BoP Lab / Classes / SPU

SPU vs GTX pace at every track

SPUGTXsolid race · dashed qualifying · slower is lower

	Event	SPU			GTX
	Event	Qual best	Race best	Trap	Qual best	Race best	Trap	vs SPU
	Barber Motorsports Park Super Tour Aug 20262026-08-29				1:30.470Garry Crook · only car	1:31.890Garry Crook · only car	125.4Garry Crook
No rule changes on record between these events
	Road America June Sprints 20262026-06-05				2:07.194Anthony Smith · only car-12.897s (-9.21%)	1:59.377James French · fastest of 2-19.297s (-13.92%)	177.0James French+19.7 mph (+12.6%)
1 rule change (GTX: 1)1 cars added · Ferrari 296 GT3 added to GTX-MISC with homologation, restrictor, and minimum weight specifications effective 2026-04-01.showhide 2026-04-01 GTX Ferrari 296 GT3 Classification Request #39873cars addedaddedFerrari 296 GT3 added to GTX-MISC with homologation, restrictor, and minimum weight specifications effective 2026-04-01.
	Michelin Raceway Road Atlanta Super Tour Mar 20262026-03-06				1:27.748Garry Crook · only car+5.352s (+6.50%)	1:28.694Garry Crook · only car+8.785s (+10.99%)	151.5Garry Crook-1.8 mph (-1.2%)
1 rule change (GTX: 1)1 cars added · GT3U class removed from GCR; GT3U cars now compete in STU.showhide 2026-03-01 GTX Remove GT3U from GCR as it is now in STU #39862cars addedremovedcars addedGT3U class removed from GCR; GT3U cars now compete in STU.
	Buttonwillow Raceway Park Super Tour Feb 20262026-02-21				1:54.892Moze Cowper · only car+10.972s (+10.56%)	1:55.330Moze Cowper · only car+5.734s (+5.23%)	146.0Moze Cowper+29.6 mph (+25.4%)
1 rule change (GTX: 1)1 cars added · GTX adds RCR T70 Coupe, 2200 lbs minimum weight, no restrictor.showhide 2026-01-01 GTX Please Consider Adding a Spec Line to GTX Table 4 for the RCR T70 #39470cars addedaddedGTX adds RCR T70 Coupe, 2200 lbs minimum weight, no restrictor.
	Road America June Sprints 20252025-06-06
2 rule changes (GTX: 2)1 cars added · 1 engine · GTX Ligier LMP3 now allows any normally aspirated LS Chevrolet engine. · GTX adds Porsche GT2 RS Clubsport with factory specifications required at all race events.showhide 2025-06-01 GTX Ligier P3 LS Swap #38164engineaddedengineGTX Ligier LMP3 now allows any normally aspirated LS Chevrolet engine. 2025-05-01 GTX Request to Classify Porsche GT2 RS Clubsport #37972cars addedaddedGTX adds Porsche GT2 RS Clubsport with factory specifications required at all race events.
	Buttonwillow Raceway Park Super Tour Feb 20252025-02-22					1:49.596Rob Scholl · only car+3.511s (+3.31%)	116.4Rob Scholl-28.2 mph (-19.5%)
1 rule change (GTX: 1)1 wording · TA2 rear wing height rule clarified: OEM aerodynamic devices exempt from peak-of-roof height limit.showhide 2025-01-01 GTX Correct language regarding OEM Areo Devices #37137wordingwordingTA2 rear wing height rule clarified: OEM aerodynamic devices exempt from peak-of-roof height limit.
	Road America June Sprints 20242024-06-21				2:20.091Brian French · fastest of 3 · top 3 within 13.0s-0.378s (-0.27%)	2:18.674Brian French · fastest of 3 · top 3 within 14.2s-18.892s (-11.99%)	157.2Brian French-2.1 mph (-1.3%)
No rule changes on record between these events
	Watkins Glen International Super Tour May 20242024-05-31				1:55.821Rocky T Bolduc · fastest of 2-6.441s (-5.27%)	1:54.518Rocky T Bolduc · fastest of 2-6.036s (-5.01%)	166.4Rocky T Bolduc+18.2 mph (+12.3%)
1 rule change (GTX: 1)1 weight · GT2-ST Acura NSX minimum weight rises to 3000 lbs, restrictor increases to 45mm TIR.showhide 2024-05-01 GTX Request for Spec Line 1010 Reconsideration #35009weight +300 lbsslowerweightGT2-ST Acura NSX minimum weight rises to 3000 lbs, restrictor increases to 45mm TIR.
	Virginia International Raceway Super Tour Apr 20242024-04-04				1:55.869Woody Whichard · fastest of 2-21.281s (-15.52%)	1:55.430Woody Whichard · fastest of 2-6.419s (-5.27%)	162.5Woody Whichard+1.6 mph (+1.0%)
No rule changes on record between these events
	Michelin Raceway Road Atlanta Super Tour Mar 20242024-03-08				1:22.396Raiden Nicol · fastest of 3 · top 3 within 60.3s-8.436s (-9.29%)	1:19.909Raiden Nicol · fastest of 3 · top 3 within 14.2s-19.603s (-19.70%)	153.4Raiden Nicol+5.6 mph (+3.8%)
No rule changes on record between these events
	Buttonwillow Raceway Park Super Tour Feb 20242024-02-23				1:43.920Robert B. Yallen · only car-3.203s (-2.99%)	1:46.085Robert B. Yallen · only car-2.696s (-2.48%)	144.6Robert B. Yallen+8.9 mph (+6.5%)
7 rule changes (GTX: 7)3 cars added · 2 engine · 1 aero · 1 wording · GT1-GTX rear blade spoiler: angle 50–75°, max 59.0 wide by 5.0 high inches; total area limit removed. · GT1, GT2, GT3, GTL, GTX Direct Injection now permitted if original equipment. · GT2 Nissan and GT3 Mazda, Mitsubishi 4G93, Nissan QR25DE/DD, QE25DE/DD now permit Direct Injection per 9.1.2.F.7.5.E. · GTX KTM X-Bow added to class with restrictor and weight specification for 2024. · GTL spec lines moved contiguous with GT2 and GT3; GTA category and specs renumbered behind GTL; P2 engine tables reorganised with restrictor and weight specifications clarified. · GTX adds Ligier LMP3 with 3.7L NA engine, 22 mm restrictor, 2203 lbs minimum weight. · GTX adds Ligier JSP4 to MISC class; restrictor, weight and notes to be determined by SCCA.showhide 2024-02-01 GTX Rear Blade Spoiler Clarification #35261aeroaeroGT1-GTX rear blade spoiler: angle 50–75°, max 59.0 wide by 5.0 high inches; total area limit removed. 2024-02-01 GTX GT Direct Injection allowance and rules #35437engineaddedengineGT1, GT2, GT3, GTL, GTX Direct Injection now permitted if original equipment. 2024-02-01 GTX GT2/3 remove Direction Injection not allowed in Spec line notes #35439engineaddedengineGT2 Nissan and GT3 Mazda, Mitsubishi 4G93, Nissan QR25DE/DD, QE25DE/DD now permit Direct Injection per 9.1.2.F.7.5.E. 2024-01-01 GTX KTM X Bow GTX #34956cars addedaddedGTX KTM X-Bow added to class with restrictor and weight specification for 2024. 2023-12-01 GTX Errors in GTCS Headings and Use of the Terms Category and ClassChange existing GTL and GTA Rules #34453wordingwordingGTL spec lines moved contiguous with GT2 and GT3; GTA category and specs renumbered behind GTL; P2 engine tables reorganised with restrictor and weight specifications clarified. 2023-07-01 GTX Request Ligier LMP3 Classification #34043cars addedaddedGTX adds Ligier LMP3 with 3.7L NA engine, 22 mm restrictor, 2203 lbs minimum weight. 2023-07-01 GTX Ligier JSP4 Request #34173cars addedaddedGTX adds Ligier JSP4 to MISC class; restrictor, weight and notes to be determined by SCCA.
	Road America June Sprints 20232023-06-23				2:20.469Ray Ramirez · fastest of 2+2.326s (+1.68%)	2:37.566Erik Pylypchuk · fastest of 2+17.668s (+12.63%)	159.4Ray Ramirez+2.4 mph (+1.6%)
1 rule change (GTX: 1)1 cars added · Fields Cardinal V8 added to GT1 with Ford V8 engine, 4.9L, 2100 lbs, fuel injection.showhide 2023-05-01 GTX Please classify Fields Cardinal V8 #33784cars addedaddedFields Cardinal V8 added to GT1 with Ford V8 engine, 4.9L, 2100 lbs, fuel injection.
	Virginia International Raceway Super Tour Apr 20232023-04-07				2:17.150Jim Booth · fastest of 3 · top 3 within 10.0s+19.432s (+16.51%)	2:01.849Ray Ramirez · fastest of 3 · top 3 within 1.0s+7.544s (+6.60%)	160.9Ray Ramirez-18.6 mph (-10.4%)
No rule changes on record between these events
	Michelin Raceway Road Atlanta Super Tour Mar 20232023-03-10				1:30.832Steve Weber · only car+3.201s (+3.65%)	1:39.512Steve Weber · only car+14.097s (+16.50%)	147.8Steve Weber-25.3 mph (-14.6%)
No rule changes on record between these events
	Sebring International Raceway Super Tour Jan 20232023-01-13				2:02.230Jon Field · fastest of 3 · top 3 within 15.6s-2.976s (-2.38%)	2:02.253Jon Field · fastest of 3 · top 3 within 12.4s-3.439s (-2.74%)	147.8Jon Field-15.5 mph (-9.5%)
2 rule changes (GTX: 2)2 wording · GT2 TA2 and GTA throttle body part numbers updated to GM 12570790 or Edelbrock 33869/3870. · GT1, GT2, GT3, GTL, GTX tail lights may now be original style or custom panel graphic with functioning red LED brake lamps.showhide 2022-12-01 GTX GT2 (TA2)/GTA Part Number Update #33315wordingwordingGT2 TA2 and GTA throttle body part numbers updated to GM 12570790 or Edelbrock 33869/3870. 2022-09-01 GTX Tail lights on all GT category race cars. #32799wordingwordingGT1, GT2, GT3, GTL, GTX tail lights may now be original style or custom panel graphic with functioning red LED brake lamps.
	Road America June Sprints 20222022-06-17				2:18.143Grayson Farischon · fastest of 2-10.301s (-6.94%)	2:19.898Grayson Farischon · only car-7.941s (-5.37%)	156.9Grayson Farischon+29.6 mph (+23.2%)
No rule changes on record between these events
	Watkins Glen International Super Tour Jun 20222022-06-03				2:02.262Nio Fernandez · only car-10.115s (-7.64%)	2:00.554Nio Fernandez · only car-11.099s (-8.43%)	148.2Nio Fernandez+12.0 mph (+8.8%)
4 rule changes (GTX: 4)4 cars added · GTX adds Porsche 992 GT3 Cup Car; restrictor and specifications not stated in provided text. · GTX adds Wolf GB08 F1 Ford 52XS V8 NA at 1725 lbs minimum weight. · C7 Corvette Grand Sport added to GTX Misc with 3200 lbs minimum weight, displacement on demand valve train removable. · GTX eligible prototypes: IMSA GTP years changed to 1981-1993, plus five prototype categories newly allowed.showhide 2022-06-01 GTX Classify 992 GT3 Cup #32649cars addedaddedGTX adds Porsche 992 GT3 Cup Car; restrictor and specifications not stated in provided text. 2022-05-01 GTX Add Classification to the accepted Model Table #31981cars addedaddedGTX adds Wolf GB08 F1 Ford 52XS V8 NA at 1725 lbs minimum weight. 2022-05-01 GTX Request to classify C7 Corvette Grand Sport IN GTX Misc #32254cars addedaddedC7 Corvette Grand Sport added to GTX Misc with 3200 lbs minimum weight, displacement on demand valve train removable. 2022-05-01 GTX E&O list of eligible prototypes #32511cars addedaddedGTX eligible prototypes: IMSA GTP years changed to 1981-1993, plus five prototype categories newly allowed.
	Virginia International Raceway Super Tour Apr 20222022-04-08				1:57.718Jacek Mucha · fastest of 3 · top 3 within 5.5s	1:54.305Jacek Mucha · fastest of 3 · top 3 within 7.1s	179.6Jacek Mucha
No rule changes on record between these events
	Michelin Raceway Road Atlanta Super Tour Mar 20222022-03-12				1:27.631Jacek Mucha · only car-2.818s (-3.12%)	1:25.415Jacek Mucha · only car-5.369s (-5.91%)	173.1Jacek Mucha+15.4 mph (+9.8%)
1 rule change (GTX: 1)1 cars added · GTX McLaren 720s GT3 added to class with 30 mm restrictor and 3000 lbs minimum weight.showhide 2022-03-01 GTX McLaren 720s GT3 #31955cars addedaddedGTX McLaren 720s GT3 added to class with 30 mm restrictor and 3000 lbs minimum weight.
	Buttonwillow Raceway Park Super Tour Feb 20222022-02-17				1:47.123Bob Blizzard · fastest of 2	1:48.781Bob Blizzard · fastest of 2	135.7Bob Blizzard
1 rule change (GTX: 1)1 engine · GTX-FIA GT3 all models lose intake restrictor requirements; McLaren name corrected.showhide 2022-02-01 GTX Remove restrictions from GTX-FIA GT3 #32039enginefasterengineGTX-FIA GT3 all models lose intake restrictor requirements; McLaren name corrected.
	Sebring International Raceway Super Tour Jan 20222022-01-14				2:05.206Jacek Mucha · fastest of 2-10.195s (-7.53%)	2:05.692Jacek Mucha · fastest of 2-10.330s (-7.59%)	163.3Jacek Mucha+33.5 mph (+25.8%)
5 rule changes (GTX: 5)4 cars added · 1 wording · GT3 Volkswagen Fun Cup Beetle EVO3 classified, sealed SOHC 1984cc engine, 2060 lbs minimum weight. · GTX SRO-GT4: Porsche 718 Club Sport MR GT4 classified, unrestricted, 2900 lbs minimum weight. · GTA part numbers updated: 0-80541-1 to 0-80541-2 in two locations and 6010 to 6014X in TA2 Appendix. · Grullon GT 2.0L Acura K20 moved from GTX to GT2-ST class at 2350 lbs unrestricted. · GTX adds Grullon GT unrestricted with 2350 lbs minimum weight, factory spec required.showhide 2021-10-01 GTX Request car classification #31032cars addedaddedGT3 Volkswagen Fun Cup Beetle EVO3 classified, sealed SOHC 1984cc engine, 2060 lbs minimum weight. 2021-09-01 GTX Request to classify 2020 Porsche 718 GT4 Clubsport MR #30956cars addedaddedGTX SRO-GT4: Porsche 718 Club Sport MR GT4 classified, unrestricted, 2900 lbs minimum weight. 2021-08-01 GTX Request to Update GTA Obsolete Part Numbers #30615wordingwordingGTA part numbers updated: 0-80541-1 to 0-80541-2 in two locations and 6010 to 6014X in TA2 Appendix. 2021-08-01 GTX GTX class correction to GT2/ST #30973cars addedaddedGrullon GT 2.0L Acura K20 moved from GTX to GT2-ST class at 2350 lbs unrestricted. 2021-07-01 GTX Request classification of Grullon #30481cars addedaddedGTX adds Grullon GT unrestricted with 2350 lbs minimum weight, factory spec required.
	Watkins Glen International Super Tour Jun 20212021-06-18				2:12.377Andrew Wickline · only car	2:11.653Andrew Wickline · only car	136.2Andrew Wickline
No rule changes on record between these events
	Road America June Sprints 20212021-06-04				2:28.444William Hayes · fastest of 3 · top 3 within 0.7s-7.025s (-4.52%)	2:27.839Nio Fernandez · fastest of 3 · top 3 within 5.5s-7.873s (-5.06%)
No rule changes on record between these events
	Michelin Raceway Road Atlanta Super Tour Mar 20212021-03-19				1:30.449Ben Johnston · only car	1:30.784Ben Johnston · only car	157.6Ben Johnston
1 rule change (GTX: 1)1 wording · GT1/GT2/GT3/GTL/GTX turbocharging and supercharging now permitted if listed on spec line.showhide 2020-09-01 GTX GT Category Wording #29193wordingaddedGT1/GT2/GT3/GTL/GTX turbocharging and supercharging now permitted if listed on spec line.
	Pittsburgh International Race Complex Super Tour Aug 20202020-08-28				1:59.522Andrew Wickline · only car		120.9Andrew Wickline
2 rule changes (GTX: 2)2 cars added · GTX adds Chevrolet Camaro ZL1 with LT4 supercharged engine at 3400 lbs minimum weight. · GTX adds KTM X-Bow GT4, turbocharged 2.5L Audi TFSI I5, 2000 lbs minimum weight.showhide 2020-08-01 GTX Request Car classification #28935cars addedaddedGTX adds Chevrolet Camaro ZL1 with LT4 supercharged engine at 3400 lbs minimum weight. 2020-08-01 GTX X-Bow GT4 #29088cars addedaddedGTX adds KTM X-Bow GT4, turbocharged 2.5L Audi TFSI I5, 2000 lbs minimum weight.
	Mid-Ohio Sports Car Course Super Tour Jul 20202020-07-17				1:35.444Colin Cohen · only car+1.284s (+1.36%)	1:36.051Colin Cohen · only car+1.954s (+2.08%)	141.9Colin Cohen-0.5 mph (-0.3%)
3 rule changes (GTX: 3)3 wording · TA2 Gurney flap wording clarified: replace 'wicker bill' and 'wicker' with 'Gurney flap' throughout wing specifications. · STO rear wing rules clarify that wicker is called Gurney flap in two places; no performance change. · GT Gurney flap wording clarified: wickerbill and tab terminology replaced with Gurney flap throughout sections 9.1.2.F.7.b.showhide 2020-07-01 GTX TA2 Gurney flap wicker clarification #28874wordingwordingTA2 Gurney flap wording clarified: replace 'wicker bill' and 'wicker' with 'Gurney flap' throughout wing specifications. 2020-07-01 GTX STO Gurney flap wicker clarification #28883wordingwordingSTO rear wing rules clarify that wicker is called Gurney flap in two places; no performance change. 2020-07-01 GTX GT Gurney flap wicker clarification #28909wordingwordingGT Gurney flap wording clarified: wickerbill and tab terminology replaced with Gurney flap throughout sections 9.1.2.F.7.b.
	Road America June Sprints 20202020-06-12				2:35.469Tyler Gonzalez · fastest of 4 · top 4 within 3.2s	2:35.712Luke Lange · fastest of 3 · top 3 within 2.6s	127.4Luke Lange
2 rule changes (GTX: 2)2 cars added · GTX tube frame cars now permit stock car bodies; minimum weight 2780 pounds. · GTX Lotus Evora GTS added with 3.5L 2GR-FE engine, 2950 lbs minimum weight, OEM supercharger pulleys.showhide 2020-06-01 GTX Request to Re-classify SP Stock car to GTX #28333cars addedaddedGTX tube frame cars now permit stock car bodies; minimum weight 2780 pounds. 2020-05-01 GTX Request to Classify Lotus Evora GTS #27057cars addedaddedGTX Lotus Evora GTS added with 3.5L 2GR-FE engine, 2950 lbs minimum weight, OEM supercharger pulleys.
	Circuit of the Americas Super Tour Feb 20202020-02-07				2:21.714Derek Beitzel · fastest of 8 · top 5 within 10.3s	2:22.280Derek Beitzel · fastest of 8 · top 5 within 9.7s	156.4Sean Young
1 rule change (GTX: 1)1 other · GT1, GT2, GT3, GTL, GTX may use bonded-glass factory windshields without clips or straps if attached per original specifications.showhide 2020-02-01 GTX Windshield Clips #27323otheraddedGT1, GT2, GT3, GTL, GTX may use bonded-glass factory windshields without clips or straps if attached per original specifications.
	Sebring International Raceway Super Tour Jan 20202020-01-10				2:15.401Dean Copeland · only car+1.780s (+1.33%)	2:16.022Dean Copeland · only car+1.400s (+1.04%)	129.8Dean Copeland-11.5 mph (-8.2%)
1 rule change (GTX: 1)1 cars added · GTX Misc. adds Factory Five Type 65 Coupe R Ford 302/351 and 5.0/5.2L NA at 2600 lbs, plus Ferrari 458/488 Challenge, Ford FP350S, Chevrolet C6, Lamborghini Super Trofeo.showhide 2020-01-01 GTX Request Factory Five Daytona coupe classification #26308cars addedaddedGTX Misc. adds Factory Five Type 65 Coupe R Ford 302/351 and 5.0/5.2L NA at 2600 lbs, plus Ferrari 458/488 Challenge, Ford FP350S, Chevrolet C6, Lamborghini Super Trofeo.
	Mid-Ohio Sports Car Course Super Tour May 20192019-05-31				1:34.160Larry Funk · only car	1:34.097Larry Funk · only car	142.4Larry Funk
4 rule changes (GTX: 4)1 cars added · 1 engine · 2 wording · GTX tube frame cars now allowed fuel injection with maximum 90mm throttle body. · GTX adds Ligier JS2 R classification with restrictor and minimum weight. · GT1 and GT2/3/Lite remove ride height ground clearance rules; cars may now touch ground when tires deflate. · GTX strikes FIA GT4 references and replaces with SRO GT4.showhide 2019-05-01 GTX Request GTX Fuel injection for previous GT-1 tube frame cars #26141engineaddedengineGTX tube frame cars now allowed fuel injection with maximum 90mm throttle body. 2019-05-01 GTX Request to Classify Ligier JS2 R #26535cars addedaddedGTX adds Ligier JS2 R classification with restrictor and minimum weight. 2019-04-01 GTX Request Ride Height Clarification #26600wordingfasterGT1 and GT2/3/Lite remove ride height ground clearance rules; cars may now touch ground when tires deflate. 2019-03-01 GTX Replace FIA references with SRO #26427wordingwordingGTX strikes FIA GT4 references and replaces with SRO GT4.
	Sebring International Raceway Super Tour Jan 20192019-01-11				2:13.621Brian Kleeman · fastest of 3 · top 3 within 5.4s	2:14.622Ben Johnson · fastest of 3 · top 3 within 4.3s	141.3Ben Johnson
1 earlier rule change on record, in force before Super Tour Jan 2019 (from 2019)1 other · GTX FIA GT3: Audi R8 now 40 mm restrictor and 2900 lbs; BMW Z4 now 70 mm restrictor and 2800 lbs; Ferrari 488 now 35 mm restrictor, TIR, and 3025 lbs.showhide 2019-01-01 GTX GTX Homologation table update #26034otherunclearGTX FIA GT3: Audi R8 now 40 mm restrictor and 2900 lbs; BMW Z4 now 70 mm restrictor and 2800 lbs; Ferrari 488 now 35 mm restrictor, TIR, and 3025 lbs.

By track

Track	Events
Road America	7
Michelin Raceway Road Atlanta	5
Buttonwillow Raceway Park	4
Sebring International Raceway	4
Virginia International Raceway	3
Watkins Glen International	3
Mid-Ohio Sports Car Course	2
Barber Motorsports Park	1
Circuit of the Americas	1
Pittsburgh International Race Complex	1

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 the reference class'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.