BoP Lab / Classes / SRF

SRF vs FF pace at every track

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

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AS +B-Spec +EP +FA +FC +FE2 +vsFF ×FP +FV +FX +GT1 +GT2 +GTX +HP +P +P2 +SM +SMX +SRF×SRF3 +STL +STU +T1 +T2 +T3 +T4 +Show 50 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: SRF 100.0% of SRF Cliff White, Daytona International Speedway Runoffs 2015 race · FF 90.3% of SRF Rick Payne, Daytona International Speedway Runoffs 2015 race

% of SRFLap times

SRFFFsolid race · dashed qualifying · slower is lower

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

	Event	SRF			FF
	Event	Qual best	Race best	Trap	Qual best	Race best	Trap	vs SRF	% of SRF
	Road America Runoffs 20262026-09-28				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%)
5 rule changes (SRF: 3, FF: 2)1 engine · 1 suspension & brakes · 1 tyres & wheels · 2 othershowhide 2026-09-01 SRF GCR Rain/Brake Light Correction #40579suspension & brakes 2026-07-01 FF Clarification in FF Kent 1600 Compression Ratio Paragraph #40293engine 2026-03-01 SRF SRF3 Spark Plugs #39899other 2026-01-01 FF Formula F Alternative Tire Rule Proposed Clarifications #39281tyres & wheels 2025-10-01 SRF Add HD Oil Cooler #38979other
	Road America Runoffs 20252025-09-29				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%)
6 rule changes (SRF: 2, FF: 4)2 tyres & wheels · 2 weight · 2 othershowhide 2025-05-01 FF Page 228, FF tire rule 9.1.1.10.e #38251tyres & wheels 2025-04-01 SRF Driver Safety & Comfort #37966other 2025-04-01 SRF Update SADEV transmission specs #37992other 2025-03-01 FF Formula F Proposal to Invite Older Cars Via a Tire Rule Change #37802tyres & wheels 2024-11-01 FF Change FF/FC Weight with Sequential Gearbox #36651weight 2024-11-01 FF Alternative Oversize Honda Fit Pistons #37064weight
	Road America Runoffs 20242024-10-01				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%)
12 rule changes (SRF: 10, FF: 2)3 suspension & brakes · 3 tyres & wheels · 1 engine · 1 weight · 1 wording · 3 othershowhide 2024-10-01 FF Update to FF EGR Blanking Plate Rule #36633engine 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 FF Honda Fit Oversize Piston Rings #35305other 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				1:59.249Nolan 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%)
4 rule changes (SRF: 3, FF: 1)2 tyres & wheels · 1 engine · 1 suspension & brakesshowhide 2023-06-01 SRF Hoosier SRF Wet Front Tire Rule Update #34189tyres & wheels 2023-05-01 SRF Update SRF Front W2 Rain Tire Part Number #34118tyres & wheels 2023-03-01 FF Add Fast Forward Part Numbers for Honda Fit Engine #33752engine 2023-03-01 SRF Update SRF Brake Rule #33469suspension & brakes
	Virginia International Raceway Runoffs 20222022-09-24				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%)
3 rule changes (SRF: 3)1 suspension & brakes · 1 tyres & wheels · 1 weightshowhide 2022-06-01 SRF SRF Tire Rule Update #32614tyres & wheels 2022-06-01 SRF Brake, seal, and air filter clarifications #32670suspension & brakes 2021-12-01 SRF Three Updates to SRF Rules #31523weight
	Indianapolis Motor Speedway Runoffs 20212021-09-25				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
9 rule changes (SRF: 6, FF: 3)4 engine · 1 suspension & brakes · 1 tyres & wheels · 1 weight · 1 wording · 1 othershowhide 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 2021-06-01 SRF SRF3 Alternator Pulley #30684weight 2021-04-01 FF Kent crankshaft clarification #30426wording 2021-03-01 SRF Mandatory identification: #30223engine 2020-12-01 FF Allow Optional Coolant Bleed Line to Correct a Known Problem #29673engine 2020-12-01 FF Clarification regarding Honda LC1 ECU implementation date #29684engine 2020-12-01 SRF SRF Shocks, Springs and Ride Height. #29688suspension & brakes
	Road America Runoffs 20202020-10-02				2:22.916Simon Sikes · fastest of 14 · top 5 within 1.6s	2:24.268Jeffrey Bartz · fastest of 14 · top 5 within 0.4s	138.1Jeffrey Bartz
9 rule changes (SRF: 5, FF: 4)3 engine · 2 suspension & brakes · 2 tyres & wheels · 1 weight · 1 othershowhide 2020-08-01 FF Clarification regarding Honda LC1 ECU implementation #29135engine 2020-05-01 SRF SRF Bump Stop Correction #27019suspension & brakes 2020-04-01 FF E&O FF Kent Engine alternator language #28204engine 2020-03-01 FF Honda Racing HPD low cost ECU proposal #27563engine 2020-03-01 FF Update rain tire designation #28443tyres & wheels 202-01-01 SRF SRF Rain / Brake Rule - BoD approved as follows #34958suspension & brakes 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				1:59.563Tyler O'Connor · fastest of 14 · top 5 within 1.4s	2:20.474Jonathan Kotyk · fastest of 14 · top 5 within 6.3s	136.2Derek Ketchie
4 rule changes (SRF: 1, FF: 3)2 engine · 1 induction · 1 othershowhide 2019-07-01 SRF SRF Dash Windscreen Kit #27028other 2019-02-01 FF Request for Oversize Honda Fit Pistons #25810engine 2019-02-01 FF Heat Shield - Fit Intake #26102induction 2019-02-01 FF Request catch cans/tanks clarification #26158engine
	Sonoma Raceway Runoffs 20182018-10-10				1:41.612Jonathon Kotyk · fastest of 22 · top 5 within 1.7s	1:42.049Jonathon Kotyk · fastest of 22 · top 5 within 1.3s	115.7Denny Renfrow
No rule changes on record between these events
	Indianapolis Motor Speedway Runoffs 20172017-09-25	1:51.573Thomas Kirchman · fastest of 50 · top 5 within 2.8s	1:53.769Todd Harris · fastest of 45 · top 5 within 0.2s		1:44.601Zach Holden · fastest of 36 · top 5 within 1.2s	1:44.524Jonathon Kotyk · fastest of 36 · top 5 within 0.5s		-9.245squal -6.972s	91.9%qual 93.8%
No rule changes on record between these events
	Mid-Ohio Sports Car Course Runoffs 20162016-09-19	1:37.344Mike Miserendino · fastest of 27 · top 5 within 0.8s	1:37.621Todd Harris · fastest of 27 · top 5 within 0.6s		1:29.213Neil Verhagen · fastest of 14 · top 5 within 2.1s	1:30.133Neil Verhagen · fastest of 14 · top 5 within 1.4s		-7.488squal -8.131s	92.3%qual 91.6%
No rule changes on record between these events
	Daytona International Speedway Runoffs 20152015-09-21	2:14.306Cliff White · fastest of 39 · top 5 within 1.2s	2:16.700Cliff White · fastest of 38 · top 5 within 0.5s		2:02.489Tim Kautz · fastest of 25 · top 5 within 1.1s	2:03.383Rick Payne · fastest of 22 · top 5 within 0.8s		-13.317squal -11.817s	90.3%qual 91.2%

By track

Track	Events	Typical % of SRF	Best	Latest
Road America	4	0 of 4 with SRF
Virginia International Raceway	3	0 of 3 with SRF
Indianapolis Motor Speedway	2	100.0%1 of 2 with SRF	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	0 of 1 with SRF

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 SRF'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.