BoP Lab / Classes / STL

STL vs FC pace at every track

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

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AS +B-Spec +EP +FA +vsFC ×FE2 +FF +FP +FV +FX +GT1 +GT2 +GTX +HP +P +P2 +SM +SMX +SRF3 +STL×STU +T1 +T2 +T3 +T4 +Show 51 inactive classes

Series Runoffs Super Tour Both

Reference · what % is measured against, 12 events

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: STL 100.0% of STL Kevin Boehm, Daytona International Speedway Runoffs 2015 race · FC 79.0% of STL Simon Sikes, Indianapolis Motor Speedway Runoffs 2021 race

% of STLLap times

STLFCsolid race · dashed qualifying · slower is lower

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

	Event	STL			FC
	Event	Qual best	Race best	Trap	Qual best	Race best	Trap	vs STL	% of STL
	Road America Runoffs 20262026-09-28	2:30.537Derek Ketchie · fastest of 16 · top 5 within 2.9s-1.528s (-1.00%)	2:30.657Danny Steyn · fastest of 16 · top 5 within 0.6s-1.470s (-0.97%)	134.8Mike Taylor+2.6 mph (+2.0%)	2:10.686Brandon Dixon · fastest of 10 · top 5 within 4.0s-0.573s (-0.44%)	2:11.389Brandon Dixon · fastest of 10 · top 5 within 2.7s-1.435s (-1.08%)	143.3Dean Kiriluk-1.8 mph (-1.2%)	-19.268squal -19.851s	87.2%qual 86.8%
6 rule changes (STL: 4, FC: 2)4 weight · 1 removed · 1 othershowhide 2026-07-01 STL Spec Line Clean Up #40344removed 2026-06-01 STL Calculating Weight #40224weight 2026-04-01 STL Classifications #39885weight 2026-01-01 FC F2000 MZR Spec Line Clarity/Revision Requested #38927other 2026-01-01 FC Adjust F2000 Metrik ZF2 weight #39612weight -20 lbs 2026-01-01 STL Weight adjustment for STL #39579weight
	Road America Runoffs 20252025-09-29	2:32.065Jose Osiris Pena · fastest of 14 · top 5 within 3.4s+2.002s (+1.33%)	2:32.127Jose Osiris Pena · fastest of 13 · top 5 within 2.4s+1.882s (+1.25%)	132.2Jon Sewell-2.1 mph (-1.5%)	2:11.259Brandon Dixon · fastest of 10 · top 5 within 2.7s-0.367s (-0.28%)	2:12.824Brandon Dixon · fastest of 9 · top 5 within 2.3s+1.290s (+0.98%)	145.1Brandon Dixon+0.9 mph (+0.6%)	-19.303squal -20.806s	87.3%qual 86.3%
5 rule changes (STL: 3, FC: 2)3 weight · 2 tyres & wheelsshowhide 2025-08-01 STL Lotus Weight Reduction #38772weight -50 lbs 2025-05-01 STL E&O: SMX Allowance in STL #37945weight 2024-12-01 STL Request to Remove Miata Hubs from General category #37138tyres & wheels 2024-11-01 FC 9.1.1.10.h. FC Tire Rule #36533tyres & wheels 2024-11-01 FC Change FF/FC Weight with Sequential Gearbox #36651weight
	Road America Runoffs 20242024-10-01	2:30.063Joe Moser · fastest of 18 · top 5 within 3.7s-1.357s (-0.90%)	2:30.245Joe Moser · fastest of 16 · top 5 within 4.2s-1.870s (-1.23%)	134.3Joe Moser+1.3 mph (+1.0%)	2:11.626Timothy Minor · fastest of 10 · top 5 within 1.3s-1.018s (-0.77%)	2:11.534Michael Varacins · fastest of 9 · top 5 within 1.8s-2.074s (-1.55%)	144.2Michael Varacins+1.8 mph (+1.2%)	-18.711squal -18.437s	87.5%qual 87.7%
6 rule changes (STL: 4, FC: 2)3 weight · 2 induction · 1 othershowhide 2024-04-01 FC Four Pot Calipers #35481weight 2024-02-01 STL ST Electric-Assisted Steering Systems #35066other 2024-02-01 STL BOP Adjustments #35112weight 2024-02-01 STL Mazda 12A #35320induction 2024-01-01 FC Please correct omitted punctuation #34890weight 2024-01-01 STL Alternate Carburetor Request for 79-85 RX7 12a #35181induction
	Virginia International Raceway Runoffs 20232023-09-23	2:05.779Danny Steyn · fastest of 22 · top 5 within 3.4s+0.305s (+0.24%)	2:06.682Joe Moser · fastest of 20 · top 5 within 1.5s-1.150s (-0.90%)	131.8Danny Steyn+0.1 mph (+0.1%)	1:50.281Nolan Allaer · fastest of 11 · top 5 within 2.3s+0.386s (+0.35%)	1:51.169Nolan Allaer · fastest of 11 · top 5 within 2.5s-16.690s (-13.05%)	143.5Robert Allaer+2.3 mph (+1.7%)	-15.513squal -15.498s	87.8%qual 87.7%
5 rule changes (STL: 2, FC: 3)3 tyres & wheels · 1 engine · 1 weightshowhide 2023-07-01 FC Review FC Runoffs Tire Marking Rule #34274tyres & wheels 2023-06-01 FC USF2000 Van Diemen with Mazda MZR LF-DE 2.0L in FC #34329weight 2023-06-01 STL Clarify STL table B - IT spec notes on Tires #34187tyres & wheels 2023-01-01 FC E&O 9.1.1.B.16.j #33634engine 2023-01-01 STL Spec MX5 in STL #33473tyres & wheels
	Virginia International Raceway Runoffs 20222022-09-24	2:05.474Danny Steyn · fastest of 24 · top 5 within 2.3s-1.729s (-1.36%)	2:07.832Danny Steyn · fastest of 22 · top 5 within 1.9s+0.559s (+0.44%)	131.7Trever Degioanni-3.2 mph (-2.3%)	1:49.895Nolan Allaer · fastest of 12 · top 5 within 1.5s-1.305s (-1.17%)	2:07.859Nolan Allaer · fastest of 13 · top 5 within 3.8s+15.685s (+13.98%)	141.2Tim Minor-0.6 mph (-0.4%)	+0.027squal -15.579s	100.0%qual 87.6%
10 rule changes (STL: 5, FC: 5)3 engine · 2 induction · 2 tyres & wheels · 1 weight · 2 wordingshowhide 2022-07-01 FC Add Specification to Performance Electronics ECU for Ford Zetec #32761engine 2022-03-01 STL Single TB Weight Modifiers #31449weight 2022-03-01 STL Improved Touring Tires #32063tyres & wheels 2022-01-01 FC Clean up Chassis/Frame section #31867engine 2022-01-01 STL Throttling Device Clarification #31323induction 2022-01-01 STL Mazda Renesis Restriction #31467induction 2022-01-01 STL Clarification of 79-85 RX7 Spec line #31621wording 2021-12-01 FC Clarify Zetec ECU requirements #31554engine 2021-11-01 FC Clarify composite anti-intrusion panel language #31426wording 2021-11-01 FC Clarify tire marking requirements #31455tyres & wheels
	Indianapolis Motor Speedway Runoffs 20212021-09-25	1:51.665Danny Steyn · fastest of 42 · top 5 within 1.7s-0.982s (-0.87%)	2:02.711Joe Moser · fastest of 37 · top 5 within 3.2s+10.122s (+8.99%)	131.8Max Gee	1:36.787Trent Walko · fastest of 31 · top 5 within 1.7s+0.451s (+0.47%)	1:36.980Simon Sikes · fastest of 31 · top 5 within 2.0s+0.090s (+0.09%)	141.6Tim Minor	-25.731squal -14.878s	79.0%qual 86.7%
16 rule changes (STL: 15, FC: 1)3 weight · 2 aero · 2 engine · 2 induction · 2 suspension & brakes · 1 cars added · 1 tyres & wheels · 1 wording · 2 othershowhide 2021-09-01 STL Request to clean up Spec MX-5 Redundancy #31069other 2021-06-01 STL VW Engine Request #30625engine 2021-05-01 STL Solstice Ride Height #30183suspension & brakes 2021-05-01 STL Request Mazda B5 DOHC #30420cars added 2021-05-01 STL Honda B16A (JDM) Restrictor change #30531induction 2021-04-01 STL ST Oil Coolers E&O Correction to 9.1.4.2.H #30388wording 2021-03-01 FC Request for FC Weight Change #30171weight 2021-03-01 STL GM Ecotec engines in STL #30247engine 2021-03-01 STL Super Touring Alternate Miata Hubs #30345tyres & wheels 2021-02-01 STL Brake Component Relocation #29990suspension & brakes 2021-02-01 STL Super Touring Wing Clarification #30111aero 2021-02-01 STL Transmission Options #30118other 2021-01-01 STL Request for FWD and RWD Parity #29728weight 2021-01-01 STL Request to Remove Honda F20C 2% Weight Penalty #29815weight 2021-01-01 STL Request for FWD and RWD Parity #30023induction 2020-12-01 STL Request clarification on wing measurement #29640aero
	Road America Runoffs 20202020-10-02	2:31.420Danny Steyn · fastest of 33 · top 5 within 3.1s	2:32.115Joe Moser · fastest of 30 · top 5 within 1.5s	132.9Darin Treakle	2:12.644Robert Allaer · fastest of 13 · top 5 within 2.1s	2:13.608Robert Allaer · fastest of 11 · top 5 within 1.2s	142.4Robert Allaer	-18.507squal -18.776s	87.8%qual 87.6%
15 rule changes (STL: 11, FC: 4)5 induction · 4 engine · 2 weight · 1 aero · 1 cars added · 1 tyres & wheels · 1 wordingshowhide 2020-10-01 FC Urgent: SCCA PE3 map unsuitable #29475induction 2020-08-01 FC Request for weight adjustments to equalize FC competition. #28888weight 2020-08-01 STL Minimum Weight Determination #27695weight 2020-08-01 STL ST Gurney flap Wicker clarification #29012aero 2020-07-01 STL Request for Addition to GT3 Approved Turbo List #27576induction 2020-06-01 STL Request to add 2016-2019 GMX-5 Spec line #28604cars added 2020-06-01 STL Request to update PN for MX-5 #28622wording 2020-06-01 STL Correction - Clarification Honda/Acura B18B engine Letter # 26209 #28873engine 2020-05-01 STL STL Honda B18 restrictor changes #28794induction 2020-04-01 STL Change GM LNF 2.0 Allowance to LSJ Engine for Viable STL 2.0 #27884engine 2020-04-01 STL Acura/Honda B18C engine chart. Reduce the current 54 mm flat plat #28663induction 2020-04-01 STL Mazda MZR engine chart. Reduce the current 55 mm flat plate to 53 #28664induction 2020-03-01 STL Request to add wheel part numbers #28342tyres & wheels 2019-12-01 FC Request for Better Zetec Connecting Rods #27710engine 2019-12-01 FC Add Alternate Piston #27795engine
	Virginia International Raceway Runoffs 20192019-10-05	2:07.203Danny Steyn · fastest of 36 · top 5 within 1.8s	2:07.273Cliff Ira · fastest of 35 · top 5 within 1.4s	134.8Cliff Ira	1:51.200Robert Allaer · fastest of 10 · top 5 within 3.1s	1:52.174Robert Allaer · fastest of 9 · top 5 within 2.7s	141.8Robert Allaer	-15.099squal -16.003s	88.1%qual 87.4%
13 rule changes (STL: 11, FC: 2)6 weight · 2 induction · 2 suspension & brakes · 1 cars added · 1 engine · 1 wordingshowhide 2019-10-01 STL Request to Classify Spec MX-5 Challenge in STL #27399cars added 2019-07-01 STL Request clarification for manifold and throttle in STU #27004induction 2019-05-31 STL Request Restrictor Plate correction #26779induction 2019-05-01 FC E&O Wiseco piston and Crower connecting rod #26659weight 2019-05-01 STL Request Ride Height Clarification #26597suspension & brakes 2019-03-01 STL Request to Allow VW 1.8L Engine #25614engine 2019-03-01 STL Request to reduce weight of RX8 with Renesis rotary #25781weight -100 lbs 2019-03-01 STL Request for Open Brake Pads On Mazda MX-5 Cup NC #25821suspension & brakes 2019-03-01 STL Request to clarify B18C1 GSR Honda B motor table #26209weight 2019-03-01 STL Port Matching #26415wording 2019-01-01 FC Correct Wiseco piston and connecting rod #25809weight 2019-01-01 STL Request to equalize FPR Reduction on all B-Series Vtec Engines #24746weight 2019-01-01 STL Request E&O for Mazda Miata Spec Line #25955weight
	Sonoma Raceway Runoffs 20182018-10-10	1:49.138Danny Steyn · fastest of 19 · top 5 within 2.5s	1:49.754Danny Steyn · fastest of 17 · top 5 within 2.5s	103.2Craig McHaffie	1:32.571Timothy de Silva · fastest of 16 · top 5 within 1.8s	1:34.053Mitch Egner · fastest of 12 · top 5 within 1.6s	133.1Robert Armington	-15.701squal -16.567s	85.7%qual 84.8%
No rule changes on record between these events
	Indianapolis Motor Speedway Runoffs 20172017-09-25	1:52.647Adam Roberts · fastest of 57 · top 5 within 0.8s	1:52.589Eric Kutil · fastest of 50 · top 5 within 1.2s		1:36.336Austin McCusker · fastest of 14 · top 5 within 2.3s	1:36.890Tim Minor · fastest of 14 · top 5 within 3.8s		-15.699squal -16.311s	86.1%qual 85.5%
No rule changes on record between these events
	Mid-Ohio Sports Car Course Runoffs 20162016-09-19	1:35.439John Schmitt · fastest of 34 · top 5 within 1.5s	1:36.625Kevin Boehm · fastest of 31 · top 5 within 0.6s		1:21.962John LaRue · fastest of 7 · top 5 within 2.6s	1:22.049Nigel Saurino · fastest of 7 · top 5 within 3.0s		-14.576squal -13.477s	84.9%qual 85.9%
No rule changes on record between these events
	Daytona International Speedway Runoffs 20152015-09-21	2:09.672Kevin Boehm · fastest of 37 · top 5 within 2.5s	2:10.269Kevin Boehm · fastest of 37 · top 5 within 2.1s		1:54.477Yufeng Luo · fastest of 11 · top 5 within 2.5s	1:55.135Yufeng Luo · fastest of 10 · top 5 within 2.1s		-15.134squal -15.195s	88.4%qual 88.3%

By track

Track	Events	Typical % of STL	Best	Latest
Road America	4	100.0%	100.0%Runoffs 2020	100.0%Runoffs 2026
Virginia International Raceway	3	100.0%	100.0%Runoffs 2019	100.0%Runoffs 2023
Indianapolis Motor Speedway	2	100.0%	100.0%Runoffs 2017	100.0%Runoffs 2021
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 STL's best on the same day: the weather and the day cancel out, so one figure compares across years where lap times cannot; a class that suits one track more than another still reads differently there. It still moves when the yardstick's own balance changes or its field thins, and an event the yardstick did not run has no point. A best from fewer than three cars is greyed. The rule changes that took effect between two events are folded between their rows.