BoP Lab / Classes / FM

FM vs AS vs GTL pace at every track

Lap times across years say as much about the weather as the class. % of FM is each class's best lap as a share of FM'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)

vsAS ×B-Spec +EP +FA +FC +FE2 +FF +FM×FP +FV +FX +GT1 +GT2 +vsGTL ×GTX +HP +P +P2 +SM +SMX +SRF3 +STL +STU +T1 +T2 +T3 +T4 +Show 49 inactive classes

Series Runoffs Super Tour Both

Reference · what % is measured against

Tracks · untick to narrow Auto Club Speedway Barber Motorsports Park Blackhawk Farms Raceway Buttonwillow Raceway Park Circuit of St. Louis (formerly Gateway Motorsports Circuit of the Americas Daytona International Speedway Grattan Raceway Hallett Motor Racing Circuit Homestead-Miami Speedway Indianapolis Motor Speedway Laguna Seca Michelin Raceway Road Atlanta Mid-Ohio Sports Car Course New Jersey Motorsports Park NOLA Motorsports Park Pacific Raceways Pittsburgh International Race Complex Portland International Raceway Pueblo Motorsports Park Road America Sebring International Raceway Sonoma Raceway Summit Point Raceway Thunderhill Raceway Park Virginia International Raceway Watkins Glen International Willow Springs Raceway World Wide Technology Raceway

Closest to the field: FM 100.0% of FM Joseph Burton-Harris, Daytona International Speedway Runoffs 2015 race · AS 91.2% of FM James Jost, Virginia International Raceway Runoffs 2019 race · GTL 94.1% of FM Bill Ball, Virginia International Raceway Runoffs 2019 race

% of FMLap times

FMASGTLsolid race · dashed qualifying · slower is lower

FMASGTLsolid race · dashed qualifying · each class's best lap as a share of FM's at the same event (the reference class, changeable above); 100% is level, less is quicker, so up the chart is quicker

	Event	FM			AS					GTL
	Event	Qual best	Race best	Trap	Qual best	Race best	Trap	vs FM	% of FM	Qual best	Race best	Trap	vs FM	% of FM
	Road America Runoffs 20262026-09-28				2:26.911Andrew McDermid · fastest of 8 · top 5 within 3.4s+0.119s (+0.08%)	2:28.471Andrew McDermid · fastest of 8 · top 5 within 2.4s-0.761s (-0.51%)	151.0Andrew McDermid-0.6 mph (-0.4%)
14 rule changes (AS: 13, GTL: 1)5 weight · 3 engine · 2 removed · 2 tyres & wheels · 1 induction · 1 othershowhide 2026-09-01 AS 2016+ Camaro Spec Line Full Prep #39646tyres & wheels 2026-09-01 AS Consideration of Pirelli P Zero Trofeo Track for AS Competition #40495tyres & wheels 2026-08-01 AS Change in 9.1.6.D.4.d.5 in Suspension Mounting Points #40094other 2026-08-01 AS Re-Add 4.6L 4v 96-04 Mustang Cobra #40239weight 2026-08-01 AS Errors and Omissions #40532weight 2026-06-01 AS Clarification for LM7 Holley Carburetor #40167engine 2026-04-01 AS Header Information Update for EFI Engine Build Sheets #39886engine 2026-04-01 AS Errors and Omissions #39933weight 2026-03-01 AS Re-Organization of AS Spec lines for 2026 #39887removed 2026-03-01 GTL Remove GT3U from GCR as it is now in STU #39862removed 2026-02-01 AS Edelbrock manifold (& timing kit) to Chevy LS Spec Lines Request #39055weight 2026-01-01 AS Restrictor Plate Change for Gen 2 Ford Coyote Engine #39501induction 2025-12-01 AS 1994 Mustang Spec Line Request #39104engine 2025-11-01 AS Cadillac CTS-V BOP Weight Change #38640weight -50 lbs
	Road America Runoffs 20252025-09-29				2:26.792Andrew McDermid · fastest of 11 · top 5 within 3.9s+0.214s (+0.15%)	2:29.232Gregory Eaton · fastest of 10 · top 5 within 4.0s+2.803s (+1.91%)	151.5Andrew McDermid+1.9 mph (+1.3%)
14 rule changes (AS: 11, GTL: 3)6 engine · 4 weight · 2 induction · 1 aero · 1 othershowhide 2025-07-01 AS RE: Previous Letter 37695 Update #38245weight -75 lbs 2025-06-01 AS Errors and Omissions #38234engine 2025-05-01 AS Errors and Omission #38055induction 2025-05-01 AS Request to Add LS1/LS6 Intakes for 5.3L Truck Engine EnO #38197engine 2025-04-01 AS Flotek Head Plunge Cut Inconsistencies #37502other 2025-04-01 AS Notes clean up #37693weight 2025-03-01 AS Race memo #37902engine 2025-01-01 AS Increase Coyote Engine Restrictor to 80mm #36177induction 2025-01-01 AS Performance Pack for 2015+ Mustang #36867weight 2025-01-01 AS Gear Ratios #37131engine 2025-01-01 AS ECU specs for LS engine #37208engine 2025-01-01 GTL Correct language regarding OEM Areo Devices #37137aero 2024-11-01 GTL G16E-GTS Fuel Injection Spec Line Change #36588engine 2024-11-01 GTL GTL Alternate Weight and Choke Option for L16 engine #36653weight
	Road America Runoffs 20242024-10-01				2:26.578Gregory Eaton · fastest of 18 · top 5 within 2.6s-0.467s (-0.32%)	2:26.429Gregory Eaton · fastest of 18 · top 5 within 2.5s-1.239s (-0.84%)	149.6Gregory Eaton+0.4 mph (+0.3%)			2:30.858Peter 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%)
27 rule changes (AS: 11, GTL: 16)11 cars added · 6 engine · 3 weight · 2 induction · 1 aero · 1 tyres & wheels · 3 othershowhide 2024-09-01 AS Mustang transmission ratios #36662engine 2024-09-01 GTL Request to Include Toyota GR86 in GTL #36324cars added 2024-09-01 GTL Inclusion of Modified Spec Miata for GTL competition #36325cars added 2024-09-01 GTL Include Mazda MX5 RF 2017- in GTL #36428cars added 2024-07-01 GTL Add GTL to GT3 choke option line. #36236induction 2024-06-01 AS Request for Classification of 2018-2023 mustang In #35764cars added 2024-05-01 AS 6th gen Camaro limited prep #35733cars added 2024-05-01 AS Chevrolet/Pontiac Camaro & Firebird (82-92) 5.7L V8 LS1 Alum BLK #35825cars added 2024-05-01 AS Full Prep Head #35891other 2024-05-01 GTL Request for Spec Line 1010 Reconsideration #35009weight +300 lbs 2024-05-01 GTL Allow 34 mm chokes for the Datsun 510 #35661induction +50 lbs 2024-04-01 AS Restricted Prep Aftermarket Parts Request #35682other 2024-04-01 AS Allowance of 11 #35824tyres & wheels 2024-03-01 AS Request to Classify 1970-1981 Camaro and Firebird in AS #33659cars added 2024-03-01 AS Fuel Cell 12 #34194other 2024-03-01 AS Please Classify the 6th Gen Into AS. #35448cars added 2024-03-01 AS spec lines #35713cars added 2024-02-01 GTL Rear Blade Spoiler Clarification #35261aero 2024-02-01 GTL GT Direct Injection allowance and rules #35437engine 2024-02-01 GTL GT2/3 remove Direction Injection not allowed in Spec line notes #35439engine 2024-01-01 GTL Rotary Engine 12A Rotor Housings #35131engine 2024-01-01 GTL Request to Include Toyota GR86 in GTL #35198cars added 2024-01-01 GTL Errors and Omissions, GTL engines & Cars #35226engine 2023-12-01 GTL Small Engines in GT Lite #34842engine 2023-12-01 GTL Request to Classify Honda Fit body in GTL #35020cars added 2023-12-01 GTL Errors in GTCS Headings and Use of the Terms Category and ClassChange existing GTL and GTA Rules #34453weight 2023-11-01 GTL Weight for Nissan Sentra/200SX A 1400's #34918weight -50 lbs
	Virginia International Raceway Runoffs 20232023-09-23				2:03.082Daniel Richardson · fastest of 11 · top 5 within 2.2s+0.920s (+0.75%)	2:04.120Gregory Eaton · fastest of 9 · top 5 within 3.0s-0.458s (-0.37%)	154.6James Jost+3.7 mph (+2.5%)			2:09.564Peter 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%)
11 rule changes (AS: 4, GTL: 7)5 engine · 2 weight · 1 cars added · 1 induction · 1 suspension & brakes · 1 tyres & wheelsshowhide 2023-08-01 AS Crate Motor Part Numbers #32944engine 2023-08-01 AS Request wheel size change #33007tyres & wheels 2023-08-01 AS Alternative Upper Front Control Arms for Dodge Challenger #33352engine 2023-08-01 AS Front Brake Caliper Adapters for Dodge Challenger #33353suspension & brakes 2023-05-01 GTL Please classify Fields Cardinal V8 #33784cars added 2023-02-01 GTL Toyota 4Y Engine Classification Request #33562engine 2023-01-01 GTL Toyota 4A-F and 4A-FE 1.6L DOHC 16V Engine Request #33415engine 2022-12-01 GTL Fiat HP Limited Prep X1/9 Weight in GTL #33297weight 2022-12-01 GTL GT2 (TA2)/GTA Part Number Update #33315induction 2022-12-01 GTL Request to add Ford Festiva to GTL #33335weight 2022-11-01 GTL Engine Request #33064engine
	Virginia International Raceway Runoffs 20222022-09-24				2:02.162Kurt Rezzetano · fastest of 13 · top 5 within 2.3s-0.776s (-0.63%)	2:04.578Gregory Eaton · fastest of 11 · top 5 within 2.9s+0.678s (+0.55%)	150.9James Jost-3.0 mph (-2.0%)			2:07.789Peter 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%)
12 rule changes (AS: 9, GTL: 3)2 cars added · 2 suspension & brakes · 2 weight · 1 engine · 2 wording · 3 othershowhide 2022-09-01 AS Request to add Hoosier W2 #33031other 2022-09-01 AS correction of Dodge Challenger specification line #33151wording 2022-09-01 GTL Tail lights on all GT category race cars. #32799suspension & brakes 2022-07-01 AS Request CTS-V Spec Line Error Correction #30242weight 2022-03-01 GTL Request to Classify Ginetta G40 in GTL #31599cars added 2022-01-01 AS Proposed Revisions to SCCA GCR 2021 Appendix M, Part 3 #30295other 2022-01-01 AS specification line consolidation and correction #31846wording 2022-01-01 AS correction of SMG specification line #31847suspension & brakes 2022-01-01 AS Alternate cylinder heads for full prep engine builds - Evaluation #31851engine 2021-10-01 AS Request for adjustable Front Upper Control Arms on 4th Gen F-Body #30457other 2021-10-01 AS Request Pontiac GTO tire size change #30881weight 2021-10-01 GTL Request car classification #31032cars added
	Indianapolis Motor Speedway Runoffs 20212021-09-25				1:50.427Drew Cattell · fastest of 31 · top 5 within 1.9s+5.207s (+4.95%)	1:50.606Gregory Eaton · fastest of 28 · top 5 within 1.7s-0.901s (-0.81%)	153.8James Jost			1:51.819Christopher 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 Linn
22 rule changes (AS: 14, GTL: 8)8 weight · 4 cars added · 4 engine · 1 induction · 1 tyres & wheels · 3 wording · 1 othershowhide 2021-08-01 GTL Request to Update GTA Obsolete Part Numbers #30615wording 2021-07-01 GTL Request clarification for the Honda B18a,bVS B18c #30482weight 2021-07-01 GTL Request to Allow Hood Bulge on Nissan B13 Sentra #30504other 2021-07-01 GTL Request BMW E21 Classing #30582tyres & wheels 2021-06-01 AS Request CTS-V Spec Line Error Correction #30242weight 2021-06-01 AS Request to consolidate SN95 Mustang '94-'04 Mustang spec lines #30428cars added 2021-06-01 AS American Sedan Transmission Rule Change Request #30595weight 2021-06-01 AS Correction to specifications inadvertently deleted #30691wording 2021-06-01 AS weight adjustments #30700weight +50 lbs 2021-03-01 AS AS Mustang LP 4.6 3V Classification Transmission Request #29886weight 2021-03-01 AS Request CF driveshaft on CTS-V for durability improvement #30117engine 2021-03-01 AS Adjustment to model years of 5th generation RP Camaro #30348engine 2021-03-01 GTL Request for Help for Mazda 12A #29754weight +50 lbs 2021-02-01 GTL Request LP HP Fiat X1/9 & Bertone 1500 to GTL #30058cars added 2021-01-01 AS Request for 2015 -2017 Ford Mustang Spec Line #29514cars added 2021-01-01 AS Request Trunk lid / Rear Hatch clarification #29591wording 2021-01-01 AS Common Weight for CTS-V Tire #29759weight 2021-01-01 AS Correction to specifications inadvertently deleted #30041cars added 2021-01-01 GTL Please Add GTL Nissan 1.8L Engine MRA8DE #29805engine 2021-01-01 GTL Increase 13b SIR size #29867induction 2020-12-01 AS Request Additional Engine Options for Dodge Challenger Spec Line #29543engine 2020-12-01 AS Rule simplification spec line communization #29824weight
	Road America Runoffs 20202020-10-02				2:27.045Gregory Eaton · fastest of 18 · top 5 within 0.6s	2:27.668Gregory Eaton · fastest of 15 · top 5 within 1.5s	149.2Gregory Eaton			2:31.943Chris Bovis · fastest of 14 · top 5 within 6.3s	2:31.601Peter Shadowen · fastest of 14 · top 5 within 7.2s	131.4Peter Shadowen
33 rule changes (AS: 16, GTL: 17)8 aero · 6 induction · 5 cars added · 4 weight · 3 engine · 2 suspension & brakes · 2 tyres & wheels · 3 othershowhide 2020-09-01 GTL GT Category Wording #29193induction 2020-08-01 AS Dodge Challenger AS Spec Line Clarification #28698induction 2020-08-01 AS Dodge Challenger AS Spec Line Clarification #2 #28699aero 2020-08-01 GTL Request to change the Mazda 13b restrictor size #28518induction +175 lbs 2020-07-01 AS Support for R-Type Specification Tires #27450tyres & wheels 2020-07-01 AS Spec Tire Request #27519tyres & wheels 2020-07-01 AS Restrictor Plate Change for RP 2011+ Mustang with Coyote Engine #27675induction 2020-07-01 AS 2005-2009 Restricted Prep 4.6 3V #27908engine 2020-07-01 AS Request for 2005-2009 Restricted Prep 4.6 3V Parts #27909engine 2020-07-01 AS Request for Full Preparation Classification for 2010-2014 Camaro #28030other 2020-07-01 AS Cylinder Heads #28696engine 2020-07-01 AS Request for Max Rotor Diameter Change #28748suspension & brakes 2020-07-01 AS Request increase rotor diameter #28797other 2020-07-01 GTL Request to classify 1999-2007 Toyota MR2 Spyder body #28870cars added 2020-07-01 GTL TA2 Gurney flap wicker clarification #28874aero 2020-07-01 GTL STO Gurney flap wicker clarification #28883aero 2020-07-01 GTL GT Gurney flap wicker clarification #28909aero 2020-07-01 GTL Mazda 13b Restrictor Size Follow up to Letter 28518 #29015induction 2020-06-01 GTL Stall Test #28709induction 2020-05-01 AS weight adjustments for 2020 season #28785weight -50 lbs 2020-05-01 GTL GTL Wing Rule #28754aero 2020-03-01 GTL Wing Mounting Upright Size #27641aero 2020-03-01 GTL Wing Mounting Upright Size #27641aero 2020-03-01 GTL GTL wing end plates addition #28243aero 2020-03-01 GTL Clarification to letter #27406 #28309weight -50 lbs 2020-02-01 AS Rear Trailing Arms #28007suspension & brakes 2020-02-01 AS Weight reduction for cars running iron heads #28010weight 2020-02-01 AS 05-10 Mustang with HR cam classification #28226cars added 2020-02-01 AS 10-15 Camaro Full Prep classification #28227cars added 2020-02-01 GTL Windshield Clips #27323other 2020-01-01 GTL Request Factory Five Daytona coupe classification #26308cars added 2020-01-01 GTL Request to Classify the MK1 two door Jetta #27648cars added 2019-12-01 GTL 88-91 Honda CRX Spec Line Correction #27233weight
	Virginia International Raceway Runoffs 20192019-10-05	1:55.124Bryce Cornet · fastest of 8 · top 5 within 2.3s	2:15.816Bryce Cornet · fastest of 8 · top 5 within 4.9s	135.7Bryce Cornet	2:02.938Gregory Eaton · fastest of 17 · top 5 within 0.8s	2:03.900James Jost · fastest of 16 · top 5 within 2.1s	153.9James Jost	-11.916squal +7.814s	91.2%qual 106.8%	2:06.997Peter Shadowen · fastest of 19 · top 5 within 4.0s	2:07.837Bill Ball · fastest of 18 · top 5 within 4.2s	131.1Peter Shadowen	-7.979squal +11.873s	94.1%qual 110.3%
17 rule changes (AS: 4, GTL: 13)5 cars added · 5 weight · 2 engine · 2 suspension & brakes · 1 induction · 1 tyres & wheels · 1 othershowhide 2019-10-01 AS Request to add SMG to 9.1.6.B.1 AS Intent #27140other 2019-08-31 GTL Fun Cup Beetle #27334weight 2019-08-01 AS Request Ride Height Clarification #26598suspension & brakes 2019-08-01 GTL GTL #26960weight 2019-07-01 GTL Request CRZ wheelbase change #26896tyres & wheels 2019-05-31 AS Request to Revert to 2017 Weights #25885weight 2019-05-01 GTL Request to Classify VW Fun Cup Beetle #25986cars added 2019-05-01 GTL Request GTX Fuel injection for previous GT-1 tube frame cars #26141engine 2019-05-01 GTL Request to Classify Ligier JS2 R #26535cars added 2019-05-01 GTL Request for GTL Mazda 13B SIR Increase with Penalty #26572engine 2019-04-01 GTL Request Ride Height Clarification #26600suspension & brakes 2019-03-01 GTL Request Mazda 12a Rotary SIR Increase #26081induction 2019-03-01 GTL Request to Classify Mustang 2 Body in GTL #26222cars added 2019-02-01 AS SMG Mustang eligibility in American sedan #26224cars added 2019-01-01 GTL Request for GTL Mini Adjustments #25754weight 2019-01-01 GTL BMC thru Rover Group remove long inactive mini #25771weight 2019-01-01 GTL GTX Homologation table update #26034cars added
	Sonoma Raceway Runoffs 20182018-10-10	1:37.598Bryce Cornet · fastest of 13 · top 5 within 0.9s	1:37.909Bryce Cornet · fastest of 12 · top 5 within 1.3s	124.1Melvin David Kemper Jr	1:47.782Andrew McDermid · fastest of 12 · top 5 within 1.9s	1:50.345John Heinricy · fastest of 10 · top 5 within 2.3s	105.0Kevin Fandozzi	+12.436squal +10.184s	112.7%qual 110.4%	1:47.885Troy Ermish · fastest of 20 · top 5 within 4.5s	1:49.458Troy Ermish · fastest of 19 · top 5 within 3.6s	109.3Charles Leonard	+11.549squal +10.287s	111.8%qual 110.5%
No rule changes on record between these events
	Indianapolis Motor Speedway Runoffs 20172017-09-25	1:41.231Jarret Voorhies · fastest of 16 · top 5 within 1.7s	1:41.146Jarret Voorhies · fastest of 16 · top 5 within 1.2s		1:45.220James Jost · fastest of 29 · top 5 within 6.7s	1:51.507Bryan Long · fastest of 28 · top 5 within 0.9s		+10.361squal +3.989s	110.2%qual 103.9%	1:50.331Christopher Bovis · fastest of 26 · top 5 within 1.5s	1:52.068Christopher Bovis · fastest of 20 · top 5 within 1.0s		+10.922squal +9.100s	110.8%qual 109.0%
No rule changes on record between these events
	Mid-Ohio Sports Car Course Runoffs 20162016-09-19	1:26.043Jacob Loomis · fastest of 8 · top 5 within 3.1s	1:27.922Jacob Loomis · fastest of 8 · top 5 within 2.7s		1:30.651Tom Sloe · fastest of 22 · top 5 within 3.6s	1:33.424Edward Hosni · fastest of 20 · top 5 within 1.0s		+5.502squal +4.608s	106.3%qual 105.4%	1:35.377Wilson Wright · fastest of 28 · top 5 within 1.2s	1:35.912Kyle Disque · fastest of 28 · top 5 within 1.1s		+7.990squal +9.334s	109.1%qual 110.8%
No rule changes on record between these events
	Daytona International Speedway Runoffs 20152015-09-21	1:57.804Joseph Burton-Harris · fastest of 10 · top 5 within 2.3s	1:58.029Joseph Burton-Harris · fastest of 10 · top 5 within 1.7s		2:01.746Tom Sloe · fastest of 22 · top 5 within 2.6s	2:02.922Andy McDermid · fastest of 19 · top 5 within 2.2s		+4.893squal +3.942s	104.1%qual 103.3%	2:11.387Jim Dentici · fastest of 10 · top 5 within 2.2s	2:13.564Jim Dentici · fastest of 9 · top 5 within 2.0s		+15.535squal +13.583s	113.2%qual 111.5%

By track

Track	Events	Typical % of FM	Best	Latest
Road America	4	0 of 4 with FM
Virginia International Raceway	3	100.0%1 of 3 with FM	100.0%Runoffs 2019	100.0%Runoffs 2019
Indianapolis Motor Speedway	2	100.0%1 of 2 with FM	100.0%Runoffs 2017	100.0%Runoffs 2017
Daytona International Speedway	1	100.0%	100.0%Runoffs 2015	100.0%Runoffs 2015
Mid-Ohio Sports Car Course	1	100.0%	100.0%Runoffs 2016	100.0%Runoffs 2016
Sonoma Raceway	1	100.0%	100.0%Runoffs 2018	100.0%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 FM'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.