BoP Lab / Classes / PX
PX vs GTX pace at every track
Lap times across years say as much about the weather as the class. % of PX is each class's best lap as a share of PX'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.
Closest to the field: GTX 107.5% of PX Derek Beitzel, Circuit of the Americas Super Tour Feb 2020 qualifying
| Event | PX | GTX | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Qual best | Race best | Trap | Qual best | Race best | Trap | vs PX | % of PX | |||
| 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.show
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| 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.show
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| 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.show
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| 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.show | ||||||||||
| 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.show
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| 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.show
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| 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.show
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| 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.show
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| 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.show
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| 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.show
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| 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.show
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| Buttonwillow Raceway Park Super Tour Feb 20222022-02-17 | 1:43.842Dave Tweedlie · only car | 1:44.025Dave Tweedlie · only car-9.156s (-8.09%) | 132.0Dave Tweedlie-1.5 mph (-1.1%) | 1:47.123Bob Blizzard · fastest of 2 | 1:48.781Bob Blizzard · fastest of 2 | 135.7Bob Blizzard | +4.756squal +3.281s | 104.6%qual 103.2% | ||
1 rule change (GTX: 1)1 engine · GTX-FIA GT3 all models lose intake restrictor requirements; McLaren name corrected.show
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| 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.show
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| 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 | 2:16.070Jim Booth · only car+7.555s (+5.88%) | 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%) | +12.374s qual | 109.1% qual | |||||
| No rule changes on record between these events | ||||||||||
| Virginia International Raceway Super Tour Apr 20212021-04-09 | 2:03.668Jacek Mucha · only car | 1:59.572Jacek Mucha · only car | 168.1Jacek Mucha | |||||||
| No rule changes on record between these events | ||||||||||
| Michelin Raceway Road Atlanta Super Tour Mar 20212021-03-19 | 1:29.991Jacek Mucha · only car | 1:28.432Jacek Mucha · only car | 171.7Jacek Mucha | 1:30.449Ben Johnston · only car | 1:30.784Ben Johnston · only car | 157.6Ben Johnston | +2.352squal +0.458s | 102.7%qual 100.5% | ||
| No rule changes on record between these events | ||||||||||
| Buttonwillow Raceway Park Super Tour Feb 20212021-02-19 | 1:53.181Robert Yallen · only car | 133.5Robert Yallen | ||||||||
1 rule change (GTX: 1)1 wording · GT1/GT2/GT3/GTL/GTX turbocharging and supercharging now permitted if listed on spec line.show
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| 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.show | ||||||||||
| 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.show
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| Road America June Sprints 20202020-06-12 | 2:08.515Judd Miller · fastest of 2 | 2:10.496Judd Miller · fastest of 2 | 166.2Conrad Park | 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 | +25.216squal +26.954s | 119.3%qual 121.0% | ||
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.show
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| Circuit of the Americas Super Tour Feb 20202020-02-07 | 2:11.851Judd Miller · only car | 2:08.836Judd Miller · only car | 162.9Judd Miller | 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 | +13.444squal +9.863s | 110.4%qual 107.5% | ||
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.show
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| Sebring International Raceway Super Tour Jan 20202020-01-10 | 2:11.545Jacek Mucha · only car | 2:11.901Jacek Mucha · only car | 155.9Jacek Mucha | 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%) | +4.121squal +3.856s | 103.1%qual 102.9% | ||
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.show
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| 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.show
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| 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.show
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By track
| Track | Events | Typical % of PX | Best | Latest |
|---|---|---|---|---|
| Road America | 7 | 100.0%2 of 7 with PX | 100.0%June Sprints 2020 | 100.0%June Sprints 2021 |
| Buttonwillow Raceway Park | 5 | 100.0%2 of 5 with PX | 100.0%Super Tour Feb 2021 | 100.0%Super Tour Feb 2022 |
| Michelin Raceway Road Atlanta | 5 | 100.0%1 of 5 with PX | 100.0%Super Tour Mar 2021 | 100.0%Super Tour Mar 2021 |
| Sebring International Raceway | 4 | 100.0%1 of 4 with PX | 100.0%Super Tour Jan 2020 | 100.0%Super Tour Jan 2020 |
| Virginia International Raceway | 4 | 100.0%1 of 4 with PX | 100.0%Super Tour Apr 2021 | 100.0%Super Tour Apr 2021 |
| Watkins Glen International | 3 | 0 of 3 with PX | ||
| Mid-Ohio Sports Car Course | 2 | 0 of 2 with PX | ||
| Barber Motorsports Park | 1 | 0 of 1 with PX | ||
| Circuit of the Americas | 1 | 100.0% | 100.0%Super Tour Feb 2020 | 100.0%Super Tour Feb 2020 |
| Pittsburgh International Race Complex | 1 | 0 of 1 with PX |
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 PX'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.