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.
Closest to the field:STL 100.0% of STL Kevin Boehm, Daytona International Speedway Runoffs 2015 race · SM 96.8% of STL Brian Henderson, Indianapolis Motor Speedway Runoffs 2021 race · FV 95.5% of STL Alex Scaler, Indianapolis Motor Speedway Runoffs 2021 race · T1 84.5% of STL Mark Boden, Indianapolis Motor Speedway Runoffs 2021 race
STLSMFVT1solid race · dashed qualifying · slower is lower
STLSMFVT1solid 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
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%)
2:42.173Brett Kowalski · fastest of 34 · top 5 within 0.3s-0.938s (-0.58%)
2:42.725Francisco Barroso · fastest of 35 · top 5 within 0.2s-1.705s (-1.04%)
119.6Wyatt Couch+0.3 mph (+0.3%)
+12.068squal +11.636s
108.0%qual 107.7%
2:46.536Zachary Whitston · fastest of 37 · top 5 within 1.7s+2.435s (+1.48%)
2:45.272Brian Farnham · fastest of 34 · top 5 within 1.3s-1.464s (-0.88%)
117.4Rick Shields+0.2 mph (+0.1%)
+14.615squal +15.999s
109.7%qual 110.6%
18 rule changes (STL: 4, SM: 2, T1: 12)3 cars added · 2 engine · 2 weight · 1 aero · 1 induction · 1 removed · 1 tyres & wheels · 6 wording · 1 other · SM/SMX Mazda rear toe link part number revised from 0000-04-5361426 to 0000-04-5361. · STL removes Mazda MX-5 Cup entirely; renames Spec MX5 Challenge to Spec MX5; renames Global Cup to MX-5 Cup (16-18); removes Global Cup (2019). · T1 classes now require U-rated or better DOT tires; re-grooving DOT tires banned; shaving and truing only allowed. · STL, STU weight calculation procedure clarified: positive percentages added first, negative subtracted second, then fixed weights applied. · T1 trunk lid and wing mounting wording clarified; no performance change. · T1 LS1, LS6 removes OEM designation; 70mm restrictor requirement deleted. · T1 Spec Line Coyote Boss 302 production years corrected to 11–14, displacement 4957 cc unchanged. · SM/SMX part number 0000-10-6900 replaced with 0000-06-5016-KT in GCR 9.1.7.C.1.j.1.c. · STL adds Mazda BP 1.6, 1600cc, minimum weight 2160 lbs. · T1 restrictor requirement removed entirely; no replacement specified. · T1 GT4 Spec Line 4030- permits Wagner Tuning #200001124 intercooler as replacement for OEM heat exchanger. · T1 Chevrolet Corvette C6 LS1/LS6 spec line reinstated: 3200 lbs minimum, 70mm restrictor. · STL minimum weights increase across all engine sizes, 1300cc to 1850cc up to 195–250 lbs. · T1 Spec Line removes 70mm flat plate restrictor option. · unclear · T1 non-GT4 cars: multiple restrictor increases 61–80mm range, one weight raise to 3600 lbs, L76 engine clarified, throttle body permission removed. · T1 BMW M3 E92 (08-13) Spec Line 1090 removed entirely.showhide
SM Rear Toe Link #40271wordingwordingSM/SMX Mazda rear toe link part number revised from 0000-04-5361426 to 0000-04-5361.
STL Spec Line Clean Up #40344cars addedremovedcars addedSTL removes Mazda MX-5 Cup entirely; renames Spec MX5 Challenge to Spec MX5; renames Global Cup to MX-5 Cup (16-18); removes Global Cup (2019).
T1 Tire Equality #40342tyres & wheelstyres & wheelsT1 classes now require U-rated or better DOT tires; re-grooving DOT tires banned; shaving and truing only allowed.
STL Calculating Weight #40224wordingwordingSTL, STU weight calculation procedure clarified: positive percentages added first, negative subtracted second, then fixed weights applied.
T1 Trunk Lid Wording #40177wordingwordingT1 trunk lid and wing mounting wording clarified; no performance change.
T1 Clarification on Request #39716 T1 (Spec Line #1139) #39924wordingunclearT1 LS1, LS6 removes OEM designation; 70mm restrictor requirement deleted.
T1 Mistake in Line 1430 #39958wordingwordingT1 Spec Line Coyote Boss 302 production years corrected to 11–14, displacement 4957 cc unchanged.
SM Part Number Change Request #39914otherunclearSM/SMX part number 0000-10-6900 replaced with 0000-06-5016-KT in GCR 9.1.7.C.1.j.1.c.
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%)
2:43.111Bobby Gossett · fastest of 32 · top 5 within 0.3s+2.005s (+1.24%)
2:44.430Kyle Greenhill · fastest of 28 · top 5 within 0.3s+2.944s (+1.82%)
119.3Francisco Barroso-0.6 mph (-0.5%)
+12.303squal +11.046s
108.1%qual 107.3%
2:44.101Andrew Abbott · fastest of 34 · top 5 within 1.3s+1.458s (+0.90%)
2:46.736Zachary Whitston · fastest of 29 · top 5 within 0.6s+1.902s (+1.15%)
117.2Zachary Whitston+0.7 mph (+0.6%)
+14.609squal +12.036s
109.6%qual 107.9%
2:20.677James Candelaria · fastest of 5 · top 5 within 5.9s+4.099s (+3.00%)
2:21.612Drew Delmonico · fastest of 5 · top 5 within 11.8s+5.481s (+4.03%)
163.6Drew Delmonico+5.7 mph (+3.6%)
-10.515squal -11.388s
93.1%qual 92.5%
26 rule changes (STL: 3, SM: 4, T1: 19)6 cars added · 6 weight · 5 engine · 3 tyres & wheels · 1 aero · 4 wording · 1 other · Lotus Evora GT4 minimum weight drops to 2700 lbs; Elise Cup R to 2250 lbs; Elise SC and Exige SC to 2450–2550 lbs. · SMX drivers must submit data acquisition files on time or face suspension and $250 fine. · SMX penalty language clarified: level 1 and 3 infractions may carry $1,000 fines, level 2 and 4 may carry $500 fines. · SM tire marking rules clarified: one Hoosier SM 7.5 P205/50/ZR17 set per Super Tour weekend, impound after first dry session, damaged tires may be replaced with used tires only. · STL Mazda MX5 Challenge minimum weight now references GCR 9.1.7.1; mandatory component spec list removed, alternative tires only allowed. · Porsche 981 GT4 Clubsport added to T1 as Spec Line 4085, minimum weight 3100 lbs, 265/645 front and 305/680 rear tires. · T1 Honda S2000 Spec Line 1530 minimum weight drops 50 lbs to 2900. · T1 BMW E46 M3 permits BMW #GS7D36SG sequential transmission as aftermarket option in SL# 1060 and 1070. · T1 BMW M3 E92 minimum weight reduced to 3300 lbs. · T1 Mustang Darkhorse R tyres widen to 315 front and rear, weight set to 3600 lbs with driver, Runoffs eligibility requires 3 Super Tour events. · T1 Cadillac CT4-V Blackwing added: 3564cc, 3750 lbs minimum, OEM ECU with reprogramming allowed. · T1 Mustang Spec 1430 restrictor opens 60mm to 65mm; Spec 1460 weight up to 3500 lbs, restrictor 70mm; Corvette 1190 restrictor 67mm to 70mm; BMW 1090 restrictor tightens 40mm to 35mm, expires 12/31/25; BMW 1100 weight up to 3350 lbs. · T1 Mustang weight to 3600 lbs, restrictor to 60mm; Corvette weight to 3500 lbs, restrictor to 67mm; BMW deleted. · T1 E46 M3 Spec Line 1050 throttle body changed from Dinan D760-3400 to VAC Motorsports VAC-TB-S54 on 3.250L engine. · T1 Chevrolet Corvette C8 (2020-2023) minimum weight drops to 3500 lbs. · T1 Chevrolet Camaro Gen 5 required restrictor increases from 75mm to 80mm flat plate. · T1 Audi R8 GT4 Spec Line #4020 max tire size changes to 315 DOT, 305/645, or 30/65-18 (f), 33/68-18 (r) Non-DOT. · SMX OE instrument cluster must stay unmodified and connected; aftermarket dash allowed if wiring only re-routed; alternate gauges now permitted; foot pedal comfort mods allowed without relocation. · STL STU Mazda Miata alternate front hubs Mazda Motorsports Development Part #0000-04-5HUB-S1 approved. · T1 GT4 tire sizes standardized: most cars 315 DOT with 305/660 or 305/645 Non-DOT; Camaro 305/680, Mustang 315/680 Non-DOT. · BMW M4 GT4 (G82) added to T1 as spec line 4031, 3525 lbs minimum, red power stick; F82 model switched to red power stick. · T1 now permits 5.5 inch clutch as engine option. · T1 GT4 Spec Line 4020 restrictor opens to 45mm and minimum weight drops to 3400 lbs with driver. · T1 adds Mustang Darkhorse R homologated car, 305/315 tyres, 10.5/11 in wheels, minimum weight TBD. · T1 Corvette may roll or flatten wheel opening lips, remove composite fender lips and liners, and add fender vents for tire clearance. · T1 E46 M3 S54 now allows Dinan Throttle Body #D760-3400 on the 3.250L engine.showhide
STL Lotus Weight Reduction #38772weight -50 lbsfasterweightLotus Evora GT4 minimum weight drops to 2700 lbs; Elise Cup R to 2250 lbs; Elise SC and Exige SC to 2450–2550 lbs.
SM SMX Data Submission - Penalties #38248otheraddedSMX drivers must submit data acquisition files on time or face suspension and $250 fine.
SM Committee) SMX Penaly Clarification updated language #38337wordingwordingSMX penalty language clarified: level 1 and 3 infractions may carry $1,000 fines, level 2 and 4 may carry $500 fines.
SM Clarify Tire Marking Regs #38005wordingwordingSM tire marking rules clarified: one Hoosier SM 7.5 P205/50/ZR17 set per Super Tour weekend, impound after first dry session, damaged tires may be replaced with used tires only.
STL E&O: SMX Allowance in STL #37945wordingunclearSTL Mazda MX5 Challenge minimum weight now references GCR 9.1.7.1; mandatory component spec list removed, alternative tires only allowed.
T1 Acceptance of Porsche 981 GT4 Clubsport into T1 #36664cars addedaddedPorsche 981 GT4 Clubsport added to T1 as Spec Line 4085, minimum weight 3100 lbs, 265/645 front and 305/680 rear tires.
T1 Request to Restore T1 Honda S2000 to Proper Weights #37644weight -50 lbsfasterweightT1 Honda S2000 Spec Line 1530 minimum weight drops 50 lbs to 2900.
T1 DCT Transmission in E46 #37964cars addedaddedT1 BMW E46 M3 permits BMW #GS7D36SG sequential transmission as aftermarket option in SL# 1060 and 1070.
T1 Reduce E92 M3 Minimum Weight to 3050 #38092weightfasterweightT1 BMW M3 E92 minimum weight reduced to 3300 lbs.
T1 Finalize Spec Line for T1 Darkhorse #38106tyres & wheelsfastertyres & wheelsT1 Mustang Darkhorse R tyres widen to 315 front and rear, weight set to 3600 lbs with driver, Runoffs eligibility requires 3 Super Tour events.
T1 Correct and make new T1 BOP adjustments. #37737weight +75 lbsslowerweightT1 Mustang Spec 1430 restrictor opens 60mm to 65mm; Spec 1460 weight up to 3500 lbs, restrictor 70mm; Corvette 1190 restrictor 67mm to 70mm; BMW 1090 restrictor tightens 40mm to 35mm, expires 12/31/25; BMW 1100 weight up to 3350 lbs.
T1 T1 Parity Compared to GT4 #37170weight +125 lbsslowerweightT1 Mustang weight to 3600 lbs, restrictor to 60mm; Corvette weight to 3500 lbs, restrictor to 67mm; BMW deleted.
T1 Clarification of Request Approval #37273 #37399engineengineT1 E46 M3 Spec Line 1050 throttle body changed from Dinan D760-3400 to VAC Motorsports VAC-TB-S54 on 3.250L engine.
T1 C8 Corvette Facts #37400weight -100 lbsfasterweightT1 Chevrolet Corvette C8 (2020-2023) minimum weight drops to 3500 lbs.
T1 Camaro Gen 5 Competitive Disadvantage #37440enginefasterengineT1 Chevrolet Camaro Gen 5 required restrictor increases from 75mm to 80mm flat plate.
T1 Tire Changes in the Rules for GT4 #37497tyres & wheelstyres & wheelsT1 Audi R8 GT4 Spec Line #4020 max tire size changes to 315 DOT, 305/645, or 30/65-18 (f), 33/68-18 (r) Non-DOT.
SM E&O SMX Regs 9.1.7.1.D.5.u-.w #37070wordingwordingSMX OE instrument cluster must stay unmodified and connected; aftermarket dash allowed if wiring only re-routed; alternate gauges now permitted; foot pedal comfort mods allowed without relocation.
STL Request to Remove Miata Hubs from General category #37138cars addedaddedSTL STU Mazda Miata alternate front hubs Mazda Motorsports Development Part #0000-04-5HUB-S1 approved.
T1 Changes to T1 Tires for GT4 and Other Cars #35383tyres & wheelsunclearT1 GT4 tire sizes standardized: most cars 315 DOT with 305/660 or 305/645 Non-DOT; Camaro 305/680, Mustang 315/680 Non-DOT.
T1 G82 M4 GT4 inclusion in T1 #35864cars addedaddedBMW M4 GT4 (G82) added to T1 as spec line 4031, 3525 lbs minimum, red power stick; F82 model switched to red power stick.
T1 Alt. Clutch Allowance #36606engineaddedengineT1 now permits 5.5 inch clutch as engine option.
T1 BOP Changes Need Updates #36667engine -150 lbsfasterengineT1 GT4 Spec Line 4020 restrictor opens to 45mm and minimum weight drops to 3400 lbs with driver.
T1 Request Ford Performance Darkhorse R in T1 #37136cars addedaddedT1 adds Mustang Darkhorse R homologated car, 305/315 tyres, 10.5/11 in wheels, minimum weight TBD.
T1 Car Mods for T1 Corvette under line item 1150 #37173aeroaddedaeroT1 Corvette may roll or flatten wheel opening lips, remove composite fender lips and liners, and add fender vents for tire clearance.
T1 Increased Bore Throttle Bodies for E46 M3 S54 Engine #37273engineaddedengineT1 E46 M3 S54 now allows Dinan Throttle Body #D760-3400 on the 3.250L engine.
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%)
2:41.106Ethan Goulart · fastest of 49 · top 5 within 0.5s-1.103s (-0.68%)
2:41.486Brett Kowalski · fastest of 43 · top 5 within 0.3s-2.262s (-1.38%)
119.9Alex Bertagnoli-1.4 mph (-1.2%)
+11.241squal +11.043s
107.5%qual 107.4%
2:42.643Andrew Whitston · fastest of 27 · top 5 within 2.3s-1.351s (-0.82%)
2:44.834Andrew Abbott · fastest of 27 · top 5 within 0.9s-0.982s (-0.59%)
116.5Brian Farnham-0.7 mph (-0.6%)
+14.589squal +12.580s
109.7%qual 108.4%
2:16.578Andrew Aquilante · fastest of 8 · top 5 within 4.8s-1.068s (-0.78%)
2:16.131Andrew Aquilante · fastest of 7 · top 5 within 4.0s-2.570s (-1.85%)
157.9Andrew Aquilante-0.8 mph (-0.5%)
-14.114squal -13.485s
90.6%qual 91.0%
23 rule changes (STL: 4, SM: 4, FV: 2, T1: 13)9 cars added · 4 engine · 2 removed · 2 weight · 1 aero · 4 wording · 1 other · FV ferrous rotor must not be cross-drilled; pad cleaning grooves limit unchanged at three per side. · SMX Spec MX-5 camera requirement: non-functioning recorder now will instead of may warrant penalty or disqualification. · SM and SMX must run latest AIM Data Logger Spec MX-5 ECU Protocol, effective 2024-09-01. · SMX Mazda MX-5 OE versus OEM definitions clarified in GCR section 9.1.7.1; wording change only. · SM and SMX now allow an alternate shifter bushing at the bottom of the shift lever. · Mercedes AMG-C63 S 2023 added to T1 with 4000 cc, 3700 lb minimum weight, no restrictor. · T1 Honda S2000 classified: 1530 cc max, 2950 lbs minimum, 4.75" supercharger pulley, 6.75" crank pulley. · T1 adds Pontiac GTO 2006-2009 LS1 5700cc, 3400 lbs minimum, engine repositioning allowed. · STL and STU now permit electric power steering pumps, OEM electric-assisted steering, or column-mounted electric steering assist systems. · STL normally aspirated minimum weights reduced: 1900cc to 2540 lbs, 1950cc to 2583 lbs, 2000cc to 2625 lbs; short-wheelbase FWD adds 1.25%; Honda B16/B17/B18C1 throttle to 51mm, B18C Type R and Mazda MZR to 50mm. · STL Mazda 12A: 5th and 6th intake port actuators and valves may no longer be removed or disabled. · T1 Chevrolet Corvette C8 (2020–23) restrictor plate increases from 70mm to 72mm flat plate. · T1 category removes 23 car spec lines including NSX, Viper, Ferrari, Mazda, Nissan, Porsche, Subaru, Toyota; Porsche 997 spec line 1680 expiration removed. · STL 79-85 RX7 12A now allows auto-type 2 bbl carburetor with 42mm choke on dual-y manifold, not just stock Nikki. · T1 GT4 cars gain Runoffs eligibility; weights and power maps adjusted across six models; tire rules now allow IMSA or SRO GT4 slicks. · T1 removes 27 spec line numbers entirely, including engine, suspension, brake and aero specifications. · FV front wheel bearings wording clarified; specification unchanged. · T1 Chevrolet Corvette C5 LS2 added: 6000 cc, 3300 lbs minimum, 72mm restrictor, carbon aero option −50 lbs. · T1 adds Chevrolet Corvette C7 (14–19) including Z51, Grandsport as homologated car. · T1 Gen 5 Camaro minimum weight cut 75 lbs to 3475; restrictor opens from 70mm to 75mm flat plate. · T1 Aston Martin Vantage gains OEM Sportshift II transmission as permitted option. · Pontiac GTO 2006-2009 re-integrated to T1 with LS2 at 3400 lbs, 72mm restrictor, or LS3 at 3500 lbs, 61mm restrictor. · T1 Porsche 997-1 GT3 Cup added as spec line 4210, minimum weight 3050 lbs, 996 spec line 1670 removed.showhide
FV Disc Brakes #36822wordingwordingFV ferrous rotor must not be cross-drilled; pad cleaning grooves limit unchanged at three per side.
SM SMX Camera Rule Correction #36496wordingwordingSMX Spec MX-5 camera requirement: non-functioning recorder now will instead of may warrant penalty or disqualification.
SM Committee) AIM ECU Protocol #36556engineaddedengineSM and SMX must run latest AIM Data Logger Spec MX-5 ECU Protocol, effective 2024-09-01.
SM Committee) OE versus OEM Definitons #36608wordingwordingSMX Mazda MX-5 OE versus OEM definitions clarified in GCR section 9.1.7.1; wording change only.
SM Committee) Shifter Bushing #36611otheraddedSM and SMX now allow an alternate shifter bushing at the bottom of the shift lever.
T1 Please Expedite classing the C63 Mercedes #35987cars addedaddedMercedes AMG-C63 S 2023 added to T1 with 4000 cc, 3700 lb minimum weight, no restrictor.
T1 9.1.9.1 T1 new category item/ line 26 rule to expire Jan 1 2023 #35411cars addedaddedT1 adds Pontiac GTO 2006-2009 LS1 5700cc, 3400 lbs minimum, engine repositioning allowed.
STL ST Electric-Assisted Steering Systems #35066aeroaddedaeroSTL and STU now permit electric power steering pumps, OEM electric-assisted steering, or column-mounted electric steering assist systems.
STL BOP Adjustments #35112weightfasterweightSTL normally aspirated minimum weights reduced: 1900cc to 2540 lbs, 1950cc to 2583 lbs, 2000cc to 2625 lbs; short-wheelbase FWD adds 1.25%; Honda B16/B17/B18C1 throttle to 51mm, B18C Type R and Mazda MZR to 50mm.
STL Mazda 12A #35320engineremovedengineSTL Mazda 12A: 5th and 6th intake port actuators and valves may no longer be removed or disabled.
T1 C8 Corvette T1 Restrictor Plate Request #35213enginefasterengineT1 Chevrolet Corvette C8 (2020–23) restrictor plate increases from 70mm to 72mm flat plate.
T1 The Cars Have Expired #35379removedremovedT1 category removes 23 car spec lines including NSX, Viper, Ferrari, Mazda, Nissan, Porsche, Subaru, Toyota; Porsche 997 spec line 1680 expiration removed.
STL Alternate Carburetor Request for 79-85 RX7 12a #35181engineaddedengineSTL 79-85 RX7 12A now allows auto-type 2 bbl carburetor with 42mm choke on dual-y manifold, not just stock Nikki.
T1 GT4 batch adjustment in T1 #35162cars added -85 lbsaddedT1 GT4 cars gain Runoffs eligibility; weights and power maps adjusted across six models; tire rules now allow IMSA or SRO GT4 slicks.
T1 Remove T1 spec lines #35192removedremovedT1 removes 27 spec line numbers entirely, including engine, suspension, brake and aero specifications.
T1 New T1 add spec line for C5 corvette LS2 engines (Copy from C6) #33764cars addedaddedT1 Chevrolet Corvette C5 LS2 added: 6000 cc, 3300 lbs minimum, 72mm restrictor, carbon aero option −50 lbs.
T1 C7 Corvette Rule Change Request #34897cars addedaddedT1 adds Chevrolet Corvette C7 (14–19) including Z51, Grandsport as homologated car.
T1 Camaro Gen 5 Weight Reduction Due to Competitive Disadvantage #35092weight -75 lbsfasterweightT1 Gen 5 Camaro minimum weight cut 75 lbs to 3475; restrictor opens from 70mm to 75mm flat plate.
T1 Addendum to Letter #35022: Drivetrain Rule #35105cars addedaddedT1 Aston Martin Vantage gains OEM Sportshift II transmission as permitted option.
T1 2004 - 2006 Pontiac GTO Re-Integration Back Into T1 #34403cars addedaddedPontiac GTO 2006-2009 re-integrated to T1 with LS2 at 3400 lbs, 72mm restrictor, or LS3 at 3500 lbs, 61mm restrictor.
T1 Request to Classify Porsche 997-1 GT3 Cup #34561cars addedaddedT1 Porsche 997-1 GT3 Cup added as spec line 4210, minimum weight 3050 lbs, 996 spec line 1670 removed.
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%)
2:14.986Danny Steyn · fastest of 52 · top 5 within 0.1s+0.322s (+0.24%)
2:16.229Julian DaCosta · fastest of 46 · top 5 within 0.3s-2.878s (-2.07%)
120.3Jim Drago+1.1 mph (+0.9%)
+9.547squal +9.207s
107.5%qual 107.3%
2:15.639Andrew Whitston · fastest of 27 · top 5 within 1.4s+0.523s (+0.39%)
2:16.611Andrew Abbott · fastest of 23 · top 5 within 1.6s-1.482s (-1.07%)
115.6Brian Farnham-0.2 mph (-0.2%)
+9.929squal +9.860s
107.8%qual 107.8%
1:54.520Andrew Aquilante · fastest of 12 · top 5 within 3.7s-0.370s (-0.32%)
1:55.488Andrew Aquilante · fastest of 12 · top 5 within 2.7s-20.579s (-15.12%)
159.2James Candelaria+1.6 mph (+1.0%)
-11.194squal -11.259s
91.2%qual 91.0%
22 rule changes (STL: 2, SM: 1, T1: 19)6 cars added · 4 engine · 3 weight · 2 tyres & wheels · 1 aero · 1 induction · 1 removed · 4 wording · Chevrolet Camaro GT4-R added to T1 GT4 Spec Line 4035, 315 tires, 3375 lbs minimum, ineligible for Runoffs. · T1 Dodge Viper ACR / SRT RT-10 and ACR/ACR-X spec lines 1350 and 1370 remove 12/23 expiration dates. · T1 GT4 McLaren 570S, Mercedes AMG GT4, and Porsche 718 Cayman GT4 CS MR now eligible for Runoffs competition. · T1 GT4 BMW M4 spec line number changed from 4050 to 4030. · T1 Chevrolet Corvette C5 rear spoiler to 5 inches above bumper allowed, plus 50 lbs; carbon aero parts permitted with 50 lb decrease. · T1 Dodge Viper ACR/ACR-X restrictor increases from 50mm to 60mm flat plate. · T1 Dodge Viper ACR/ACR-X Spec Line 1370 restrictor increases to 55mm; Spec Line 1390 decreases to 55mm flat plates. · T1 Ford Mustang S197 (05-14) must use OEM 8.8 differential housing. · T1 Chevrolet Camaro Gen 5 LS7 gains two spec lines with 70mm and 53mm restrictors, both 3450 lbs minimum. · T1 Chevrolet Camaro Gen 5, Corvette C5 and C6: resleeve restricted to stock parameters for engine repair or replacement, not LS3 bore/stroke. · STL ITA and ITS RX7, and ITS/ITA/ITB/ITC 1985+ models clarified to require tires per 9.1.4.2. · T1 Ford Mustang S197 (05-14) reinstated with 5.0L Voodoo engine, 3550 lbs minimum, 75mm restrictor. · T1-GT4 minimum weights set: Aston Martin Vantage AMR 3575 lbs, Audi R8 3550, BMW M4 3500, Ford Mustang 3550, McLaren 570S 3450, Mercedes AMG 3450, Porsche 718 Cayman CS MR 3200, Porsche 718 RS 3450, Toyota Supra 3350. · T1-GT4 McLaren 570S front tyre widens from 285 to 315; Mercedes AMG GT4 front tyre widens from 275 to 315. · T1 Chevrolet Camaro Gen 5 LS3-6160 adds new Spec Line 1135 with 70mm flat plate restrictor, 3550 lbs minimum weight. · T1 aftermarket sequential gearbox cars must have 1:1 or greater top gear ratio, OEM location, max 10 inch bellhousing; non-sequential cars gain 100 lbs weight break. · T1 GT4 all nine cars lose 125 lbs minimum weight with driver across the range. · T1 pre-2023 rules and spec lines removed entirely, effective 2023-03-01. · GT4 McLaren 570S maximum tyre size set to 285 front, 315 rear. · SM Mazda MX-5 Miata 01-05 minimum weight rises to 2450 lbs, or 2465 with alternate bore. · Spec MX5 in STL allows ACT clutch 0000-02-5004-G6, wheels 17x8, Toyo RR and RA1 235-40-17 tyres, or alternatives on 17x7 per rules. · T1 adds eight GT4 cars: Aston Martin, Audi, BMW, Ford, McLaren, Mercedes, two Porsches, Toyota, minimum weights 3200–3575 lbs, restricted by SRO 2022 rules.showhide
T1 Why no Camaro? #34421cars addedaddedChevrolet Camaro GT4-R added to T1 GT4 Spec Line 4035, 315 tires, 3375 lbs minimum, ineligible for Runoffs.
T1 Request to Remove Expiration from T1 spec lines #1350 & #1370 #34470wordingwordingT1 Dodge Viper ACR / SRT RT-10 and ACR/ACR-X spec lines 1350 and 1370 remove 12/23 expiration dates.
T1 Remove #34475cars addedaddedT1 GT4 McLaren 570S, Mercedes AMG GT4, and Porsche 718 Cayman GT4 CS MR now eligible for Runoffs competition.
T1 Error in T1 GT4 numbering scheme- #34578wordingwordingT1 GT4 BMW M4 spec line number changed from 4050 to 4030.
T1 C5 Approved Aero That Was Mistakenly Deleted #34374aerosloweraeroT1 Chevrolet Corvette C5 rear spoiler to 5 inches above bumper allowed, plus 50 lbs; carbon aero parts permitted with 50 lb decrease.
T1 Viper Cleanup #34107inductionfasterinductionT1 Dodge Viper ACR/ACR-X restrictor increases from 50mm to 60mm flat plate.
T1 Viper 8300 OEM FPR Size #34268engineunclearT1 Dodge Viper ACR/ACR-X Spec Line 1370 restrictor increases to 55mm; Spec Line 1390 decreases to 55mm flat plates.
T1 Ford Mustang S197 (05-14) Clarification #34450wordingwordingT1 Ford Mustang S197 (05-14) must use OEM 8.8 differential housing.
T1 Gen 5 Camaro Engine #33875cars addedaddedT1 Chevrolet Camaro Gen 5 LS7 gains two spec lines with 70mm and 53mm restrictors, both 3450 lbs minimum.
T1 Inquiry to letter #33682 #34071engineslowerengineT1 Chevrolet Camaro Gen 5, Corvette C5 and C6: resleeve restricted to stock parameters for engine repair or replacement, not LS3 bore/stroke.
STL Clarify STL table B - IT spec notes on Tires #34187wordingwordingSTL ITA and ITS RX7, and ITS/ITA/ITB/ITC 1985+ models clarified to require tires per 9.1.4.2.
T1 Request to reinstate T1 S197 Mustang #34048cars addedaddedT1 Ford Mustang S197 (05-14) reinstated with 5.0L Voodoo engine, 3550 lbs minimum, 75mm restrictor.
T1 T1 GT4 adjustments #33786weightunclearT1-GT4 minimum weights set: Aston Martin Vantage AMR 3575 lbs, Audi R8 3550, BMW M4 3500, Ford Mustang 3550, McLaren 570S 3450, Mercedes AMG 3450, Porsche 718 Cayman CS MR 3200, Porsche 718 RS 3450, Toyota Supra 3350.
T1 Touring 1 Tire Sizes #34191tyres & wheelsfastertyres & wheelsT1-GT4 McLaren 570S front tyre widens from 285 to 315; Mercedes AMG GT4 front tyre widens from 275 to 315.
T1 Clarification for Camaro Gen5 2010-2015 #33739engineslowerengineT1 Chevrolet Camaro Gen 5 LS3-6160 adds new Spec Line 1135 with 70mm flat plate restrictor, 3550 lbs minimum weight.
T1 Sequential Gearbox Limitations in T1 #33691engineaddedengineT1 aftermarket sequential gearbox cars must have 1:1 or greater top gear ratio, OEM location, max 10 inch bellhousing; non-sequential cars gain 100 lbs weight break.
T1 T1 GT4 adjustments #33786weightfasterweightT1 GT4 all nine cars lose 125 lbs minimum weight with driver across the range.
T1 Sunset of pre 2023 Touring 1 Rules. #33916removedremovedT1 pre-2023 rules and spec lines removed entirely, effective 2023-03-01.
T1 Corrections to T1 Spec Lines #33678tyres & wheelstyres & wheelsGT4 McLaren 570S maximum tyre size set to 285 front, 315 rear.
SM BOP for NB1 and NB2 #32309weightslowerweightSM Mazda MX-5 Miata 01-05 minimum weight rises to 2450 lbs, or 2465 with alternate bore.
STL Spec MX5 in STL #33473cars addedaddedSpec MX5 in STL allows ACT clutch 0000-02-5004-G6, wheels 17x8, Toyo RR and RA1 235-40-17 tyres, or alternatives on 17x7 per rules.
T1 GT4 section to Current T1 Rules. #33632cars addedaddedT1 adds eight GT4 cars: Aston Martin, Audi, BMW, Ford, McLaren, Mercedes, two Porsches, Toyota, minimum weights 3200–3575 lbs, restricted by SRO 2022 rules.
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%)
2:14.664Danny Steyn · fastest of 60 · top 5 within 0.2s+0.112s (+0.08%)
2:19.107Travis Wiley · fastest of 58 · top 5 within 0.9s+2.648s (+1.94%)
119.2Jonathan Neudorf-0.6 mph (-0.5%)
+11.275squal +9.190s
108.8%qual 107.3%
2:15.116Brian Farnham · fastest of 29 · top 5 within 1.1s-0.596s (-0.44%)
2:18.093Andrew Whitston · fastest of 28 · top 5 within 1.2s-0.196s (-0.14%)
115.8Jonathan Weisheit+1.1 mph (+0.9%)
+10.261squal +9.642s
108.0%qual 107.7%
1:54.890Andrew Aquilante · fastest of 10 · top 5 within 3.2s+0.119s (+0.10%)
2:16.067Andrew Aquilante · fastest of 8 · top 5 within 15.9s+1.654s (+1.23%)
157.5Mark Boden+1.3 mph (+0.8%)
+8.235squal -10.584s
106.4%qual 91.6%
21 rule changes (STL: 5, SM: 1, FV: 4, T1: 11)5 engine · 5 weight · 3 cars added · 1 suspension & brakes · 1 tyres & wheels · 6 wording · T1 Camaro, CTS, Firebird, GTO minimum weight reduced to 3475 lbs from 3500 lbs. · T1-LP Ford Mustang FP350S restrictor increases from 70mm to 75mm. · Mercedes-Benz AMG GT4 (2017-2021) added to T1 with 3400 lb minimum weight, SRO Power Level 2 engine control. · SM Majors must run authorized Penske shock and mount; Regional competitors not required until further evaluation. · T1 Dodge Viper ACR displacement rises to 8400 cc OEM, minimum weight drops to 3550 lbs. · T1 Limited T1 specification reference removed; all T1 cars now have unified allowances. · T1 Mazda RX-7 added: 2700 lbs minimum weight, 44mm restrictor, 13B rotary with single Garrett Turbo #3076. · FV connecting rod options expanded to include BrianCrower part BC6417 and Newland Group part 4M113077. · FV connecting rods minimum weight 425.0 grams, center-to-center length 130 +0.10/-0.25 mm; Crower, BrianCrower, Newland Group parts allowed if meeting specs. · STU single throttle body weight reduction removed; minimum weights revised down to 2990 lbs at 3000cc from 3300 lbs. · STL and STU Improved Touring vehicles must now conform to section 9.1.4 Tires & Wheels. · T1 Cadillac CTS/CTS-V, Chevrolet Camaro, Pontiac Firebird, Pontiac GTO LS3 minimum weight reduced to 3475 lbs. · T1 Camaro, CTS, Firebird, GTO with 7011 max displacement loses 50 lbs, to 3500. · T1 brake rotors no longer limited to 33mm thickness maximum. · FV Crower connecting rods SP93280B and BC6417 allowed as direct replacement, must meet OEM minimum weight. · STL/STU intake manifold and cylinder head porting clarified as free; intake and exhaust porting wording removed. · STL Mazda Renesis flat plate restrictor increases from 55mm to 60mm. · STL 79-85 RX7 12A allows emissions removal and jet correction on stock Nikki carb. · FV allows Crower SP93280B and Brian Crower Racing Rods connecting rods as direct replacements, matching OEM minimum weight. · T1 Mazda MX-5 Miata MazdaSpeed minimum weight rises to 2550 lbs, restrictor grows to 42mm. · T1 Chevrolet Corvette Cadillac XLR classified as model year 2019 and earlier.showhide
T1 Correct Camaro Spec Line From Letter #30791 response to 3475lbs #32824weight -25 lbsfasterweightT1 Camaro, CTS, Firebird, GTO minimum weight reduced to 3475 lbs from 3500 lbs.
T1 Fix FP350S limited prep and Shelby 350 full prep issues #31680enginefasterengineT1-LP Ford Mustang FP350S restrictor increases from 70mm to 75mm.
T1 Request to Classify AMG GT4 #32610cars addedaddedMercedes-Benz AMG GT4 (2017-2021) added to T1 with 3400 lb minimum weight, SRO Power Level 2 engine control.
SM Update GCR Section 9.1.7.3.A.1. #32217wordingwordingSM Majors must run authorized Penske shock and mount; Regional competitors not required until further evaluation.
T1 Viper/Z06 Parity #31942engine -50 lbsfasterengineT1 Dodge Viper ACR displacement rises to 8400 cc OEM, minimum weight drops to 3550 lbs.
T1 Discrepancy in T1 allowances #32293wordingwordingT1 Limited T1 specification reference removed; all T1 cars now have unified allowances.
FV Connecting Rod Update Request for 9.1.1.C Formula Vee (FV) 5.C.6 #32160engineaddedengineFV connecting rod options expanded to include BrianCrower part BC6417 and Newland Group part 4M113077.
FV E&O clarification of connecting rod center-to-center length #32183wordingwordingFV connecting rods minimum weight 425.0 grams, center-to-center length 130 +0.10/-0.25 mm; Crower, BrianCrower, Newland Group parts allowed if meeting specs.
STL Single TB Weight Modifiers #31449weightfasterweightSTU single throttle body weight reduction removed; minimum weights revised down to 2990 lbs at 3000cc from 3300 lbs.
STL Improved Touring Tires #32063tyres & wheelstyres & wheelsSTL and STU Improved Touring vehicles must now conform to section 9.1.4 Tires & Wheels.
FV Update direct replacement connecting rod information #31843wordingwordingFV Crower connecting rods SP93280B and BC6417 allowed as direct replacement, must meet OEM minimum weight.
STL Throttling Device Clarification #31323wordingwordingSTL/STU intake manifold and cylinder head porting clarified as free; intake and exhaust porting wording removed.
STL Mazda Renesis Restriction #31467enginefasterengineSTL Mazda Renesis flat plate restrictor increases from 55mm to 60mm.
STL Clarification of 79-85 RX7 Spec line #31621wordingwordingSTL 79-85 RX7 12A allows emissions removal and jet correction on stock Nikki carb.
FV Formula V Connecting Rod Replacement #31448engineaddedengineFV allows Crower SP93280B and Brian Crower Racing Rods connecting rods as direct replacements, matching OEM minimum weight.
T1 Turbo Miata Help #31315weight +200 lbsslowerweightT1 Mazda MX-5 Miata MazdaSpeed minimum weight rises to 2550 lbs, restrictor grows to 42mm.
T1 Fix the T1 Corvette heading #31528cars addedaddedT1 Chevrolet Corvette Cadillac XLR classified as model year 2019 and earlier.
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
1:57.695Brian Henderson · fastest of 90 · top 5 within 0.5s-0.611s (-0.52%)
1:58.837Brian Henderson · fastest of 88 · top 5 within 0.3s-0.263s (-0.22%)
119.8Kyle Greenhill
-3.874squal +6.030s
96.8%qual 105.4%
1:57.479Andrew Whitston · fastest of 48 · top 5 within 0.8s+1.720s (+1.49%)
1:57.234Alex Scaler · fastest of 47 · top 5 within 1.0s+1.311s (+1.13%)
124.0Mark Edwards
-5.477squal +5.814s
95.5%qual 105.2%
1:42.292Andrew Aquilante · fastest of 22 · top 5 within 1.3s+0.499s (+0.49%)
1:43.752Mark Boden · fastest of 22 · top 5 within 1.0s+0.881s (+0.86%)
159.2Mark Boden
-18.959squal -9.373s
84.5%qual 91.6%
34 rule changes (STL: 15, SM: 1, T1: 18)9 cars added · 7 engine · 7 weight · 2 aero · 2 induction · 1 suspension & brakes · 4 wording · 2 other · STL Mazda Spec MX-5 removes redundant specification line referencing 2014 regulations. · T1 BMW E46, E36, Z3 minimum weight raised to 2700 lbs; 3.4L engine car to 2750 lbs. · T1 Dodge Viper SRT-10 restrictor increases from 45mm to 57mm. · T1 Corvette and Cadillac XLR: Casting #799 heads now permitted on LS6 engines, no other head modifications allowed. · STL Volkswagen 2.0L TFSI 1984 cc engine permitted without turbocharger, meeting all other STL specs. · T1 Mustang GT5.0L 18+ Performance Pack, Bullet, Mach 1 allowed with 100 lb penalty; Shelby/GT350/GT500 restrictor opens 65 mm to 70 mm. · T1 Dodge Viper SRT-10 Incl. Coupe 08-10 restrictor increases from 45mm to 57mm. · T1 Corvette C7 Grand Sport now included; intake restrictor increases from 70 mm to 73 mm. · T1 Corvette Z06 06-13 now allows aluminum chassis replacement with equivalent OE steel chassis. · STL Pontiac Solstice/Saturn Sky allowed 4 inch ride height. · STL Mazda B5 DOHC added to class; must meet all STL regulations. · STL Honda B16A (JDM) restrictor reduced from 54mm to 53mm. · T1 Chevrolet Camaro with 6162 displacement minimum weight reduced to 3500 lbs. · T1-LP Chevrolet Corvette C5 Z06, C6 Grand Sport, and Z06 dry sump kit notes clarified to remove duplicates. · SM adds procedure for CRB-approved obsolete parts and BOP testing in sanctioned events with point forfeiture. · ST oil coolers and filters now explicitly listed as addable or substitutable parts in vents and breathers section. · STL GM Ecotec LNF now permits any Ecotec engine family with 55mm flat plate restrictor. · ST 90-05 Mazda Miata allowed alternate front wheel hub Mazda Motorsports Development Part #0000-04-5HUB-S1. · T1 LP aero adjustments: removed 50 lb weight allowance for stock OEM manifold/headers, reorganised aero and engine durability allowances into numbered list. · ST cars may now relocate ABS actuation hardware and wiring anywhere in the engine compartment. · STL rear wing trailing edge may be mounted no further rearward than the center of the rearmost part approved bodywork. · STL alternate transmissions now allow OEM gear sets and input shaft modifications for fitment. · T1 Ford Mustang Challenge maximum displacement changes to 4600 cc for 3-valve engines, 5000 cc for others. · T1 BMW E46 allows carbon or fiberglass OEM-style dashboards with 25 pound weight penalty instead of requiring stock dash pad. · T1 Ford Mustang/Thunderbird specification removed Thunderbird model; now Shelby/Shelby GT350/GT500 only through 2018. · T1 Dodge Viper ACR 8400cc OEM added with 3600 lb minimum weight, 55mm flat-plate restrictor. · BMW M2CS Club Sport added to T1 Spec Lines classification. · Porsche 997.1 GT3 Cup (2006–2011) classified in T1 at 3600cc displacement, 3150 lbs minimum weight, no restrictor. · STL RWD strut-front cars lose 2.5% weight penalty, others lose 3% penalty for FWD parity. · STL Honda F20C drops 2% weight penalty, minimum weight reduced. · STL Honda B16/B17/B18C1 restrictor reduced to 53mm, B18C variants and Mazda MZR to 52mm. · T1 Limited Prep Chevrolet Corvette Z06 years extend to 2013, from 2012. · ST aero devices and reference areas must include end plates, exclude fasteners under 1/2" protrusion. · T1 Corvette C8 Z51 gets wider wheels and tyres, loses 100 lbs to 3550.showhide
STL Request to clean up Spec MX-5 Redundancy #31069wordingwordingSTL Mazda Spec MX-5 removes redundant specification line referencing 2014 regulations.
T1 T1 E46 BOP E&O for Letter # 29970 #30934weight +100 lbsslowerweightT1 BMW E46, E36, Z3 minimum weight raised to 2700 lbs; 3.4L engine car to 2750 lbs.
T1 Request BoP for the Viper in 1 LP #29968enginefasterengineT1 Dodge Viper SRT-10 restrictor increases from 45mm to 57mm.
T1 LS6 Alternative Head Question #30074cars addedaddedT1 Corvette and Cadillac XLR: Casting #799 heads now permitted on LS6 engines, no other head modifications allowed.
STL VW Engine Request #30625engineaddedengineSTL Volkswagen 2.0L TFSI 1984 cc engine permitted without turbocharger, meeting all other STL specs.
T1 T1-LP - Add Performance Pack, Bullet, Mach 1 to 18+ Mustang #29849enginefasterengineT1 Mustang GT5.0L 18+ Performance Pack, Bullet, Mach 1 allowed with 100 lb penalty; Shelby/GT350/GT500 restrictor opens 65 mm to 70 mm.
T1 Request BoP for the Viper in 1 LP #29968enginefasterengineT1 Dodge Viper SRT-10 Incl. Coupe 08-10 restrictor increases from 45mm to 57mm.
T1 Request to classify C7 and 13Viper in T1 LP #29969inductionfasterinductionT1 Corvette C7 Grand Sport now included; intake restrictor increases from 70 mm to 73 mm.
STL Request Mazda B5 DOHC #30420cars addedaddedSTL Mazda B5 DOHC added to class; must meet all STL regulations.
STL Honda B16A (JDM) Restrictor change #30531engineslowerengineSTL Honda B16A (JDM) restrictor reduced from 54mm to 53mm.
T1 Request For Reduction in Weight/Penalties for Camaro #30443weightfasterweightT1 Chevrolet Camaro with 6162 displacement minimum weight reduced to 3500 lbs.
T1 Fix dry sump Contradictions in T1-LP vs T2 #30596wordingwordingT1-LP Chevrolet Corvette C5 Z06, C6 Grand Sport, and Z06 dry sump kit notes clarified to remove duplicates.
SM Updates - Obsolete Parts & BOP Parts #30438wordingaddedSM adds procedure for CRB-approved obsolete parts and BOP testing in sanctioned events with point forfeiture.
STL ST Oil Coolers E&O Correction to 9.1.4.2.H #30388wordingwordingST oil coolers and filters now explicitly listed as addable or substitutable parts in vents and breathers section.
STL GM Ecotec engines in STL #30247engineaddedengineSTL GM Ecotec LNF now permits any Ecotec engine family with 55mm flat plate restrictor.
STL Super Touring Alternate Miata Hubs #30345cars addedaddedST 90-05 Mazda Miata allowed alternate front wheel hub Mazda Motorsports Development Part #0000-04-5HUB-S1.
T1 T1 LP Aero adjustments #30196weightslowerweightT1 LP aero adjustments: removed 50 lb weight allowance for stock OEM manifold/headers, reorganised aero and engine durability allowances into numbered list.
STL Brake Component Relocation #29990suspension & brakessuspension & brakesST cars may now relocate ABS actuation hardware and wiring anywhere in the engine compartment.
STL Super Touring Wing Clarification #30111aeroaeroSTL rear wing trailing edge may be mounted no further rearward than the center of the rearmost part approved bodywork.
STL Transmission Options #30118otheraddedSTL alternate transmissions now allow OEM gear sets and input shaft modifications for fitment.
T1 Request to Clarify Miller Mustang Classification #28728engineengineT1 Ford Mustang Challenge maximum displacement changes to 4600 cc for 3-valve engines, 5000 cc for others.
T1 BMW E46 Carbon Dash #29806weightslowerweightT1 BMW E46 allows carbon or fiberglass OEM-style dashboards with 25 pound weight penalty instead of requiring stock dash pad.
T1 Request to Update T1 Mustang Spec Line #30001cars addedremovedcars addedT1 Ford Mustang/Thunderbird specification removed Thunderbird model; now Shelby/Shelby GT350/GT500 only through 2018.
T1 Class BMW M2CS Club Sport #30195cars addedaddedBMW M2CS Club Sport added to T1 Spec Lines classification.
T1 997.1 GT3 Cup #30229cars addedaddedPorsche 997.1 GT3 Cup (2006–2011) classified in T1 at 3600cc displacement, 3150 lbs minimum weight, no restrictor.
STL Request for FWD and RWD Parity #29728weightfasterweightSTL RWD strut-front cars lose 2.5% weight penalty, others lose 3% penalty for FWD parity.
STL Request for FWD and RWD Parity #30023inductionslowerinductionSTL Honda B16/B17/B18C1 restrictor reduced to 53mm, B18C variants and Mazda MZR to 52mm.
T1 Correct T1 Limited Prep Years #29708cars addedaddedT1 Limited Prep Chevrolet Corvette Z06 years extend to 2013, from 2012.
STL Request clarification on wing measurement #29640aeroaeroST aero devices and reference areas must include end plates, exclude fasteners under 1/2" protrusion.
T1 Changes to Corvette C8 #29898weight -100 lbsfasterweightT1 Corvette C8 Z51 gets wider wheels and tyres, loses 100 lbs to 3550.
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
2:42.209Kyle Greenhill · fastest of 77 · top 5 within 0.5s
2:43.748Preston Pardus · fastest of 75 · top 5 within 1.0s
121.3Kyle Greenhill
+11.633squal +10.789s
107.6%qual 107.1%
2:43.994Hunter Phelps-Barron · fastest of 28 · top 5 within 0.6s
2:45.816Alex Scaler · fastest of 24 · top 5 within 1.5s
117.1Hunter Phelps-Barron
+13.701squal +12.574s
109.0%qual 108.3%
2:17.646Andrew Aquilante · fastest of 15 · top 5 within 3.7s
2:18.701Mark Boden · fastest of 14 · top 5 within 3.0s
158.8James Candelaria
-13.414squal -13.774s
91.2%qual 90.9%
32 rule changes (STL: 11, SM: 2, FV: 6, T1: 13)9 cars added · 5 engine · 5 tyres & wheels · 3 suspension & brakes · 2 aero · 1 weight · 6 wording · 1 other · SM allows aftermarket radiators in original location with stock OEM cooling fan, and permits 1990-1997 cars to install upper radiator seal NA75-50-OK7A. · SM rear brake caliper may use single bracket under upper retaining bolt head to prevent pin failure. · STL and STU clarify weight adjustment calculation order: engine adjustments first, then chassis percentage additions, subtractions, and fixed pounds. · STL STU rear wing Gurney flap terminology clarified from wicker to Gurney flap in mounting and chord rules. · T1 rear wing wording clarifies Gurney flap terminology in chord length and mounting height rules. · FV now permits 4 bolt wheels in addition to existing specifications. · FV now allows 4-bolt pattern wheels in addition to existing specifications. · GT3 and STU add Borg-Warner EFR6258 turbocharger to approved turbo lists. · STL adds Mazda MX-5 Global Cup 16-18 at 2450 lbs minimum and 2019 at 2550 lbs minimum. · STL Mazda MX-5 Club 06-15 allowed header part number 0000-06-5407-NC. · STL Acura/Honda B18 and B18C engines: restrictor sizes swapped, B18C1 removed from allowed variants. · T1 and T2 Corvettes now allow coilover suspension with 800 lb max coil springs; T1 Z06 conversion no longer T1-only. · STL Honda B18 loses 53mm restrictor requirement; B18C1 added with 54mm restrictor, B18C1 removed from other variants. · T1 Porsche 996 GT3 Cup eligible model years changed from 02-05 to 98-04. · T1 Chevrolet Corvette Cadillac XLR may install SCRSPLR-001 rear spoiler with OE bodywork. · T1 Camaro OEM 366mm rear rotor and caliper allowed without weight penalty. · STU GM Ecotech LNF now permitted without turbo, with LE5 head and intake manifold, meeting STL specs. · STL Mazda MZR restrictor reduced from 54 mm to 53 mm. · STL Mazda MZR restrictor reduces from 55 mm to 53 mm. · T1 Porsche 996 Spec Lines: 996 Cup Replica Rear deck lid now allowed. · T1 Acura NSX Turbo and Audi TTRS now require DOT tires per GCR section 9.3. · FV rain tyre changes to Hoosier #44266 22.5 x 5.0 x 15 WET or W3. · STL Mazda Spec MX5 Challenge adds approved wheel part numbers 0000-04-5706-GM, 0000-04-5706-SL to notes. · T1 BMW E46 and E36 models permitted with S54 engine; displacement corrected to 3250 cc from 3200 cc. · T1 adds Subaru WRX, WRX STI 2005-2020: 2457 cc, 3000 lbs minimum, 46 mm restrictor, alternate turbo permitted. · T1-LP Ford Mustang FP350S restrictor enlarged to 70mm; GT and GT5.0L weights increased to 3500 lbs, Brembo BBK at no penalty, restrictors removed from notes. · Ford Mustang/Thunderbird 5000 Coyote OEM added to T1; 2015-17 at 3450 lbs, 2018+ at 3450 lbs with 65mm flat plate restrictor. · T1 BMW M3 E92 (08-13) carbon dash allowed with 25 lb penalty added. · T1 Corvette C5 Z06, C6 coupe and Grand Sport, C6 Z06 may convert leaf springs to coilover suspension. · FV allows non-spec Hoosier tyres at Regional races only; Majors, Super Tour, and Runoffs require spec tyres from 1/1/2020. · Formula Vee now allows 22.5 x 5.5 x 15 rear tires on front axle; rain tire mandated as Hoosier #44266 22.5 x 5.0 x 15 from 1/1/2020. · FV wheels may now be 15-inch 4.5J steel VW with same 5-bolt pattern as standard 4J, within track limits.showhide
SM Radiator E&O Clarifications #29294wordingwordingSM allows aftermarket radiators in original location with stock OEM cooling fan, and permits 1990-1997 cars to install upper radiator seal NA75-50-OK7A.
SM Modifications to prevent failures of Rear Brake Caliper Pin #28953suspension & brakessuspension & brakesSM rear brake caliper may use single bracket under upper retaining bolt head to prevent pin failure.
STL Minimum Weight Determination #27695wordingwordingSTL and STU clarify weight adjustment calculation order: engine adjustments first, then chassis percentage additions, subtractions, and fixed pounds.
STL ST Gurney flap Wicker clarification #29012wordingwordingSTL STU rear wing Gurney flap terminology clarified from wicker to Gurney flap in mounting and chord rules.
FV Support for Recommended Item - 4 bolt wheels in FV #29084cars addedaddedFV now permits 4 bolt wheels in addition to existing specifications.
FV Support for 4-bolt pattern wheels #28955 #29118tyres & wheelsaddedtyres & wheelsFV now allows 4-bolt pattern wheels in addition to existing specifications.
STL Request for Addition to GT3 Approved Turbo List #27576cars addedaddedGT3 and STU add Borg-Warner EFR6258 turbocharger to approved turbo lists.
STL Request to add 2016-2019 GMX-5 Spec line #28604cars addedaddedSTL adds Mazda MX-5 Global Cup 16-18 at 2450 lbs minimum and 2019 at 2550 lbs minimum.
STL Request to update PN for MX-5 #28622cars addedaddedSTL Mazda MX-5 Club 06-15 allowed header part number 0000-06-5407-NC.
STL Correction - Clarification Honda/Acura B18B engine Letter # 26209 #28873wordingwordingSTL Acura/Honda B18 and B18C engines: restrictor sizes swapped, B18C1 removed from allowed variants.
T1 Consider coil spring conversion Corvette in T2 #28824suspension & brakesaddedsuspension & brakesT1 and T2 Corvettes now allow coilover suspension with 800 lb max coil springs; T1 Z06 conversion no longer T1-only.
STL STL Honda B18 restrictor changes #28794enginefasterengineSTL Honda B18 loses 53mm restrictor requirement; B18C1 added with 54mm restrictor, B18C1 removed from other variants.
T1 Additional Clarification on 996 Cup in T1 From Letter #28040 #28060cars addedaddedT1 Porsche 996 GT3 Cup eligible model years changed from 02-05 to 98-04.
T1 Request SPEC Corvette Rear Spolier #28182aeroaddedaeroT1 Chevrolet Corvette Cadillac XLR may install SCRSPLR-001 rear spoiler with OE bodywork.
T1 T1 Rear Brake Rotor Size Exemption for Gen 5 Camaro #28402cars addedaddedT1 Camaro OEM 366mm rear rotor and caliper allowed without weight penalty.
STL Change GM LNF 2.0 Allowance to LSJ Engine for Viable STL 2.0 #27884engineaddedengineSTU GM Ecotech LNF now permitted without turbo, with LE5 head and intake manifold, meeting STL specs.
STL Acura/Honda B18C engine chart. Reduce the current 54 mm flat plat #28663engineslowerengineSTL Mazda MZR restrictor reduced from 54 mm to 53 mm.
STL Mazda MZR engine chart. Reduce the current 55 mm flat plate to 53 #28664engineslowerengineSTL Mazda MZR restrictor reduces from 55 mm to 53 mm.
T1 Request 996 GT3 Trunk for Wing Allowance. #28153aeroaddedaeroT1 Porsche 996 Spec Lines: 996 Cup Replica Rear deck lid now allowed.
T1 All Touring, Change DOT Tire Language 9.1.9.1, 9.3.45 #28452wordingwordingT1 Acura NSX Turbo and Audi TTRS now require DOT tires per GCR section 9.3.
FV Update rain tire designation #28444tyres & wheelstyres & wheelsFV rain tyre changes to Hoosier #44266 22.5 x 5.0 x 15 WET or W3.
STL Request to add wheel part numbers #28342cars addedaddedSTL Mazda Spec MX5 Challenge adds approved wheel part numbers 0000-04-5706-GM, 0000-04-5706-SL to notes.
T1 Request for E46 wagon with S54 engine in T1 #27427enginefasterengineT1 BMW E46 and E36 models permitted with S54 engine; displacement corrected to 3250 cc from 3200 cc.
T1 Request to include Subaru WRX/STI 02-18 in T1 #24916cars addedaddedT1 adds Subaru WRX, WRX STI 2005-2020: 2457 cc, 3000 lbs minimum, 46 mm restrictor, alternate turbo permitted.
T1 Request Ford Mustang FP350S T1-LP weight and restrictor change #26662weight +100 lbsfasterweightT1-LP Ford Mustang FP350S restrictor enlarged to 70mm; GT and GT5.0L weights increased to 3500 lbs, Brembo BBK at no penalty, restrictors removed from notes.
T1 Request to classify Ford Coyote 3rd Gen OEM #27145cars addedaddedFord Mustang/Thunderbird 5000 Coyote OEM added to T1; 2015-17 at 3450 lbs, 2018+ at 3450 lbs with 65mm flat plate restrictor.
T1 Request alternate dashboard #27276otheraddedT1 BMW M3 E92 (08-13) carbon dash allowed with 25 lb penalty added.
T1 Request for Allowance of Coil Springs on Limited Prep C6 Corvette #27713suspension & brakesaddedsuspension & brakesT1 Corvette C5 Z06, C6 coupe and Grand Sport, C6 Z06 may convert leaf springs to coilover suspension.
FV FV Allow non-spec tire in Regional competition #26284tyres & wheelsaddedtyres & wheelsFV allows non-spec Hoosier tyres at Regional races only; Majors, Super Tour, and Runoffs require spec tyres from 1/1/2020.
FV Request to Allow Rear Tires on the Front of Formula Vee #26537tyres & wheelsaddedtyres & wheelsFormula Vee now allows 22.5 x 5.5 x 15 rear tires on front axle; rain tire mandated as Hoosier #44266 22.5 x 5.0 x 15 from 1/1/2020.
FV Clarification on Wheel Bolt Pattern #27603tyres & wheelsaddedtyres & wheelsFV wheels may now be 15-inch 4.5J steel VW with same 5-bolt pattern as standard 4J, within track limits.
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
2:14.552Todd Buras · fastest of 60 · top 5 within 0.2s
2:16.459Elivan Goulart · fastest of 56 · top 5 within 0.4s
119.8Jim Drago
+9.186squal +7.349s
107.2%qual 105.8%
2:15.712Andrew Whitston · fastest of 26 · top 5 within 1.5s
2:18.289Zachary Whitston · fastest of 19 · top 5 within 0.4s
114.8Roger Siebenaler
+11.016squal +8.509s
108.7%qual 106.7%
1:54.771Andrew Aquilante · fastest of 19 · top 5 within 3.1s
2:14.413Andrew Aquilante · fastest of 15 · top 5 within 4.8s
156.2Mark Boden
+7.140squal -12.432s
105.6%qual 90.2%
40 rule changes (STL: 11, SM: 4, FV: 6, T1: 19)9 cars added · 6 weight · 3 engine · 3 suspension & brakes · 1 aero · 1 induction · 1 tyres & wheels · 12 wording · 4 other · FV exhaust exit opening repositioned: minimum one inch, maximum four inches behind rear body. · STL adds Mazda Spec MX-5 Challenge, 2000cc displacement, 2500 lb minimum weight, with mandatory Roush, Penske, Eibach, and other specified components. · FV allows fifteen-inch steel wheels at 4J or 4.5J width, standard VW sedan or within track dimensions. · T1-LP Chevrolet Camaro 1LE 2016+ minimum weight reduced to 3500 lbs, restrictor increased to 70mm. · Ford Mustang Challenge added to T1 as E&O with 4600cc displacement, 3300 lbs minimum weight, no restrictor. · T1 Chevrolet Corvette Cadillac XLR model year range removed from specification. · STU allows alternate intake manifolds on case-by-case basis; stock throttle device and manifold otherwise required. · T1 Cadillac CTS/CTS-V, Chevrolet Camaro, Pontiac Firebird and GTO intake restrictor increases from 67 mm to 70 mm. · FV exhaust outlet opening max distance from body rear increased from 3 to 4 inches. · STL Acura/Honda B18 except C engine restrictor increased from 53mm to 54mm flat plate. · T2-T4 touring tires must be DOT certified with minimum U speed rating; TCS line size is maximum unless noted. · FV front track maximum 52.500 inches; rear track 49.125–50.750 inches; spacers now allowed. · STL and STU ride height measurement clarified: lowest rocker panel point without driver, excluding pinch weld. · Ford Mustang with 3.5 EcoBoost engine added to T1: 3496 cc displacement, 3300 lb minimum weight, 31 mm restrictor. · T1 Corvette C5 body allowed C7 carbon aero parts, adds fifty pounds. · T1 Audi TTRS must conform to July 24th, 2015 revision 7 GTS rules, not December 14th, 2011 revision 3. · T1 minimum ride height set to 3.5 inches, measured at rocker panel without driver. · T1 Porsche 928 S4/GTS-R minimum weight drops from 3500 to 3200 lbs; 60mm flat plate restrictor removed. · FV disc brake assembly minimum weight clarified to 16.5 lbs total; caliper minimum weight requirement of 1.65 lbs removed. · Porsche 928 S4/928 GTS-R added to T1 at 5400cc, 3500 lbs minimum, 60mm restrictor. · SM fuel pump and filter now permitted as Mazda or OEM equivalent part. · STL adds VW 1.8L R4 20VT 1781 cc, 1781 minimum weight, naturally aspirated only. · STL Mazda Renesis minimum weight reduced to 2700 lbs. · STL Mazda MX-5 Cup brake pad compound now open. · STL adds Acura/Honda B18C1 GSR with 1797cc displacement, 54mm flat plate restrictor required, porting outside 1" allowance prohibited. · STL Mazda 12 and 13B now permit port matching; porting ban removed. · T1-LP Ford Mustang GT 5.0L 2018- classified at 3400 lbs with 65mm restrictor, T2 and T3 Mustangs limited to 2015-2017. · FV intake manifold horizontal tube measurement location clarified; removed specific distance ranges from rule text. · SM allows factory Mazda ECU and injector harnesses (P/N 0000-10-020E-99, 0000-10-080D-99) on 1999–2000 model year cars, unmodified. · SM electrical rules reorganized and clarified; alternator now externally regulated only by OEM ECU or master kill switch; harness repair by splicing permitted. · SM tire tread protrusion language removed from GCR 9.1.7.C.5. · STL B17 now requires 54mm flat plate restrictor; B18C Type R variants move to 54mm restrictor, weight chart baseline. · STL Mazda Miata removes maximum displacement limit; minimum weight corrected to unspecified figure. · T1-LP Mustang GT350(R) spec line replaced with complete dimensions, gearing, brakes, weight 3650 lbs curb, carbon wheels standard. · Ford Mustang FP350S (2017) classified in T1-LP with 3600 lbs minimum weight, 18×11 wheels, 315 tires, 6-speed gears. · T1 suspension rules clarified: spherical bearings, solid or spherical bushings, and alternate control arms now permitted. · T1 Porsche 996 and 996 GT3 Cup lose 150–200 lbs to 3000; 997 loses 50 lbs to 3100. · Porsche 997 T1 Maximum gains PDK transmission option; GT3 Cup engine remains not allowed. · T1 Acura NSX Turbo World Challenge weight rises to 3100 lbs, restrictor shrinks to 44mm. · T1–T4 spec car classifications clarified with permitted parts, rule conformance versions, and exclusions of other touring modifications.showhide
FV Allowed Modifications E&O #27398wordingwordingFV exhaust exit opening repositioned: minimum one inch, maximum four inches behind rear body.
STL Request to Classify Spec MX-5 Challenge in STL #27399cars addedaddedSTL adds Mazda Spec MX-5 Challenge, 2000cc displacement, 2500 lb minimum weight, with mandatory Roush, Penske, Eibach, and other specified components.
FV E&O Wheels #27230tyres & wheelsaddedtyres & wheelsFV allows fifteen-inch steel wheels at 4J or 4.5J width, standard VW sedan or within track dimensions.
T1 T1 LP 2016 Camaro and Later #27198weight -100 lbsfasterweightT1-LP Chevrolet Camaro 1LE 2016+ minimum weight reduced to 3500 lbs, restrictor increased to 70mm.
T1 Request to return Ford Mustang Challenge Car to T1 #26751cars addedaddedFord Mustang Challenge added to T1 as E&O with 4600cc displacement, 3300 lbs minimum weight, no restrictor.
T1 Correct years in T1 FP Corvette spec #27023wordingwordingT1 Chevrolet Corvette Cadillac XLR model year range removed from specification.
STL Request clarification for manifold and throttle in STU #27004wordingwordingSTU allows alternate intake manifolds on case-by-case basis; stock throttle device and manifold otherwise required.
T1 Request BoP Baten - T1 Camaro - Follow up to Letter # 26145 #26900inductionfasterinductionT1 Cadillac CTS/CTS-V, Chevrolet Camaro, Pontiac Firebird and GTO intake restrictor increases from 67 mm to 70 mm.
FV Exhaust termination rule E&O #26702wordingwordingFV exhaust outlet opening max distance from body rear increased from 3 to 4 inches.
STL Request Restrictor Plate correction #26779enginefasterengineSTL Acura/Honda B18 except C engine restrictor increased from 53mm to 54mm flat plate.
T1 Clarify DOT tires touring #26556wordingwordingT2-T4 touring tires must be DOT certified with minimum U speed rating; TCS line size is maximum unless noted.
FV E&O Dimensions #26674suspension & brakessuspension & brakesFV front track maximum 52.500 inches; rear track 49.125–50.750 inches; spacers now allowed.
STL Request Ride Height Clarification #26597wordingwordingSTL and STU ride height measurement clarified: lowest rocker panel point without driver, excluding pinch weld.
T1 Request to Classify EcoBoost Mustang #25841cars addedaddedFord Mustang with 3.5 EcoBoost engine added to T1: 3496 cc displacement, 3300 lb minimum weight, 31 mm restrictor.
T1 Request Corvette aerodynamic aids #26265aerosloweraeroT1 Corvette C5 body allowed C7 carbon aero parts, adds fifty pounds.
T1 Audi TTRS VTS Documentation Revision #26578wordingwordingT1 Audi TTRS must conform to July 24th, 2015 revision 7 GTS rules, not December 14th, 2011 revision 3.
T1 Request Ride Height Clarification #26599suspension & brakessuspension & brakesT1 minimum ride height set to 3.5 inches, measured at rocker panel without driver.
T1 Opposes Unfair weight and throttle restrictor #26719weight -300 lbsfasterweightT1 Porsche 928 S4/GTS-R minimum weight drops from 3500 to 3200 lbs; 60mm flat plate restrictor removed.
FV Request to clarify Disc Brake rules bearing retainer & weights #26262weightslowerweightFV disc brake assembly minimum weight clarified to 16.5 lbs total; caliper minimum weight requirement of 1.65 lbs removed.
T1 Request to classify the Porsche 928GTS/S4 in Touring 1 #26315cars addedaddedPorsche 928 S4/928 GTS-R added to T1 at 5400cc, 3500 lbs minimum, 60mm restrictor.
SM Request to allow aftermarket fuel filters. #26370otheraddedSM fuel pump and filter now permitted as Mazda or OEM equivalent part.
STL Request to reduce weight of RX8 with Renesis rotary #25781weight -100 lbsfasterweightSTL Mazda Renesis minimum weight reduced to 2700 lbs.
STL Request for Open Brake Pads On Mazda MX-5 Cup NC #25821otheraddedSTL Mazda MX-5 Cup brake pad compound now open.
STL Request to clarify B18C1 GSR Honda B motor table #26209cars addedaddedSTL adds Acura/Honda B18C1 GSR with 1797cc displacement, 54mm flat plate restrictor required, porting outside 1" allowance prohibited.
STL Port Matching #26415enginefasterengineSTL Mazda 12 and 13B now permit port matching; porting ban removed.
T1 Request Mustang GT Limited Prep 2018 Classification #24431cars addedaddedT1-LP Ford Mustang GT 5.0L 2018- classified at 3400 lbs with 65mm restrictor, T2 and T3 Mustangs limited to 2015-2017.
FV FV Intake Manifold Clarification #26008wordingwordingFV intake manifold horizontal tube measurement location clarified; removed specific distance ranges from rule text.
SM Request 99-00 replacement Wire harnesses #25602otheraddedSM allows factory Mazda ECU and injector harnesses (P/N 0000-10-020E-99, 0000-10-080D-99) on 1999–2000 model year cars, unmodified.
SM Organize and Clarify 9.1.7.C.1.o. #25913wordingwordingSM electrical rules reorganized and clarified; alternator now externally regulated only by OEM ECU or master kill switch; harness repair by splicing permitted.
SM Strike Tire Tread Language #26123wordingremovedSM tire tread protrusion language removed from GCR 9.1.7.C.5.
STL Request to equalize FPR Reduction on all B-Series Vtec Engines #24746enginefasterengineSTL B17 now requires 54mm flat plate restrictor; B18C Type R variants move to 54mm restrictor, weight chart baseline.
STL Request E&O for Mazda Miata Spec Line #25955otherunclearSTL Mazda Miata removes maximum displacement limit; minimum weight corrected to unspecified figure.
T1 Class 2015+ Mustang GT350(R) #21466wordingwordingT1-LP Mustang GT350(R) spec line replaced with complete dimensions, gearing, brakes, weight 3650 lbs curb, carbon wheels standard.
T1 Request to Classify Ford FP350S in T1-LP #25341cars addedaddedFord Mustang FP350S (2017) classified in T1-LP with 3600 lbs minimum weight, 18×11 wheels, 315 tires, 6-speed gears.
T1 Amendment to Request #25555 #25556suspension & brakessuspension & brakesT1 suspension rules clarified: spherical bearings, solid or spherical bushings, and alternate control arms now permitted.
T1 Request to balance 996 v 997 T1 weight #25658weightfasterweightT1 Porsche 996 and 996 GT3 Cup lose 150–200 lbs to 3000; 997 loses 50 lbs to 3100.
T1 Request to Add PDK Transmission to 997 Porsche Spec Line #25668cars addedaddedPorsche 997 T1 Maximum gains PDK transmission option; GT3 Cup engine remains not allowed.
T1 T1 World Challenge/Grand AM Spec Cars #25687weightslowerweightT1 Acura NSX Turbo World Challenge weight rises to 3100 lbs, restrictor shrinks to 44mm.
T1 Add Clarification to Spec Car Classifications Vehicle Spec #25774wordingwordingT1–T4 spec car classifications clarified with permitted parts, rule conformance versions, and exclusions of other touring modifications.
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.