SRF Rain / Brake Rule - BoD approved as follows #34958wordingwordingSRF rain and brake rule supersedes GCR 9.3.32.B.2 effective 1/1/2024 through 12/31/2024.
  • GTL 88-91 Honda CRX Spec Line Correction #27233suspension & brakesremovedsuspension & brakesGTL Honda CRX 84-87 and 88-91 lose permission to use IRS with 2.5% weight penalty.
  • SRF3 SRF Tire Warmer Rule #27622tyres & wheelstyres & wheelsSRF adds tire warmer prohibition and specifies Hoosier dry and wet tire part numbers.
  • SRF3 SRF / SRF3 Nose Weight Reduction #27706weightfasterweightSRF front nose weight minimum reduced from 35 to 32 lbs.
  • SRF3 SRF / SRF3 Majors & Regional Class Updates #27723wordingwordingSRF2 becomes Regional Only; SRF3 nomenclature changed from GEN3 to Ford 1.6L conversion; SRF and SRF3 no longer compete together for points.
Virginia International Raceway Runoffs 20192019-10-052:06.997Peter Shadowen · fastest of 19 · top 5 within 4.0s2:07.837Bill Ball · fastest of 18 · top 5 within 4.2s131.1Peter Shadowen2:14.552Todd Buras · fastest of 60 · top 5 within 0.2s2:16.459Elivan Goulart · fastest of 56 · top 5 within 0.4s119.8Jim Drago+8.622squal +7.555s106.7%qual 105.9%2:04.624Brian Schofield · fastest of 54 · top 5 within 0.6s2:04.755Bobby Sak · fastest of 53 · top 5 within 0.3s132.4Bobby Sak-3.082squal -2.373s97.6%qual 98.1%1:59.563Tyler O'Connor · fastest of 14 · top 5 within 1.4s2:20.474Jonathan Kotyk · fastest of 14 · top 5 within 6.3s136.2Derek Ketchie+12.637squal -7.434s109.9%qual 94.1%
23 rule changes (GTL: 13, SM: 4, SRF3: 3, FF: 3)4 cars added · 3 aero · 3 engine · 1 induction · 1 removed · 1 weight · 6 wording · 4 other · GTL Fun Cup Beetle engine weight set to 1850 lbs with Weber DMTL 32/34 induction. · GTL Fun Cup Beetle removes reference to VW engine table; Fun Cup engines only permitted. · GTL Honda CRZ 10-14, CRZ 15-16, and Insight 00-06 gain alternate wheelbase option of 90.6 inches. · SRF drivers may now use Dash Windscreen Kit P/N 1180103 or P/N 180102. · SRF3 multi-piece nose assembly approved for use; no other nose modifications allowed. · GTL Fun Cup Beetle added, all model years, 2-door RWD, 94.5 in wheelbase, VW Fun Cup spec chassis. · GTX tube frame cars now allowed fuel injection with maximum 90mm throttle body. · GTX adds Ligier JS2 R classification with restrictor and minimum weight. · GTL Mazda 13B may use 25mm SIR with 175 lbs weight penalty added. · SRF3 brakes now accept Hawk Blue 9012 pads P/N 801993 only; Wilwood vented rotor P/N 800065 minimum 13.25mm as delivered; caliper bushings P/N 1196185 A or B permitted. Shock absorbers: Penske P/N 280396 only, sealed, with SCCA bump rubber… · GT1 and GT2/3/Lite remove ride height ground clearance rules; cars may now touch ground when tires deflate. · GTL Mazda 12A may use 28mm SIR plus 175 lbs. · GTL: Ford Mustang 94-04 body newly classified for GTL racing. · SM fuel pump and filter now permitted as Mazda or OEM equivalent part. · FF Honda Fit cylinder honing increased to 73.315mm and oversize pistons PN 13020-RB7-Z00 now permitted with matching ring packs. · FF intake manifold thermal wrap now permitted if easily removable for inspection; no coating allowed. · FF clarifies coolant and oil catch tank capacity requirements: coolant minimum one U.S. pint, oil minimum one U.S. quart per system. · SM allows factory Mazda ECU and injector harnesses (P/N 0000-10-020E-99, 0000-10-080D-99) on 1999–2000 model year cars, unmodified. · SM electrical rules reorganized and clarified; alternator now externally regulated only by OEM ECU or master kill switch; harness repair by splicing permitted. · SM tire tread protrusion language removed from GCR 9.1.7.C.5. · GTL Mini 1275–1399 Iron and Aluminum Crossflow with OE common sump gearbox reduce weight by 125 lbs, up from 50 lbs. · GTL BMC thru Rover Group removes four long inactive Mini engines: 948, 970, 1071, 1098. · GTX FIA GT3: Audi R8 now 40 mm restrictor and 2900 lbs; BMW Z4 now 70 mm restrictor and 2800 lbs; Ferrari 488 now 35 mm restrictor, TIR, and 3025 lbs.showhide
  • GTL Fun Cup Beetle #27334wordingwordingGTL Fun Cup Beetle engine weight set to 1850 lbs with Weber DMTL 32/34 induction.
  • GTL GTL #26960wordingwordingGTL Fun Cup Beetle removes reference to VW engine table; Fun Cup engines only permitted.
  • GTL Request CRZ wheelbase change #26896cars addedaddedGTL Honda CRZ 10-14, CRZ 15-16, and Insight 00-06 gain alternate wheelbase option of 90.6 inches.
  • SRF3 SRF Dash Windscreen Kit #27028aeroaddedaeroSRF drivers may now use Dash Windscreen Kit P/N 1180103 or P/N 180102.
  • SRF3 New SRF Sectional Nose Rule Addition #26914aeroaddedaeroSRF3 multi-piece nose assembly approved for use; no other nose modifications allowed.
  • GTL Request to Classify VW Fun Cup Beetle #25986cars addedaddedGTL Fun Cup Beetle added, all model years, 2-door RWD, 94.5 in wheelbase, VW Fun Cup spec chassis.
  • GTL Request GTX Fuel injection for previous GT-1 tube frame cars #26141engineaddedengineGTX tube frame cars now allowed fuel injection with maximum 90mm throttle body.
  • GTL Request to Classify Ligier JS2 R #26535cars addedaddedGTX adds Ligier JS2 R classification with restrictor and minimum weight.
  • GTL Request for GTL Mazda 13B SIR Increase with Penalty #26572engineaddedengineGTL Mazda 13B may use 25mm SIR with 175 lbs weight penalty added.
  • SRF3 SRF Brakes and Shock Rule Changes #26629otherotherSRF3 brakes now accept Hawk Blue 9012 pads P/N 801993 only; Wilwood vented rotor P/N 800065 minimum 13.25mm as delivered; caliper bushings P/N 1196185 A or B permitted. Shock absorbers: Penske P/N 280396 only, sealed, with SCCA bump rubber…
  • GTL Request Ride Height Clarification #26600wordingfasterGT1 and GT2/3/Lite remove ride height ground clearance rules; cars may now touch ground when tires deflate.
  • GTL Request Mazda 12a Rotary SIR Increase #26081inductionaddedinductionGTL Mazda 12A may use 28mm SIR plus 175 lbs.
  • GTL Request to Classify Mustang 2 Body in GTL #26222cars addedaddedGTL: Ford Mustang 94-04 body newly classified for GTL racing.
  • SM Request to allow aftermarket fuel filters. #26370otheraddedSM fuel pump and filter now permitted as Mazda or OEM equivalent part.
  • FF Request for Oversize Honda Fit Pistons #25810enginefasterengineFF Honda Fit cylinder honing increased to 73.315mm and oversize pistons PN 13020-RB7-Z00 now permitted with matching ring packs.
  • FF Heat Shield - Fit Intake #26102aeroaddedaeroFF intake manifold thermal wrap now permitted if easily removable for inspection; no coating allowed.
  • FF Request catch cans/tanks clarification #26158wordingwordingFF clarifies coolant and oil catch tank capacity requirements: coolant minimum one U.S. pint, oil minimum one U.S. quart per system.
  • SM Request 99-00 replacement Wire harnesses #25602otheraddedSM allows factory Mazda ECU and injector harnesses (P/N 0000-10-020E-99, 0000-10-080D-99) on 1999–2000 model year cars, unmodified.
  • SM Organize and Clarify 9.1.7.C.1.o. #25913wordingwordingSM electrical rules reorganized and clarified; alternator now externally regulated only by OEM ECU or master kill switch; harness repair by splicing permitted.
  • SM Strike Tire Tread Language #26123wordingremovedSM tire tread protrusion language removed from GCR 9.1.7.C.5.
  • GTL Request for GTL Mini Adjustments #25754weightfasterweightGTL Mini 1275–1399 Iron and Aluminum Crossflow with OE common sump gearbox reduce weight by 125 lbs, up from 50 lbs.
  • GTL BMC thru Rover Group remove long inactive mini #25771removedremovedGTL BMC thru Rover Group removes four long inactive Mini engines: 948, 970, 1071, 1098.
  • GTL GTX Homologation table update #26034otherunclearGTX FIA GT3: Audi R8 now 40 mm restrictor and 2900 lbs; BMW Z4 now 70 mm restrictor and 2800 lbs; Ferrari 488 now 35 mm restrictor, TIR, and 3025 lbs.
Sonoma Raceway Runoffs 20182018-10-101:47.885Troy Ermish · fastest of 20 · top 5 within 4.5s1:49.458Troy Ermish · fastest of 19 · top 5 within 3.6s109.3Charles Leonard1:54.355Ken Sutherland · fastest of 48 · top 5 within 0.7s1:55.278Michael Carter · fastest of 48 · top 5 within 0.3s102.2Danny Steyn+5.820squal +6.470s105.3%qual 106.0%1:46.117Robeson Clay Russell · fastest of 36 · top 5 within 0.5s1:47.053TJ Acker · fastest of 35 · top 5 within 0.2s110.2Steve Fogg-2.405squal -1.768s97.8%qual 98.4%1:41.612Jonathon Kotyk · fastest of 22 · top 5 within 1.7s1:42.049Jonathon Kotyk · fastest of 22 · top 5 within 1.3s115.7Denny Renfrow-7.409squal -6.273s93.2%qual 94.2%
No rule changes on record between these events
Indianapolis Motor Speedway Runoffs 20172017-09-251:50.331Christopher Bovis · fastest of 26 · top 5 within 1.5s1:52.068Christopher Bovis · fastest of 20 · top 5 within 1.0s1:58.306Chris Haldeman · fastest of 86 · top 5 within 0.5s1:59.100Michael Gagliardo · fastest of 83 · top 5 within 0.6s+7.032squal +7.975s106.3%qual 107.2%1:49.824John Black · fastest of 101 · top 5 within 0.5s1:49.782Tray Ayres · fastest of 94 · top 5 within 0.4s-2.286squal -0.507s98.0%qual 99.5%1:44.601Zach Holden · fastest of 36 · top 5 within 1.2s1:44.524Jonathon Kotyk · fastest of 36 · top 5 within 0.5s-7.544squal -5.730s93.3%qual 94.8%
No rule changes on record between these events
Mid-Ohio Sports Car Course Runoffs 20162016-09-191:35.377Wilson Wright · fastest of 28 · top 5 within 1.2s1:35.912Kyle Disque · fastest of 28 · top 5 within 1.1s1:40.514Justin Hille · fastest of 45 · top 5 within 0.3s1:40.764Michael Carter · fastest of 44 · top 5 within 0.3s+4.852squal +5.137s105.1%qual 105.4%1:34.363John Black · fastest of 41 · top 5 within 0.5s1:34.947Cliff White · fastest of 39 · top 5 within 0.3s-0.965squal -1.014s99.0%qual 98.9%1:29.213Neil Verhagen · fastest of 14 · top 5 within 2.1s1:30.133Neil Verhagen · fastest of 14 · top 5 within 1.4s-5.779squal -6.164s94.0%qual 93.5%
No rule changes on record between these events
Daytona International Speedway Runoffs 20152015-09-212:11.387Jim Dentici · fastest of 10 · top 5 within 2.2s2:13.564Jim Dentici · fastest of 9 · top 5 within 2.0s2:18.661Andrew Carbonell · fastest of 62 · top 5 within 0.6s2:24.067Todd Lamb · fastest of 59 · top 5 within 0.8s+10.503squal +7.274s107.9%qual 105.5%2:08.557Kerry Jacobsen · fastest of 29 · top 5 within 1.1s2:10.215Chad Galloway · fastest of 29 · top 5 within 0.3s-3.349squal -2.830s97.5%qual 97.8%2:02.489Tim Kautz · fastest of 25 · top 5 within 1.1s2:03.383Rick Payne · fastest of 22 · top 5 within 0.8s-10.181squal -8.898s92.4%qual 93.2%

By track

TrackEvents Typical % of GTL Best Latest 
Road America4100.0%2 of 4 with GTL100.0%Runoffs 2020100.0%Runoffs 2024
Virginia International Raceway3100.0%100.0%Runoffs 2019100.0%Runoffs 2023
Indianapolis Motor Speedway2100.0%100.0%Runoffs 2017100.0%Runoffs 2021
Daytona International Speedway1100.0%100.0%Runoffs 2015100.0%Runoffs 2015
Mid-Ohio Sports Car Course1100.0%100.0%Runoffs 2016100.0%Runoffs 2016
Sonoma Raceway1100.0%100.0%Runoffs 2018100.0%Runoffs 2018
About this data
Every event the class ran, at any track, oldest to newest on the chart and newest first in the table. Each point is the class's best lap as a share of GTL'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.