BoP Lab / Classes / F6

F6 vs FM vs SRF vs FA pace at every track

Lap times across years say as much about the weather as the class. % of F6 is each class's best lap as a share of F6'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-SpecEPF6×vsFA ×FCFE2FFvsFM ×FPFVFXGT1GT2GTXHPPP2SMSMXvsSRF ×SRF3STLSTUT1T2T3T4Show 48 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: F6 100.0% of F6 Calvin Stewart, Virginia International Raceway Runoffs 2023 race · FA 87.4% of F6 Hans Peter, Road America Runoffs 2024 qualifying

% of F6Lap times

F6FMSRFFAsolid race · dashed qualifying · slower is lower

F6FMSRFFAsolid race · dashed qualifying · each class's best lap as a share of F6's at the same event (the reference class, changeable above); 100% is level, less is quicker, so up the chart is quicker

	Event	F6			FM					SRF					FA
	Event	Qual best	Race best	Trap	Qual best	Race best	Trap	vs F6	% of F6	Qual best	Race best	Trap	vs F6	% of F6	Qual best	Race best	Trap	vs F6	% of F6
	Road America Runoffs 20262026-09-28	2:18.489Calvin Stewart · fastest of 13 · top 5 within 4.2s-0.617s (-0.44%)	2:20.255James Weida · fastest of 13 · top 5 within 2.0s+1.415s (+1.02%)	143.0Calvin Stewart-4.5 mph (-3.1%)											2:02.513Dudley Fleck · fastest of 9 · top 5 within 6.9s+1.590s (+1.31%)	2:03.334James French · fastest of 10 · top 5 within 1.4s+0.680s (+0.55%)	158.6John McAleer+1.5 mph (+1.0%)	-16.921squal -15.976s	87.9%qual 88.5%
10 rule changes (SRF: 3, FA: 7)3 induction · 2 engine · 1 suspension & brakes · 1 weight · 3 othershowhide 2026-09-01 SRF GCR Rain/Brake Light Correction #40579suspension & brakes 2026-08-01 FA Update sealed engine teardown section #40621engine 2026-06-01 FA Motor Classification #40175weight 2026-03-01 SRF SRF3 Spark Plugs #39899other 2026-02-01 FA Pro Mazda Classification and Performance Enhancement Proposal #39411induction 2026-01-01 FA Alternate Intake Manifold for MZR #38223induction 2026-01-01 FA Engine Compression Rule Change Request #39302engine 2026-01-01 FA Change Formula 1000 allowances #39608induction 2025-11-01 FA Re-Consider USF Pro 2000 Car for Formula Atlantic Class #38783other 2025-10-01 SRF Add HD Oil Cooler #38979other
	Road America Runoffs 20252025-09-29														2:00.923Hans Peter · fastest of 12 · top 5 within 2.4s-0.637s (-0.52%)	2:02.654Hans Peter · fastest of 11 · top 5 within 3.1s+0.864s (+0.71%)	157.0Shane Kennett-3.0 mph (-1.9%)
5 rule changes (SRF: 2, FA: 3)2 tyres & wheels · 1 cars added · 2 othershowhide 2025-07-01 FA Ligier JS F3 Tire Choice #38434tyres & wheels 2025-04-01 SRF Driver Safety & Comfort #37966other 2025-04-01 SRF Update SADEV transmission specs #37992other 2025-03-01 FA Update Formula Renault 2.0 spec line notes #37853tyres & wheels 2025-02-01 FA Classify FR European Championship car as spec line car in Table 2 #37658cars added
	Road America Runoffs 20242024-10-01	2:19.106Calvin Stewart · fastest of 22 · top 5 within 1.3s	2:18.840James Weida · fastest of 22 · top 5 within 1.0s	147.6Calvin Stewart											2:01.560Hans Peter · fastest of 13 · top 5 within 2.0s-2.714s (-2.18%)	2:01.790Dudley Fleck · fastest of 12 · top 5 within 3.3s-2.956s (-2.37%)	160.0Brandon Schwarz+9.4 mph (+6.3%)	-17.050squal -17.546s	87.7%qual 87.4%
10 rule changes (SRF: 10)3 suspension & brakes · 3 tyres & wheels · 1 weight · 1 wording · 2 othershowhide 2024-10-01 SRF Update SRF3 Air Filter Rule #36681other 2024-10-01 SRF Update SRF Brake Rotor Thickness #36687suspension & brakes 2024-10-01 SRF Hoosier Tire Decal Placement #36739tyres & wheels 2024-09-01 SRF Protest Fee Clarification #36540wording 2024-09-01 SRF Update to Letter 36619 with new Hoosier Contingency Decal Info #36624tyres & wheels 2024-08-01 SRF Update Rain Tire Rule and Hoosier Decal Placement #36436tyres & wheels 2024-01-01 SRF Update SRF Rain / Brake Rule #34706suspension & brakes 2024-01-01 SRF Update SRF Brake Light Rule v1 #34853suspension & brakes 2024-01-01 SRF SRF / SRF3 Rule Updates #35268weight 2023-10-01 SRF SRF Radiator Rule Update #34805other
	Virginia International Raceway Runoffs 20232023-09-23	1:57.437Calvin Stewart · fastest of 9 · top 5 within 4.7s	1:58.816Calvin Stewart · fastest of 9 · top 5 within 3.6s	144.0Calvin Stewart
10 rule changes (SRF: 3, FA: 7)4 tyres & wheels · 2 induction · 1 engine · 1 suspension & brakes · 1 weight · 1 othershowhide 2023-06-01 FA Simplify Pro Formula Mazda wheel allowance #34190tyres & wheels 2023-06-01 SRF Hoosier SRF Wet Front Tire Rule Update #34189tyres & wheels 2023-05-01 FA E&O - Correct Pro Formula Mazda spec line dimensional equivalent #34085tyres & wheels 2023-05-01 FA Add new spec line for MSR Formula Mazda FMzR to Table 2 #34139other 2023-05-01 SRF Update SRF Front W2 Rain Tire Part Number #34118tyres & wheels 2023-03-01 SRF Update SRF Brake Rule #33469suspension & brakes 2023-01-01 FA BDA Displacement #33431engine 2022-12-01 FA Reclassify 2010-2017 Formula Renault 2.0 as a spec line car in FA #33395weight 2022-12-01 FA Change Swift 016 2.3L restrictor size and minimum weight #33472induction -30 lbs 2022-10-01 FA Pro Formula Mazda Dimension E&O #33160induction
	Virginia International Raceway Runoffs 20222022-09-24														1:44.703Chip Romer · fastest of 7 · top 5 within 4.0s+3.158s (+3.11%)	1:48.507Alex Mayer · fastest of 4 · top 4 within 4.2s+5.400s (+5.24%)	154.6Austin Hill-1.4 mph (-0.9%)
10 rule changes (SRF: 3, FA: 7)3 engine · 2 tyres & wheels · 2 weight · 1 aero · 1 suspension & brakes · 1 othershowhide 2022-06-01 SRF SRF Tire Rule Update #32614tyres & wheels 2022-06-01 SRF Brake, seal, and air filter clarifications #32670suspension & brakes 2022-05-01 FA Update FR Americas rulebook requirement #32491engine 2022-05-01 FA Clarify verification of sealed engine compliance #32522engine 2022-05-01 FA Clarify Formula Lites and FR Americas sealed engine requirement #32523engine 2022-04-01 FA E&O FA Transmission section #32251tyres & wheels 2022-04-01 FA E&O Swift 016 2.5 liter Aero column #32363aero 2022-03-01 FA Closing the Gap #31934other 2022-02-01 FA Reorganize Tables 1 and 2 #31985weight 2021-12-01 SRF Three Updates to SRF Rules #31523weight
	Indianapolis Motor Speedway Runoffs 20212021-09-25														1:29.701James French · fastest of 18 · top 5 within 2.7s-0.256s (-0.28%)	1:30.650James French · fastest of 17 · top 5 within 6.1s-0.715s (-0.78%)	155.5James French
28 rule changes (SRF: 6, FA: 22)8 engine · 7 weight · 2 induction · 2 removed · 2 tyres & wheels · 1 cars added · 1 suspension & brakes · 1 wording · 4 othershowhide 2021-09-01 FA E&O Table 2 engine names #31085engine 2021-08-01 FA Move Toyota 1800 to Table 2 #30822removed 2021-08-01 FA E&O Swift 016 wheel width reference #30939tyres & wheels 2021-08-01 SRF SRF Wet Tires #30849tyres & wheels 2021-08-01 SRF SADEV-SRF3 Transmission #30926other 2021-08-01 SRF SRF Update Maintenance, Repairs and Seals #30961engine 2021-07-01 FA Update FA rules package #30717engine 2021-07-01 FA Move Mazda MZR/Ford Duratec 2296cc and 2500cc to Table 2 #30718removed 2021-07-01 FA Clean up Table 2 Mazda MZR 2.0L and Honda Civic K20Z3 spec lines #30719other 2021-06-01 FA E&O Mazda MZR 2.0 and Honda Civic K20Z3 chassis eligibility #30632other 2021-06-01 SRF SRF3 Alternator Pulley #30684weight 2021-05-01 FA Correct engine name in Swift 016 2.3 liter spec line #30447engine 2021-05-01 FA Correct engine name in Swift 016 2.5 liter spec line #30448engine 2021-05-01 FA Revise Table 1 Spec Lines and clarify application of Engine Notes #30456engine 2021-04-01 FA Update Table 1 Weights for Spec Lines C, I, and K #30355weight -25 lbs 2021-04-01 FA Remove redundant reference in Table 2 spec line #30366weight 2021-04-01 FA Correct the name of the FR Americas car #30369wording 2021-04-01 FA Clean up Spec Line D in Table 1 #30372weight 2021-04-01 FA Table 2 Honda K20Z3 request #30386induction 2021-03-01 FA E&O FA Intake Restrictors #30273induction 2021-03-01 FA Clean up Spec Lines A and B in Table 1 #30274weight 2021-03-01 FA Clean up Spec Line C in Table 1 #30275weight 2021-03-01 FA Clean up Spec Lines J and L in Table 1 #30276weight 2021-03-01 FA Move engine specifications to Pro Formula Mazda spec line notes #30278engine 2021-03-01 FA Update F3 Americas spec line #30280other 2021-03-01 SRF Mandatory identification: #30223engine 2021-01-01 FA Request to classify Formula Lites Crawford FL15 #29702cars added 2020-12-01 SRF SRF Shocks, Springs and Ride Height. #29688suspension & brakes
	Road America Runoffs 20202020-10-02														2:04.274Spencer Brockman · fastest of 11 · top 5 within 2.7s	2:04.746Spencer Brockman · fastest of 10 · top 5 within 2.4s	150.6Hans Peter
20 rule changes (SRF: 5, FA: 15)4 engine · 3 tyres & wheels · 3 weight · 2 induction · 2 suspension & brakes · 1 aero · 1 removed · 4 othershowhide 2020-07-01 FA Request to Adjust FB Weight for Stock Engines #29005weight 2020-06-01 FA E&O permitted engine modifications #28831engine 2020-06-01 FA E&O Transmissions #28832other 2020-06-01 FA Swift 016 Gurney flap wicker clarification #28884aero 2020-05-01 FA Remove redundant spec line in Table 1 #28720removed 2020-05-01 FA E&O general engine rules #28772engine 2020-05-01 SRF SRF Bump Stop Correction #27019suspension & brakes 2020-04-01 FA Request higher compression ratio and prior weights for F1000 cars #28162engine 2020-04-01 FA Remove redundant wheel dimension provisions #28554tyres & wheels 2020-04-01 FA E&O Formula 3 spec line #28596induction 2020-03-01 FA FA weight correction/clarification #28430engine 2020-01-01 FA Request to merge FB into FA #25611weight 2020-01-01 FA Suggestions for FB/F1000 into FA #27319other 2020-01-01 FA Change Swift 016 - 2.3 liter Mazda Duratec restrictor size #27880induction 202-01-01 SRF SRF Rain / Brake Rule - BoD approved as follows #34958suspension & brakes 2019-12-01 FA Move wheel dimensions from Bodywork subsection to #27493tyres & wheels 2019-12-01 FA Table 2 Mazda MZR 2.0 E&O #27640other 2019-12-01 SRF SRF Tire Warmer Rule #27622tyres & wheels 2019-12-01 SRF SRF / SRF3 Nose Weight Reduction #27706weight 2019-12-01 SRF SRF / SRF3 Majors & Regional Class Updates #27723other
	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								1:41.545Dario Cangialosi · fastest of 8 · top 5 within 2.8s	1:43.107Dario Cangialosi · fastest of 8 · top 5 within 1.8s	155.9Kent Vaccaro
8 rule changes (SRF: 1, FA: 7)3 weight · 2 engine · 1 removed · 2 othershowhide 2019-10-01 FA Follow up to Letter #27344 on Honda Powered FA Rules #27363removed 2019-08-31 FA Swift 014 Mazda MZR 2.0 E&O #27305weight 2019-07-01 SRF SRF Dash Windscreen Kit #27028other 2019-05-31 FA Adjust Line N restrictor size and minimum weight #26691weight +30 lbs 2019-05-01 FA Add data plate requirement #26707other 2019-03-01 FA Request to add FA engine spec lines #26183engine 2019-02-01 FA FA MZR 2.0 Engine Specification #25814engine 2019-02-01 FA FA 016 weight increase #26063weight
	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								1:28.176Mirl Swan · fastest of 7 · top 5 within 4.0s	1:29.924Mirl Swan · fastest of 7 · top 5 within 2.6s	144.8Antony Opheim
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				1:51.573Thomas Kirchman · fastest of 50 · top 5 within 2.8s	1:53.769Todd Harris · fastest of 45 · top 5 within 0.2s				1:29.957Sedat Yelkin · fastest of 12 · top 5 within 2.3s	1:31.365Keith Grant · fastest of 12 · top 5 within 1.0s
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				1:37.344Mike Miserendino · fastest of 27 · top 5 within 0.8s	1:37.621Todd Harris · fastest of 27 · top 5 within 0.6s				1:14.920Ryan Norman · fastest of 5 · top 5 within 7.0s	1:19.009Ryan Norman · fastest of 5 · top 5 within 4.7s
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				2:14.306Cliff White · fastest of 39 · top 5 within 1.2s	2:16.700Cliff White · fastest of 38 · top 5 within 0.5s				1:47.758Tyler Hunter · fastest of 10 · top 5 within 3.7s	1:48.162Tyler Hunter · fastest of 8 · top 5 within 5.3s

By track

Track	Events	Typical % of F6	Best	Latest
Road America	4	100.0%2 of 4 with F6	100.0%Runoffs 2024	100.0%Runoffs 2026
Virginia International Raceway	3	100.0%1 of 3 with F6	100.0%Runoffs 2023	100.0%Runoffs 2023
Indianapolis Motor Speedway	2	0 of 2 with F6
Daytona International Speedway	1	0 of 1 with F6
Mid-Ohio Sports Car Course	1	0 of 1 with F6
Sonoma Raceway	1	0 of 1 with F6

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 F6'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.