BoP Lab / Classes / STL

STL vs GTL vs SMX 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 +FC +FE2 +FF +FP +FV +FX +GT1 +GT2 +vsGTL ×GTX +HP +P +P2 +SM +vsSMX ×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: STL 100.0% of STL Kevin Boehm, Daytona International Speedway Runoffs 2015 race · GTL 91.2% of STL Scott Twomey, Indianapolis Motor Speedway Runoffs 2021 race · SMX 102.7% of STL Cam Ebben, Road America Runoffs 2025 qualifying

% of STLLap times

STLGTLSMXsolid race · dashed qualifying · slower is lower

STLGTLSMXsolid 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			GTL					SMX
	Event	Qual best	Race best	Trap	Qual best	Race best	Trap	vs STL	% of STL	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%)						2:36.472Skyler Cottrell · fastest of 21 · top 5 within 0.4s+0.240s (+0.15%)	2:36.414Cam Ebben · fastest of 21 · top 5 within 1.1s-0.677s (-0.43%)	128.4Christian Hoagland-0.6 mph (-0.5%)	+5.757squal +5.935s	103.8%qual 103.9%
7 rule changes (STL: 4, GTL: 1, SMX: 2)3 weight · 2 removed · 1 wording · 1 othershowhide 2026-07-01 SMX Rear Toe Link #40271other 2026-07-01 STL Spec Line Clean Up #40344removed 2026-06-01 STL Calculating Weight #40224weight 2026-04-01 SMX Part Number Change Request #39914wording 2026-04-01 STL Classifications #39885weight 2026-03-01 GTL Remove GT3U from GCR as it is now in STU #39862removed 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%)						2:36.232Cam Ebben · fastest of 20 · top 5 within 0.2s+0.581s (+0.37%)	2:37.091Michael Tinis · fastest of 19 · top 5 within 0.3s+0.813s (+0.52%)	129.1Camden Gruber-0.4 mph (-0.3%)	+4.964squal +4.167s	103.3%qual 102.7%
11 rule changes (STL: 3, GTL: 3, SMX: 5)3 weight · 2 tyres & wheels · 1 aero · 1 engine · 1 wording · 3 othershowhide 2025-08-01 STL Lotus Weight Reduction #38772weight -50 lbs 2025-06-01 SMX SMX Data Submission - Penalties #38248other 2025-06-01 SMX SMX Penaly Clarification updated language #38337wording 2025-05-01 SMX Clarify Tire Marking Regs #38004tyres & wheels 2025-05-01 SMX SMX Data Submission Timeframe #38039other 2025-05-01 STL E&O: SMX Allowance in STL #37945weight 2025-01-01 GTL Correct language regarding OEM Areo Devices #37137aero 2024-12-01 SMX E&O SMX Regs 9.1.7.1.D.5.u-.w #37070other 2024-12-01 STL Request to Remove Miata Hubs from General category #37138tyres & wheels 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	2:30.063Joe 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%)	2:30.858Peter 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%)	+0.599squal +0.795s	100.4%qual 100.5%	2:35.651Ethan Lampe · fastest of 23 · top 5 within 0.7s	2:36.278Ethan Jacobs · fastest of 22 · top 5 within 0.7s	129.5Michael Borden	+6.033squal +5.588s	104.0%qual 103.7%
24 rule changes (STL: 4, GTL: 16, SMX: 4)6 engine · 5 cars added · 4 induction · 4 weight · 1 aero · 1 suspension & brakes · 1 wording · 2 othershowhide 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 2024-09-01 SMX SMX Camera Rule Correction #36496wording 2024-09-01 SMX AIM ECU Protocol #36556engine 2024-09-01 SMX OE versus OEM Definitons #36608other 2024-09-01 SMX Shifter Bushing #36611suspension & brakes 2024-07-01 GTL Add GTL to GT3 choke option line. #36236induction 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 2024-02-01 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 2024-02-01 STL ST Electric-Assisted Steering Systems #35066other 2024-02-01 STL BOP Adjustments #35112weight 2024-02-01 STL Mazda 12A #35320induction 2024-01-01 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 2024-01-01 STL Alternate Carburetor Request for 79-85 RX7 12a #35181induction 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	2:05.779Danny 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%)	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%)	+4.595squal +3.785s	103.6%qual 103.0%	2:11.435Nathan Nicholson · fastest of 18 · top 5 within 0.6s	2:12.616Noah Harmon · fastest of 16 · top 5 within 0.1s	127.8Noah Harmon	+5.934squal +5.656s	104.7%qual 104.5%
9 rule changes (STL: 2, GTL: 7)3 engine · 2 tyres & wheels · 2 weight · 1 cars added · 1 inductionshowhide 2023-06-01 STL Clarify STL table B - IT spec notes on Tires #34187tyres & wheels 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 2023-01-01 STL Spec MX5 in STL #33473tyres & wheels 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	2:05.474Danny 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%)	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%)	+13.348squal +2.315s	110.4%qual 101.8%
8 rule changes (STL: 5, GTL: 3)2 cars added · 2 induction · 1 suspension & brakes · 1 tyres & wheels · 1 weight · 1 wordingshowhide 2022-09-01 GTL Tail lights on all GT category race cars. #32799suspension & brakes 2022-03-01 GTL Request to Classify Ginetta G40 in GTL #31599cars added 2022-03-01 STL Single TB Weight Modifiers #31449weight 2022-03-01 STL Improved Touring Tires #32063tyres & wheels 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 2021-10-01 GTL Request car classification #31032cars added
	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	1:51.819Christopher 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	-10.759squal +0.154s	91.2%qual 100.1%
23 rule changes (STL: 15, GTL: 8)4 weight · 3 engine · 3 induction · 2 aero · 2 cars added · 2 suspension & brakes · 2 tyres & wheels · 2 wording · 3 othershowhide 2021-09-01 STL Request to clean up Spec MX-5 Redundancy #31069other 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 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 GTL Request for Help for Mazda 12A #29754weight +50 lbs 2021-03-01 STL GM Ecotec engines in STL #30247engine 2021-03-01 STL Super Touring Alternate Miata Hubs #30345tyres & wheels 2021-02-01 GTL Request LP HP Fiat X1/9 & Bertone 1500 to GTL #30058cars added 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 GTL Please Add GTL Nissan 1.8L Engine MRA8DE #29805engine 2021-01-01 GTL Increase 13b SIR size #29867induction 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	2:31.943Chris Bovis · fastest of 14 · top 5 within 6.3s	2:31.601Peter Shadowen · fastest of 14 · top 5 within 7.2s	131.4Peter Shadowen	-0.514squal +0.523s	99.7%qual 100.3%
28 rule changes (STL: 11, GTL: 17)8 aero · 8 induction · 4 cars added · 3 weight · 2 engine · 1 tyres & wheels · 1 wording · 1 othershowhide 2020-09-01 GTL GT Category Wording #29193induction 2020-08-01 GTL Request to change the Mazda 13b restrictor size #28518induction +175 lbs 2020-08-01 STL Minimum Weight Determination #27695weight 2020-08-01 STL ST Gurney flap Wicker clarification #29012aero 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 2020-07-01 STL Request for Addition to GT3 Approved Turbo List #27576induction 2020-06-01 GTL Stall Test #28709induction 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 GTL GTL Wing Rule #28754aero 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 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 2020-03-01 STL Request to add wheel part numbers #28342tyres & wheels 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	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	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	+0.564squal -0.206s	100.4%qual 99.8%
24 rule changes (STL: 11, GTL: 13)8 weight · 5 cars added · 3 engine · 3 induction · 3 suspension & brakes · 1 tyres & wheels · 1 wordingshowhide 2019-10-01 STL Request to Classify Spec MX-5 Challenge in STL #27399cars added 2019-08-31 GTL Fun Cup Beetle #27334weight 2019-08-01 GTL GTL #26960weight 2019-07-01 GTL Request CRZ wheelbase change #26896tyres & wheels 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 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 2019-05-01 STL Request Ride Height Clarification #26597suspension & brakes 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 2019-03-01 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 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 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	1:47.885Troy Ermish · fastest of 20 · top 5 within 4.5s	1:49.458Troy Ermish · fastest of 19 · top 5 within 3.6s	109.3Charles Leonard	-0.296squal -1.253s	99.7%qual 98.9%
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		1:50.331Christopher Bovis · fastest of 26 · top 5 within 1.5s	1:52.068Christopher Bovis · fastest of 20 · top 5 within 1.0s		-0.521squal -2.316s	99.5%qual 97.9%
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		1:35.377Wilson Wright · fastest of 28 · top 5 within 1.2s	1:35.912Kyle Disque · fastest of 28 · top 5 within 1.1s		-0.713squal -0.062s	99.3%qual 99.9%
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		2:11.387Jim Dentici · fastest of 10 · top 5 within 2.2s	2:13.564Jim Dentici · fastest of 9 · top 5 within 2.0s		+3.295squal +1.715s	102.5%qual 101.3%

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.