Quickest here:STU 1:59.948 Kevin Boehm, Runoffs 2019 qualifying · GT3 1:57.135 Jeff Dernehl, Runoffs 2022 qualifying
STUGT3solid race · dashed qualifying · slower is lower
STUGT3solid race · dashed qualifying · each class's best lap as a share of STU's at the same event (the reference class, changeable above); 100% is level, higher is quicker
Event
STU
GT3
Qual best
Race best
Trap
Qual best
Race best
Trap
vs STU
% of STU
Runoffs 2023 ROFF232023-09-23
2:02.302Mark Liller · fastest of 14 · top 5 within 1.6s-30.055s (-19.73%)
144.0Mark Liller+0.1 mph (+0.1%)
1:59.872Tony Ave · fastest of 8 · top 5 within 3.9s-24.475s (-16.96%)
145.8Jeff Dernehl-3.6 mph (-2.4%)
-2.430s
98.0%
13 rule changes (STU: 3, GT3: 10)4 cars added · 2 engine · 2 induction · 1 removed · 1 tyres & wheels · 1 weight · 2 wording · GT3 cars using 15" American Racer 23.5-10.0-15 bias ply tires avoid weight penalty. · Toyota GR Cup and GR86 Cup (2022-) newly classified in STU at 2700 lbs with 2387 cc engine. · Fields Cardinal V8 classified in GT1 with Ford V8 engine, 4.9L displacement, 2100 lbs minimum weight. · STU Mazda BP5A classified at 1839 cc maximum displacement, 2023-04-01. · STU minimum weight chart updated: 2450cc to 2595lbs, 2600cc to 2710lbs. · GT3 Nissan VG30 engine removed from class entirely. · GT3 normally aspirated cars may use intake chokes instead of SIRs, fitted to each carburetor barrel, same size as required SIR. · GT3 2.0L 4-valve non-turbo engines may run unrestricted at 2060 lbs instead of with a choke restriction. · GT3 Mazda BP4W Turbocharged OEM engine added at 2060 lbs with 34mm TIR and IHI RHF5 VJ35 turbocharger. · GT2 TA2 and GTA throttle body part numbers updated to GM 90mm electronic #12570790 or Edelbrock 90mm mechanical #33869 or #3870. · GT3 Nissan SR20VET turbo changes to GT2860RS and allows open ECU instead of OEM stock. · GT3 adds 84-87 Civic 3dr FWD, hood bulge allowed, no openings. · GT3 Turbo maximum displacement increases from 1800 cc to 1850 cc.showhide
GT3 Addendum to letter 33913, GT3 DOT tires. #34627tyres & wheelsfasterGT3 cars using 15" American Racer 23.5-10.0-15 bias ply tires avoid weight penalty.
STU 2022 Toyota GR Cup for STU #34449cars addedneutralToyota GR Cup and GR86 Cup (2022-) newly classified in STU at 2700 lbs with 2387 cc engine.
GT3 Please classify Fields Cardinal V8 #33784cars addedneutralFields Cardinal V8 classified in GT1 with Ford V8 engine, 4.9L displacement, 2100 lbs minimum weight.
STU Alternate OEM Miata Intake Manifold #33827wordingneutralSTU Mazda BP5A classified at 1839 cc maximum displacement, 2023-04-01.
STU E&O STU NA Weight Chart. #33737weightfasterSTU minimum weight chart updated: 2450cc to 2595lbs, 2600cc to 2710lbs.
GT3 Remove Nissan VG30 engine from GT3 #33609removedneutralGT3 Nissan VG30 engine removed from class entirely.
GT3 GT3 Choke option effective 1-01-2023 #33669inductionneutralGT3 normally aspirated cars may use intake chokes instead of SIRs, fitted to each carburetor barrel, same size as required SIR.
GT3 GT3 2.0L choke/weight option #33670inductionfasterGT3 2.0L 4-valve non-turbo engines may run unrestricted at 2060 lbs instead of with a choke restriction.
GT3 Turbocharged Engine Rules #33145cars addedneutralGT3 Mazda BP4W Turbocharged OEM engine added at 2060 lbs with 34mm TIR and IHI RHF5 VJ35 turbocharger.
GT3 GT2 (TA2)/GTA Part Number Update #33315wordingneutralGT2 TA2 and GTA throttle body part numbers updated to GM 90mm electronic #12570790 or Edelbrock 90mm mechanical #33869 or #3870.
GT3 GT3 Nissian SR20VET unrestricted ECU change #33432enginefasterGT3 Nissan SR20VET turbo changes to GT2860RS and allows open ECU instead of OEM stock.
GT3 GT3 Turbo Displacement Clarification #32952enginefasterGT3 Turbo maximum displacement increases from 1800 cc to 1850 cc.
Runoffs 2022 ROFF222022-09-24
2:00.615Johan Schwartz · fastest of 21 · top 5 within 2.6s+0.667s (+0.56%)
2:32.357Mark Liller · fastest of 19 · top 5 within 4.3s+31.874s (+26.46%)
143.9Johan Schwartz+0.1 mph (+0.1%)
1:57.135Jeff Dernehl · fastest of 13 · top 5 within 3.2s-1.059s (-0.90%)
2:24.347Tony Ave · fastest of 12 · top 5 within 8.2s+25.302s (+21.25%)
149.5Jeff Dernehl-0.2 mph (-0.1%)
-8.010squal -3.480s
94.7%qual 97.1%
90 rule changes (STU: 50, GT3: 40)21 cars added · 11 induction · 10 engine · 9 weight · 4 aero · 3 tyres & wheels · 32 wording · GT taillights may now be original style or a panel graphic with functioning red LED brake lamps; wording change only. · GT3 Nissan SR20VET Limited Prep-Turbocharged OEM engine classified, 1998cc DOHC with Garrett GT2560LS turbo, 2060 lbs. · STU Mazda 13B Turbo classified, streetport only, stock turbos prohibited, alternatives allowed. · STU OEM louver vents now exempt from vent count and 200 square inch allowance. · STU 2400cc non-4-valve engines gain 9% base weight reduction; DI turbo prep limits removed. · GT3 Fiat 124 Spider model name corrected from Pininfarina to Pininfarina Spider. · STU normally-aspirated 2976–3200 cc single-throttle engines lose 10% base engine weight reduction. · ST redundant language removed from balance shaft and pulley modification rules. · GT3 Fiat 124 Spider Pininfarina reclassified by model year, body style, drivetrain, and wheelbase. · GT3 cars can use up to 18" wheels with 12.0" tire cross section and 26.0" diameter at 5% weight penalty, down from 8%. · STU cars that qualified for 9 inch wheels in 2021 may continue through 2022 only. · STU splitter definition clarified: must be single-plane with no vertical deviations, attached to lowest front point. · GT3-TCR: Audi RS3 LMS SEQ power to 90%, weight to 3177 lbs; RS3 LMS DSG power to 90%; Honda Civic Type R power to 90%, weight to 3210 lbs; Hyundai i30N power to 90%, weight to 3254 lbs; VW Golf GTI SEQ power to 90%, weight to 3177 lbs; Gol… · STU BMW S52B32 minimum weight drops 90 lbs to 3110; max displacement cut to 3152 cc. · STU BMW S50B32 Euro classified at 3201 cc displacement, 3300 lbs minimum weight. · ST engine swap origin country requirement changes from North America to the United States for case-by-case approval. · STU Honda CRX (84-91) and Civic Del Sol (93-97) ineligible for front wheel drive weight reductions. · STU vehicles at or over 2950 lbs base weight may use 9 inch wide wheels instead of 8.0 inch maximum. · STU minimum weights reduced: 2450cc to 2596 lbs, 2500cc to 2635 lbs, 2550cc to 2675 lbs. · GT3 Ginetta G40 classified with Mazda MZR 1999cc at 2060 lbs or Ford Duratec 2260cc at 2195 lbs. · GT3 Mazda MZR DOHC 1999cc classified with 2195 lbs minimum weight, unrestricted fuel induction. · Volvo S60 2000-2009 classified in GT3. · GT3 2.0L 4V engines now unrestricted at 2195 lbs minimum weight across all makes. · GT3 wing wording corrected: single element airfoil scaled changed to up to maximum chord 10.75 inches. · STU normally aspirated engines: minimum weights reduced up to 310 lbs; single throttle body weight reduction removed. · STU Audi A4 1.8T minimum weight fixed at 3050 lbs, VF30 turbo with 35mm restrictor now required only. · STL and STU Improved Touring vehicles must conform to 9.1.4 Tires & Wheels requirements. · GT3 adds Fiat Spider 2000, Years 79-81, RWD, 89.76" wheelbase. · GT3 adds Fiat X-19, years 72-89. · STU engines may delete balance shafts and plug openings; alternate pulleys allowed for timing belt or chain operation only. · STU hood vents allowed to include louvers within 200 sq. inch area. · STU adds Honda K23 with 2354cc displacement and minimum weight per chart, K24 block allowed with K23 internals and head. · STU Honda K23 internals rule relaxed to require only K23 crankshaft, allowing other internal modifications. · STL and STU piston engines clarified: intake manifold and cylinder head porting remains free. · GT3 Fun Cup Beetle Sealed weight reduced 210 lbs, to 1850. · GT3-TCR class added: Audi RS3 LMS, Honda Civic Type R, Hyundai i30N, VW Golf GTI at 3100–3200 lbs with 200 tread wear tires. · GT3 Ford Cortina GT 1964-1968 newly classified for competition. · GT3 Fun Cup Beetle EVO3 classified with 1984 cc sealed SOHC engine, 2060 lbs minimum weight. · GTA part numbers updated: 0-80541-1 to 0-80541-2 in two sections and 6010 to 6014X in TA2 Appendix. · GT3 now permits current FP spec line cars to compete while maintaining their full FP rule set. · STU fender flare wording clarified: exterior contour of any wheel opening may not change opening size, location or shape from side view. · STU Mazda 12A Bridge Port Miata weight reduced from 2550 lbs to 2350 lbs. · GT3 Mazda MZR 2.0L fuel induction restrictor increases from 31 to 32 mm. · GT3 Mazda Renesis and 13B Bridgeport choke reduced from 44mm to 42mm. · STU fender flare rules clarified: maximum 2 inches, must cover tire contact patch from above, cannot alter body configuration or wheel opening geometry. · STU Honda S2000 allows F20/F22 K24 crankshaft with chart weight for achieved displacement. · ST oil coolers and filters now explicitly allowed to be added or substituted; wording clarifies existing permissions. · STL/STU 90-05 Mazda Miata gains approval for Mazda Motorsports Development alternate front wheel hubs. · ST cars may relocate ABS actuation hardware and wiring anywhere in engine compartment. · STU Porsche PDK automatic transmission limited to 8 forward speeds instead of torque converter restriction. · STU Mazda 13B Street Port 2400 removes choke location restriction, allows auto-type 2bbl with dual-Y manifold. · STU driveshaft and half-shaft materials change from OEM-type to steel or aluminum. · STU Mazda 13B Street Port classified at 2400 lbs minimum weight, replacing peripheral and bridge port variants. · GT3 Mazda MZR and MZR/L5-VE fuel induction sizing changes from 31 to 32. · GT3 Honda Prelude 1992-1997 classified, 2dr FWD, 104 inch wheelbase. · ST aero devices and reference areas now include end plates but exclude fasteners protruding over 1/2 inch. · GT1, GT2, GT3, GTL, GTX now permit turbocharging/supercharging if listed on spec line. · STU fender flare rules reworded: up to 2" per corner allowed with 1% weight penalty total. · STL and STU clarify weight adjustment calculation order: engine adjustments first, then chassis adjustments. · STL and STU rear wing rules clarify that wicker is a Gurney flap; no performance change. · GT3 Mazda 12A Peripheral Port added to rule set, 2300 cc, 2292 lbs. · TA2 Gurney flap wording clarified: terminology standardized to 'Gurney flap', height limits and thickness specifications remain 0.50 inch / 0.625 inch or 0.375 inch / 0.0625 inch depending on configuration. · STO rear wing wording clarified: 'wicker' changed to 'Gurney flap' in maximum chord and mounting height rules. · GT classes clarify Gurney flap wording, replacing wickerbill/tab terminology with flap; specifications unchanged. · GT3 4v SIR 4-cylinder engines across multiple brands increase fuel induction from 31 to 32. · GT3 and STU add Borg-Warner EFR6258 to approved turbocharger list. · STU request for alternate intake manifold denied; no rule change issued. · GT3 and STU add Borg-Warner EFR6258 to approved turbocharger list. · STU large displacement turbo engines limited by GCR turbo list; non-turbo trim suggested as more competitive. · STU sequential shifters referred to Board of Directors for approval; no change implemented yet. · GT3 Nissan KA24E loses permission to use 32mm chokes at 2280 lbs for 2011-2012 only. · STU Mazda 13B Bridge Port and Street Port engines added with 2550 and 2250 lbs minimum weights respectively. · STU Honda S2000 adds HKS Supercharger kits 12001-AH006 and 12001-AH010 as allowed. · STU Lotus Elise Cup R and SC models, plus Exige SC, gain 100–200 lbs minimum weight. · STU Volkswagen GTI/GLI MK5 and Jetta Mk4 may install turbo inlet restrictor in OEM turbo inlet housing. · STU Honda K20C1 Turbo I4 restrictor reduces from 36mm to 35mm. · STU GM Ecotech LNF now allowed with turbo removed or with LE5 head and intake manifold, meeting STL specs. · STU Porsche 944 now permits VW/Audi 1.8L and 2.0L turbo engines as alternates. · GT3 Mazda MZR L5-VE gets 31mm SIR restrictor, weight up from 1950 to 2195 lbs, direct injection banned. · STU vehicles over 2951 lbs base weight may use 9 inch wide wheels, up from 2950 lbs. · STU turbocharged engines now use base weight instead of minimum weight, with 3% DI increase applied to base weight. · GT1, GT2, GT3, GTL, GTX may omit windshield clips if factory glass is bonded per original specifications. · Factory Five Type 65 Coupe R with Ford 302/351 or 5.0/5.2L NA added to GTX-MISC at 2600 lbs. · GT3 Mazda 13B Bridgeport restrictor reduced from 44mm to 42mm. · GT3 Alfa Romeo 4C classified with 1742cc engine, 33mm TIR restrictor, 2325 lbs minimum weight. · GT3 Mazda MZR/L5-VE gets unrestricted induction, drops 245 lbs to 1950, limited to GT2 prep. · GT3 Honda K20C1 turbocharged engine added with 33 mm TIR restrictor, 2350 lbs minimum weight. · GT3 wing end plates change from 11.00 by 4.00 inches rectangle to maximum 64 square inches. · GT3 Nissan adds SR16VE engine, 1596cc, 1690 lbs, unrestricted induction. · STU cars with manual OEM throttle bodies may convert to OEM electronic throttle body of same inner diameter.showhide
GT3 Tail lights on all GT category race cars. #32799wordingneutralGT taillights may now be original style or a panel graphic with functioning red LED brake lamps; wording change only.
STU Request Mazda 13 B turbo #32668cars addedneutralSTU Mazda 13B Turbo classified, streetport only, stock turbos prohibited, alternatives allowed.
STU Hood Vents and Intercooler Scoops #32733aerofasterSTU OEM louver vents now exempt from vent count and 200 square inch allowance.
STU Non 4 valve weight reduction removed #32808enginefasterSTU 2400cc non-4-valve engines gain 9% base weight reduction; DI turbo prep limits removed.
GT3 Correct Model GT3 - Fiat #32776wordingneutralGT3 Fiat 124 Spider model name corrected from Pininfarina to Pininfarina Spider.
STU Error in new minimum weight table when combined with other text #32711engineslowerSTU normally-aspirated 2976–3200 cc single-throttle engines lose 10% base engine weight reduction.
STU Redundant Language in May GCR #32713wordingneutralST redundant language removed from balance shaft and pulley modification rules.
GT3 Correct Fiat Spider Years #32149wordingneutralGT3 Fiat 124 Spider Pininfarina reclassified by model year, body style, drivetrain, and wheelbase.
GT3 wheel size addition #32247tyres & wheelsfasterGT3 cars can use up to 18" wheels with 12.0" tire cross section and 26.0" diameter at 5% weight penalty, down from 8%.
STU Opposed to the Proposed STU Weight Chart #32381wordingneutralSTU cars that qualified for 9 inch wheels in 2021 may continue through 2022 only.
STU Clarification request for GCR 9.1.4.D.3.a Splitter Definition #32414wordingneutralSTU splitter definition clarified: must be single-plane with no vertical deviations, attached to lowest front point.
GT3 GT3 TCR Car Feedback #31677engine +2 lbsslowerGT3-TCR: Audi RS3 LMS SEQ power to 90%, weight to 3177 lbs; RS3 LMS DSG power to 90%; Honda Civic Type R power to 90%, weight to 3210 lbs; Hyundai i30N power to 90%, weight to 3254 lbs; VW Golf GTI SEQ power to 90%, weight to 3177 lbs; Gol…
STU Request Adjustment to Min Weight for STU BMW E36 M3 (95-99) #31535weight -90 lbsfasterSTU BMW S52B32 minimum weight drops 90 lbs to 3110; max displacement cut to 3152 cc.
STU BMW E36 M3 Canadian (North American) S50B32 engine #31866cars addedneutralSTU BMW S50B32 Euro classified at 3201 cc displacement, 3300 lbs minimum weight.
STU Engine Swap Origin Country #32209wordingneutralST engine swap origin country requirement changes from North America to the United States for case-by-case approval.
STU CRX/Civic Del Sol #32214weightslowerSTU Honda CRX (84-91) and Civic Del Sol (93-97) ineligible for front wheel drive weight reductions.
STU Error correction #32383tyres & wheelsfasterSTU vehicles at or over 2950 lbs base weight may use 9 inch wide wheels instead of 8.0 inch maximum.
STU Single TB Weight Modifiers Add to Chart #32393weightfasterSTU minimum weights reduced: 2450cc to 2596 lbs, 2500cc to 2635 lbs, 2550cc to 2675 lbs.
GT3 Request to Classify Ginetta G40 in GT3 #31598cars addedneutralGT3 Ginetta G40 classified with Mazda MZR 1999cc at 2060 lbs or Ford Duratec 2260cc at 2195 lbs.
GT3 Volvo S60 in GT3 #31970cars addedneutralVolvo S60 2000-2009 classified in GT3.
GT3 GT3 2.0L 4V engines now unrestricted. #32190enginefasterGT3 2.0L 4V engines now unrestricted at 2195 lbs minimum weight across all makes.
GT3 TB correction to wing wording #32191wordingneutralGT3 wing wording corrected: single element airfoil scaled changed to up to maximum chord 10.75 inches.
STU Single TB Weight Modifiers #31449weightfasterSTU normally aspirated engines: minimum weights reduced up to 310 lbs; single throttle body weight reduction removed.
STU Request to Remove A4 1.8t from STU Spec Line Tables #31465weightslowerSTU Audi A4 1.8T minimum weight fixed at 3050 lbs, VF30 turbo with 35mm restrictor now required only.
STU Improved Touring Tires #32063tyres & wheelsneutralSTL and STU Improved Touring vehicles must conform to 9.1.4 Tires & Wheels requirements.
GT3 Request to add Fiat to GT3 CARS #31803cars addedneutralGT3 adds Fiat Spider 2000, Years 79-81, RWD, 89.76" wheelbase.
GT3 Request to add Fiat to GT3 CARS #31804cars addedneutralGT3 adds Fiat X-19, years 72-89.
STU Request Allowance for Balance Shaft Delete in STU #31434enginefasterSTU engines may delete balance shafts and plug openings; alternate pulleys allowed for timing belt or chain operation only.
STU Request Louvers in hood vents #31916aeroneutralSTU hood vents allowed to include louvers within 200 sq. inch area.
STU Request to Add Honda K23 Spec Line #30682cars addedneutralSTU adds Honda K23 with 2354cc displacement and minimum weight per chart, K24 block allowed with K23 internals and head.
STU RE: Aug FT letter 30682 #31060enginefasterSTU Honda K23 internals rule relaxed to require only K23 crankshaft, allowing other internal modifications.
STU Throttling Device Clarification #31323wordingneutralSTL and STU piston engines clarified: intake manifold and cylinder head porting remains free.
GT3 31032 correction to weight #31525weight -210 lbsfasterGT3 Fun Cup Beetle Sealed weight reduced 210 lbs, to 1850.
GT3 Add TCR cars to GT3 #31540cars addedneutralGT3-TCR class added: Audi RS3 LMS, Honda Civic Type R, Hyundai i30N, VW Golf GTI at 3100–3200 lbs with 200 tread wear tires.
GT3 Please approve 1964-1968 Ford Cortina GT for competition in GT# #30941cars addedneutralGT3 Ford Cortina GT 1964-1968 newly classified for competition.
GT3 Request car classification #31032cars addedneutralGT3 Fun Cup Beetle EVO3 classified with 1984 cc sealed SOHC engine, 2060 lbs minimum weight.
GT3 Request to Update GTA Obsolete Part Numbers #30615wordingneutralGTA part numbers updated: 0-80541-1 to 0-80541-2 in two sections and 6010 to 6014X in TA2 Appendix.
GT3 Request to Permit FP cars in GT3 #30611cars addedneutralGT3 now permits current FP spec line cars to compete while maintaining their full FP rule set.
STU STU Fender flares #30696wordingneutralSTU fender flare wording clarified: exterior contour of any wheel opening may not change opening size, location or shape from side view.
STU Request weight reduction for 12A bridgeport motor in Miata #30751weight -200 lbsfasterSTU Mazda 12A Bridge Port Miata weight reduced from 2550 lbs to 2350 lbs.
GT3 Mazda MZR 2.0L Engine #30455inductionfasterGT3 Mazda MZR 2.0L fuel induction restrictor increases from 31 to 32 mm.
GT3 Disfranchised GT3 Mazda, correct choke size #30570inductionslowerGT3 Mazda Renesis and 13B Bridgeport choke reduced from 44mm to 42mm.
STU Request for Fender Flare Clarification #30375wordingneutralSTU fender flare rules clarified: maximum 2 inches, must cover tire contact patch from above, cannot alter body configuration or wheel opening geometry.
STU Provision for Interchangeable Engine Components Already Allowed #30342engineunclearSTU Honda S2000 allows F20/F22 K24 crankshaft with chart weight for achieved displacement.
STU ST Oil Coolers E&O Correction to 9.1.4.2.H #30388wordingneutralST oil coolers and filters now explicitly allowed to be added or substituted; wording clarifies existing permissions.
STU Super Touring Alternate Miata Hubs #30345wordingneutralSTL/STU 90-05 Mazda Miata gains approval for Mazda Motorsports Development alternate front wheel hubs.
STU Brake Component Relocation #29990wordingneutralST cars may relocate ABS actuation hardware and wiring anywhere in engine compartment.
STU Porsche PDK #30081wordingneutralSTU Porsche PDK automatic transmission limited to 8 forward speeds instead of torque converter restriction.
STU Reference Letter #29333 Proposed STU 13B Spec Line Changes #30086inductionfasterSTU Mazda 13B Street Port 2400 removes choke location restriction, allows auto-type 2bbl with dual-Y manifold.
STU Drive Shaft Request #30087wordingneutralSTU driveshaft and half-shaft materials change from OEM-type to steel or aluminum.
STU 13B Rules Adjustment #29333cars addedslowerSTU Mazda 13B Street Port classified at 2400 lbs minimum weight, replacing peripheral and bridge port variants.
GT3 Mazda MZR SIR Sizing #29555inductionfasterGT3 Mazda MZR and MZR/L5-VE fuel induction sizing changes from 31 to 32.
GT3 Request to Classify 1992-1997 Honda Prelude #29687cars addedneutralGT3 Honda Prelude 1992-1997 classified, 2dr FWD, 104 inch wheelbase.
STU Request clarification on wing measurement #29640aeroneutralST aero devices and reference areas now include end plates but exclude fasteners protruding over 1/2 inch.
GT3 GT Category Wording #29193wordingunclearGT1, GT2, GT3, GTL, GTX now permit turbocharging/supercharging if listed on spec line.
STU Request for Advanced Aero Rule Wording Clarification. #29124wordingneutralSTU fender flare rules reworded: up to 2" per corner allowed with 1% weight penalty total.
STU Minimum Weight Determination #27695wordingneutralSTL and STU clarify weight adjustment calculation order: engine adjustments first, then chassis adjustments.
STU ST Gurney flap Wicker clarification #29012wordingneutralSTL and STU rear wing rules clarify that wicker is a Gurney flap; no performance change.
GT3 Request to add Mazda 12A Peripheral Port to GT3 rule set #28842cars addedneutralGT3 Mazda 12A Peripheral Port added to rule set, 2300 cc, 2292 lbs.
GT3 TA2 Gurney flap wicker clarification #28874wordingneutralTA2 Gurney flap wording clarified: terminology standardized to 'Gurney flap', height limits and thickness specifications remain 0.50 inch / 0.625 inch or 0.375 inch / 0.0625 inch depending on configuration.
GT3 STO Gurney flap wicker clarification #28883wordingneutralSTO rear wing wording clarified: 'wicker' changed to 'Gurney flap' in maximum chord and mounting height rules.
GT3 GT3 4v SIR size increase. #28931inductionfasterGT3 4v SIR 4-cylinder engines across multiple brands increase fuel induction from 31 to 32.
GT3 Request for Addition to GT3 Approved Turbo List #27576wordingneutralGT3 and STU add Borg-Warner EFR6258 to approved turbocharger list.
STU Request for Alternate Intake Manifold #26514wordingneutralSTU request for alternate intake manifold denied; no rule change issued.
STU Request for Addition to GT3 Approved Turbo List #27576wordingneutralGT3 and STU add Borg-Warner EFR6258 to approved turbocharger list.
STU Request BoP for my Car #29004wordingneutralSTU large displacement turbo engines limited by GCR turbo list; non-turbo trim suggested as more competitive.
STU Sequential Shifters in STU #29031wordingneutralSTU sequential shifters referred to Board of Directors for approval; no change implemented yet.
GT3 Request Nissan KA24E specifications #28808inductionslowerGT3 Nissan KA24E loses permission to use 32mm chokes at 2280 lbs for 2011-2012 only.
STU Rotary Help #27833cars addedneutralSTU Mazda 13B Bridge Port and Street Port engines added with 2550 and 2250 lbs minimum weights respectively.
STU Request to approve Honda S2000 HKS supercharger #27281enginefasterSTU Honda S2000 adds HKS Supercharger kits 12001-AH006 and 12001-AH010 as allowed.
STU Request BoP on the Lotus #27637weight +100 lbsslowerSTU Lotus Elise Cup R and SC models, plus Exige SC, gain 100–200 lbs minimum weight.
STU Turbo Inlet Restrictor On MK5 Volkswagen #27704inductionslowerSTU Volkswagen GTI/GLI MK5 and Jetta Mk4 may install turbo inlet restrictor in OEM turbo inlet housing.
STU Honda K20C1 removal #27732inductionslowerSTU Honda K20C1 Turbo I4 restrictor reduces from 36mm to 35mm.
STU Change GM LNF 2.0 Allowance to LSJ Engine for Viable STL 2.0 #27884engineslowerSTU GM Ecotech LNF now allowed with turbo removed or with LE5 head and intake manifold, meeting STL specs.
STU Alternate Engine for Porsche 944 #28259engineunclearSTU Porsche 944 now permits VW/Audi 1.8L and 2.0L turbo engines as alternates.
GT3 Error Regarding Mazda Engine Listing #28119induction +245 lbsslowerGT3 Mazda MZR L5-VE gets 31mm SIR restrictor, weight up from 1950 to 2195 lbs, direct injection banned.
STU Please Modify the STU Wheel Size Rule for Clarity #27694weightfasterSTU vehicles over 2951 lbs base weight may use 9 inch wide wheels, up from 2950 lbs.
STU Turbo Engine Cars Base Weight #28032wordingneutralSTU turbocharged engines now use base weight instead of minimum weight, with 3% DI increase applied to base weight.
GT3 Windshield Clips #27323wordingneutralGT1, GT2, GT3, GTL, GTX may omit windshield clips if factory glass is bonded per original specifications.
GT3 Request Factory Five Daytona coupe classification #26308cars addedneutralFactory Five Type 65 Coupe R with Ford 302/351 or 5.0/5.2L NA added to GTX-MISC at 2600 lbs.
GT3 Request restrictor size change request #26958inductionslowerGT3 Mazda 13B Bridgeport restrictor reduced from 44mm to 42mm.
GT3 Request to Classify Alfa Romeo 4C #27322cars addedneutralGT3 Alfa Romeo 4C classified with 1742cc engine, 33mm TIR restrictor, 2325 lbs minimum weight.
GT3 Request for Mazda 2.5l MZR/L5-VE #27570induction -245 lbsfasterGT3 Mazda MZR/L5-VE gets unrestricted induction, drops 245 lbs to 1950, limited to GT2 prep.
GT3 GT3 turbo engines add Honda #28033cars addedneutralGT3 Honda K20C1 turbocharged engine added with 33 mm TIR restrictor, 2350 lbs minimum weight.
GT3 GT3 wing end plate #28035aerounclearGT3 wing end plates change from 11.00 by 4.00 inches rectangle to maximum 64 square inches.
GT3 Request to Add SR16VE to GT-3 Spec Lines #27357cars addedneutralGT3 Nissan adds SR16VE engine, 1596cc, 1690 lbs, unrestricted induction.
STU Request for an electronic throttle body #27342wordingneutralSTU cars with manual OEM throttle bodies may convert to OEM electronic throttle body of same inner diameter.
Runoffs 2019 ROFF192019-10-05
1:59.948Kevin Boehm · fastest of 25 · top 5 within 3.5s
2:00.483Kevin Boehm · fastest of 25 · top 5 within 2.5s
143.8Kevin Boehm
1:58.194Michael Lewis · fastest of 17 · top 5 within 2.2s
1:59.045Tony Ave · fastest of 16 · top 5 within 1.7s
149.6Jeff Dernehl
-1.438squal -1.754s
98.8%qual 98.5%
30 earlier rule changes on record, in force before Runoffs 2019 (from 2019)7 cars added · 6 induction · 3 engine · 2 aero · 1 tyres & wheels · 1 weight · 10 wording · GT3 Mazda 12A Bridgeport gains optional 42mm choke at 2010 lbs minimum weight. · STU wing assembly wording corrected: no part higher than roof height. · STU Nissan SR20DET removes -2mm penalty in Table B. · STU alternate intake manifolds now allowed case-by-case instead of prohibited. · STU aftermarket side skirts must meet 3-inch ride height, no openings except jacks or side exhaust, no wider than fascias, not higher than door bottom, no chassis reinforcement. · STU fender flare wording clarified: each fender may be flared up to 2" for tire clearance with 1% weight penalty. · GTX tube frame cars gain fuel injection with 90mm maximum throttle body size. · Ligier JS2 R classified in GTX, no performance parameters specified in filing. · STL and STU ride height measurement clarified: without driver, at rocker panel lowest point, excluding pinch weld. · GT3 Mazda 13B and Renesis engines reclassified with new weight specs ranging 2080–2350 lbs. · GT1 and GT2/GT3/LITE ride height requirements removed from GCR sections 9.1.2.D.5.a.1 and 9.1.2.F.7.b. · STU Mazda 13B Bridge Port may use ELITE ROTARY SHOP FD V2.0 intake manifold instead of stock. · STU Mazda MZR LF/L3/L5 may use Goodwin Part #61-2510 intake manifold with stock or Acura throttle body. · STU suspension rules clarified: alternate components from same manufacturer moved from section E to section D. · STU Honda/Acura B20 classified at 1973 cc, now permits VTEC B16 or B18 cylinder head and intake manifold. · STU flared fenders up to 2" with 1% weight penalty moved from base to Advanced Aero rules. · TCA Honda Civic Si (2017-) must run 37mm TIR maximum as of June 1, 2019. · STU BMW S54B32 OEM reclassified from E46 designation, 3246 cc, 3300 lbs minimum weight. · GT3 13B and Renesis rotaries gain 200 lbs minimum weight; 13B Peripheral Port to 2400, Bridge Port to 2400, Renesis Peripheral Port to 2450, Bridge Port to 2450. · GT3 adds Mitsubishi 4G69 SOHC 2378cc engine, 2195 lbs minimum weight, 31mm SIR. · Honda Civic Si 2017- classified STU at 1500cc, 2800 lbs minimum with OEM engine and bodywork. · STU BMW E46 S54 OEM 3246cc added at 3300 lbs minimum weight, no Super Touring allowances. · STU Mazda 13B and 13B Bridge Port may use RE or REW housings and intake with turbo removed. · STU Honda K24 may use intake part #s 17100-RRB-A00 or 17100-PRB-A10. · STU Mazda 12A Bridge Port engine classified at 2550 lbs minimum weight with specified carburetor induction options. · STU World Challenge car weight calculation method removed; new basis unclear from text provided. · STU AWD cars no longer required to reduce restrictor 1 mm from table. · STU rear wing maximum cord length set to 12 inches, end plates to 72.0 square inches each. · GTX FIA GT3: Audi R8 40mm restrictor 2900 lbs, BMW Z4 70mm 2800 lbs, Ferrari 488 35mm restrictor 3025 lbs classified. · STU Honda K20C1 Turbo I4 1996cc added at 3025 lbs minimum weight with 36mm TIR.showhide
GT3 Requesting Increase in Choke Diameter for Mazda 12A Bridgeport #27043inductionfasterGT3 Mazda 12A Bridgeport gains optional 42mm choke at 2010 lbs minimum weight.
STU Request to correct E&O advanced aerodynamics #27290wordingneutralSTU wing assembly wording corrected: no part higher than roof height.
STU Remove -2mm penalty from SR20DET Nissan #26982enginefasterSTU Nissan SR20DET removes -2mm penalty in Table B.
STU Request clarification for manifold and throttle in STU #27004inductionfasterSTU alternate intake manifolds now allowed case-by-case instead of prohibited.
STU Request to clarify afterrmarket side skirts exhaust exit #26814wordingneutralSTU aftermarket side skirts must meet 3-inch ride height, no openings except jacks or side exhaust, no wider than fascias, not higher than door bottom, no chassis reinforcement.
STU Wheel Flare wording #26872wordingneutralSTU fender flare wording clarified: each fender may be flared up to 2" for tire clearance with 1% weight penalty.
GT3 Request GTX Fuel injection for previous GT-1 tube frame cars #26141inductionfasterGTX tube frame cars gain fuel injection with 90mm maximum throttle body size.
GT3 Request to Classify Ligier JS2 R #26535cars addedneutralLigier JS2 R classified in GTX, no performance parameters specified in filing.
STU Request Ride Height Clarification #26597wordingneutralSTL and STU ride height measurement clarified: without driver, at rocker panel lowest point, excluding pinch weld.
GT3 26076 revised Spec line chart #26528engineunclearGT3 Mazda 13B and Renesis engines reclassified with new weight specs ranging 2080–2350 lbs.
GT3 Request Ride Height Clarification #26600wordingneutralGT1 and GT2/GT3/LITE ride height requirements removed from GCR sections 9.1.2.D.5.a.1 and 9.1.2.F.7.b.
STU Request to Use Japanese Mazda 13b Intake Manifold #25790inductionfasterSTU Mazda 13B Bridge Port may use ELITE ROTARY SHOP FD V2.0 intake manifold instead of stock.
STU Request Alternate Intake for Mazda MZR In a Rear Wheel Drive App. #26352inductionunclearSTU Mazda MZR LF/L3/L5 may use Goodwin Part #61-2510 intake manifold with stock or Acura throttle body.
STU E&O Suspension #26424wordingneutralSTU suspension rules clarified: alternate components from same manufacturer moved from section E to section D.
STU Revisit B20 VTEC #26530enginefasterSTU Honda/Acura B20 classified at 1973 cc, now permits VTEC B16 or B18 cylinder head and intake manifold.
STU Move Flared Fenders to STU Advanced Aero #26564aeroneutralSTU flared fenders up to 2" with 1% weight penalty moved from base to Advanced Aero rules.
STU TCA Civic SI E&O #26606tyres & wheelsslowerTCA Honda Civic Si (2017-) must run 37mm TIR maximum as of June 1, 2019.
STU S54 Spec line #26620wordingneutralSTU BMW S54B32 OEM reclassified from E46 designation, 3246 cc, 3300 lbs minimum weight.
GT3 Request clarification on bridge porting for rotary #26076weightslowerGT3 13B and Renesis rotaries gain 200 lbs minimum weight; 13B Peripheral Port to 2400, Bridge Port to 2400, Renesis Peripheral Port to 2450, Bridge Port to 2450.
STU Request to Class Assignment for 2017 Civic #24287cars addedneutralHonda Civic Si 2017- classified STU at 1500cc, 2800 lbs minimum with OEM engine and bodywork.
STU Request to run E46 3246cc in STU #25126cars addedneutralSTU BMW E46 S54 OEM 3246cc added at 3300 lbs minimum weight, no Super Touring allowances.
STU Engine Classification for Rotary #25564wordingunclearSTU Mazda 13B and 13B Bridge Port may use RE or REW housings and intake with turbo removed.
STU K24/K20 Head Swap Clarification/Amendment #25899wordingneutralSTU Honda K24 may use intake part #s 17100-RRB-A00 or 17100-PRB-A10.
STU Request to Classify 12a Bridge Ported Rotary Engine #25985cars addedneutralSTU Mazda 12A Bridge Port engine classified at 2550 lbs minimum weight with specified carburetor induction options.
STU World Challenge Car Eligibility #26387wordingunclearSTU World Challenge car weight calculation method removed; new basis unclear from text provided.
STU Request a phone call for discussion regarding weight #26398inductionfasterSTU AWD cars no longer required to reduce restrictor 1 mm from table.
STU Advanced Aero E&O #26413aeroneutralSTU rear wing maximum cord length set to 12 inches, end plates to 72.0 square inches each.
GT3 GTX Homologation table update #26034cars addedneutralGTX FIA GT3: Audi R8 40mm restrictor 2900 lbs, BMW Z4 70mm 2800 lbs, Ferrari 488 35mm restrictor 3025 lbs classified.
STU Request to Equalize Direct Injected Turbo Cars #24890cars addedneutralSTU Honda K20C1 Turbo I4 1996cc added at 3025 lbs minimum weight with 36mm TIR.
Best is the class's fastest lap in that event's qualifying or race sessions, with the driver who set it, how many cars set a time that session and how close the top five were; a best from fewer than three cars is greyed. With two or more classes, "vs" is the gap of each class's best to the first class's at the same event. "% of STU" is the class's best as a share of STU's best at the same event (100% is level, less is quicker): weather and track condition move every class together, so this compares across years where the raw times do not. It still breaks when STU's own field changes or one session was wet and another dry. Newest event first. The coloured figure under each value is the change from the previous event that has one (green is quicker, red slower). Whole laps only, so events with different sector layouts still compare. Weather and track condition are not accounted for.