FE vs F6 vs FB vs STU pace at Buttonwillow Raceway Park
Quickest here:STU 1:50.913 Tony Rivera, Super Tour Feb 2026 qualifying
FEF6FBSTUsolid race · dashed qualifying · slower is lower
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Super Tour Feb 2026 CALCL262026-02-21
1:50.913Tony Rivera · fastest of 6 · top 5 within 14.1s-4.488s (-3.89%)
1:52.737Tony Rivera · fastest of 7 · top 5 within 7.7s-0.903s (-0.79%)
135.2Tony Rivera+21.8 mph (+19.3%)
20 rule changes (FE: 3, STU: 17)8 weight · 4 cars added · 3 tyres & wheels · 1 engine · 1 induction · 3 wording · FE adds engine modification restrictions, testing requirements, and drivetrain violation penalties with competition suspension. · STU Mazda MZR (LF, L3, L5) Turbo added; Goodwin intake removed, Jack Spania Racing 70 mm intake and Fab9 Tuning bottom-mount turbo kit approved. · STU 36mm restrictor revised to 2830 cc, 37mm to 2980 cc. · STU removes 275 tire option and 2% weight adder for cars over 3150 lbs; maximum section width now 245. · STU Honda K20 and K24 engines lose 2% weight penalty; minimum weight now per chart only. · STU Honda K24 engine swap weight increases by 2 percent, effective November 1, 2025. · FE and FE2 Enterprise bubble tail part WM138014 now allowed; FE2 must use this configuration only. · FE2 minimum weight stays 1270 lbs; intake manifold part number changes to WM301061; ECU to G992012; mandatory spec parts expanded; bubble tail WM138014 now FE only; SADEV transmission no modifications allowed; brake rotor part numbers to W… · STU Lotus Elise SC and Exige SC weight reduced from 2450 to 2250 lbs. · STU-TCR gains GT3 TCR spec lines; 275 tyre option now costs 150 lb adder, up from 100 lb. · Lotus Evora GT4 minimum weight drops to 2700 lbs; Elise Cup R to 2250 lbs; Elise SC and Exige SC to 2450–2550 lbs. · STU 2.8–3.2L N/A engines now permit 245 max tyre width; over 3150 lbs cars may run 275 with 2% weight penalty. · STU Mazda MZR intake manifold now allows Goodwin 61-2510 or Gato Performance 31972. · STU Honda JDM H23a added, 2259 cc, minimum weight per chart, must meet ST engine regulations. · STU wheels capped at 18 inches diameter; under 2,850 lbs max 8 inches wide, over 2,850 lbs max 9 inches wide. · STU-GT3U minimum weight reduced from plus 250 to plus 225 pounds; wheel and tyre options clarified with weight adjustments. · STU BMW N54/N55 3.0 classified at chart plus 3% minimum weight; N54 twin turbo not allowed. · STU Mini Cooper S SC pulley diameter reduced to 2.185 inches. · STU Honda K20C1 Turbo I4 exempted from 3% direct injection weight adder. · STU GT3U minimum weight increases 150 pounds to 250 pounds.showhide
FE FE & FE2 Rule Updates #39484wordingwordingFE adds engine modification restrictions, testing requirements, and drivetrain violation penalties with competition suspension.
STU Request for Permission on Aftermarket Turbo Kit and Intake #39529cars addedaddedSTU Mazda MZR (LF, L3, L5) Turbo added; Goodwin intake removed, Jack Spania Racing 70 mm intake and Fab9 Tuning bottom-mount turbo kit approved.
STU Turbo Inlet Restrictor Table #38961wordingwordingSTU 36mm restrictor revised to 2830 cc, 37mm to 2980 cc.
STU 275 Tire Rule #38983tyres & wheelsslower · tyres & wheelsSTU removes 275 tire option and 2% weight adder for cars over 3150 lbs; maximum section width now 245.
STU STU Honda Engine weight penalty #39375weightfaster · weightSTU Honda K20 and K24 engines lose 2% weight penalty; minimum weight now per chart only.
STU Non-Homologated Engine Swaps - Specifically K24A2 w/ Honda CRZ #38746weightslower · weightSTU Honda K24 engine swap weight increases by 2 percent, effective November 1, 2025.
FE FE & FE2 Bubble Tail #38978cars addedaddedFE and FE2 Enterprise bubble tail part WM138014 now allowed; FE2 must use this configuration only.
FE FE & FE2 Rule Updates #38901wordingwordingFE2 minimum weight stays 1270 lbs; intake manifold part number changes to WM301061; ECU to G992012; mandatory spec parts expanded; bubble tail WM138014 now FE only; SADEV transmission no modifications allowed; brake rotor part numbers to W…
STU Lotus Weight Reduction E&O #38919weightfaster · weightSTU Lotus Elise SC and Exige SC weight reduced from 2450 to 2250 lbs.
STU STU-TCR Adjustments #38723weightslower · weightSTU-TCR gains GT3 TCR spec lines; 275 tyre option now costs 150 lb adder, up from 100 lb.
STU Lotus Weight Reduction #38772weight -50 lbsfaster · weightLotus Evora GT4 minimum weight drops to 2700 lbs; Elise Cup R to 2250 lbs; Elise SC and Exige SC to 2450–2550 lbs.
STU 2.8-3.2L N/A Engine Allowances #38007tyres & wheelsfaster · tyres & wheelsSTU 2.8–3.2L N/A engines now permit 245 max tyre width; over 3150 lbs cars may run 275 with 2% weight penalty.
STU 2006-2015 Mazda Miata Intake Manifold #38422engineadded · engineSTU Mazda MZR intake manifold now allows Goodwin 61-2510 or Gato Performance 31972.
STU Requesting Approval of the JDM Honda h23a #38489cars addedaddedSTU Honda JDM H23a added, 2259 cc, minimum weight per chart, must meet ST engine regulations.
STU Wheel Size Inconsistency #38018tyres & wheelstyres & wheelsSTU wheels capped at 18 inches diameter; under 2,850 lbs max 8 inches wide, over 2,850 lbs max 9 inches wide.
STU Table C: STU-GT3U Clarification #38268weightfaster · weightSTU-GT3U minimum weight reduced from plus 250 to plus 225 pounds; wheel and tyre options clarified with weight adjustments.
STU BMW N54/N55 Engine Allowance Follow Up #37447cars addedaddedSTU BMW N54/N55 3.0 classified at chart plus 3% minimum weight; N54 twin turbo not allowed.
STU STU Mini Cooper pulley size clarification re: letter #36980 #37717inductionfaster · inductionSTU Mini Cooper S SC pulley diameter reduced to 2.185 inches.
STU Question About a Weight Modifier #37782weightfaster · weightSTU Honda K20C1 Turbo I4 exempted from 3% direct injection weight adder.
STU Increase Minimum Weight #37919weight +100 lbsslower · weightSTU GT3U minimum weight increases 150 pounds to 250 pounds.
Super Tour Feb 2025 CALCL252025-02-22
1:55.401Wilson Powell · fastest of 4 · top 4 within 8.7s
1:53.640Rylan Hazelton · fastest of 5 · top 5 within 8.0s
113.3Rylan Hazelton
95 rule changes (FE: 26, STU: 69)12 engine · 11 weight · 10 cars added · 9 aero · 5 tyres & wheels · 4 suspension & brakes · 1 induction · 36 wording · 7 other · STU Audi 1.8T Wagon removed; Porsche 944 1800cc weight to Chart, turbo inlet restrictor deleted. · STU-GT3 reclassified as STU-GT3U, effective 1 January 2026. · STU GT3 TCR may run 275-wide DOT tires with 100 lb weight penalty; A compound prohibited at 275. · FE must use SCCA Part # WM803010 Brake Line to Control Arm covers if used, as delivered, fastened with zip ties or tape only. · STL STU Mazda Miata alternate front hubs Mazda Motorsports Development Part #0000-04-5HUB-S1 approved. · STU BMW N54/N55 turbo inlet restrictors now required per GCR definition; twin turbo conversion to single turbo clarified. · STU Mini Cooper S SC: 1900 stock pulley spec to 2.565 diameter; 2100 now permits 2.285 diameter pulley. · FE and SRF protest fee rules redirected to GCR section 8.3.1.D for fees and procedure. · FE Hoosier contingency decal requirement reduced from five decals in specific locations to three decals on sides and front. · FE requires five Hoosier decals: one small on nose or front shock cover, one 12" on each front wing plate, one 12" on each lower floor panel before rear wheels. · STU RWD turbo cars no longer required to reduce inlet restrictor by 1 mm from table minimum. · STU Mini Cooper S SC gains alternate LEAP OMICRON hood scoop part LEP-OMICRON3 as permitted option. · STU BMW S54 B32 OEM dry sump oiling system now permitted. · STL and STU now permit electric power steering pumps, OEM electric-assisted steering, or column-mounted electric steering assist systems. · FE rain light now must meet FIA Standard 8874-2019, Technical List No. 76, effective 1/1/2024. · FE allows racer's tape for crash repair, panel security, and heat exchanger opening control; seam taping banned. · STU adds 2022 Toyota GR Cup and GR86 Cup, both 2387cc, 2700 lbs, 18-inch wheels, 245/620R18 slicks. · FE SADEV transmission rule removes note that all ratios under review and could be updated prior to sealing. · STU Mazda BP5A now classified at 1839 cc displacement, 2510 lbs minimum weight, alternate intake manifold permitted. · STU minimum weights adjusted: 2450 cc to 2595 lbs, 2600 cc to 2710 lbs. · FE drivers may now adjust brake bias manually during the race. · FE front and rear wing specifications clarified: adjustment ranges, shimming, Gurney flap sizes, mounting hardware, and measurement references refined. · FE engine heat shield and insulation between block and exhaust now permitted to protect fuel cell, filter, rail, lines. · STU Mazda 13B Turbo added as Chart Limited displacement, streetport only, alternative turbos only. · STU OEM louver vents no longer count against vent allowance or 200 square inch limit. · STU non-4-valve engines gain 9% base engine weight reduction allowance; 2400cc minimum weight drops 1 lb to 2595. · STU normally-aspirated engines 2976cc–3200cc with single throttle body lose 10% base engine weight reduction allowance. · ST removes redundant language about engine balance shaft removal and alternate pulley installation. · FE tires must be run as delivered in sets of 4. · FE master cylinders clarified: Girling front .700" piston WM802005, rear .750" piston WM802006. · STU cars that qualified for 9 inch wheels in 2021 may continue running them through 2022 only. · STU splitter definition clarified: must attach to lowest point of front, have no vertical deviations. · STU BMW E36 M3 (95-99) S52B32 minimum weight cut to 3110 lbs from 3200, displacement to 3152 cc. · STU BMW S50B32 Euro maximum displacement 3201 cc, minimum weight 3300 lbs, permits 0.040 overbore and 0.5 compression increase. · ST engine swap origin rule narrowed: North America changed to United States only for case-by-case approval. · STU Honda CRX 84-91 and Civic Del Sol 93-97 both ineligible for front-wheel-drive weight reductions. · STU wheel width rule clarified: under 2950 lbs uses max 8.0 inches, 2950 lbs and over uses max 9.0 inches. · STU single-throttle body cars get lower minimum weights: 2450cc to 2596 lbs, 2500cc to 2635 lbs, 2550cc to 2675 lbs. · STU single throttle body weight reduction removed; minimum weights revised down to 2990 lbs at 3000cc from 3300 lbs. · STU Audi A4 1.8T minimum weight fixed to 3050 lbs, K04 turbo removed, VF30 with 35mm restrictor required; Porsche 944 1800 weight fixed to 3050 lbs, VW/Audi 1.8L engine removed, 35mm inlet restrictor required. · STL and STU Improved Touring vehicles must now conform to section 9.1.4 Tires & Wheels. · STU engines may delete balance shafts and plug openings; alternate pulleys or gears allowed only for timing belt or chain operation. · STU hood vents now allow louvers within 200 square inches. · STU adds Honda K23 with 2354 cc displacement and chart minimum weight, K24 block allowed with K23 internals and head. · STU Honda K23 relaxes internal engine requirement, now needs only K23 crankshaft. · STL/STU intake manifold and cylinder head porting clarified as free; intake and exhaust porting wording removed. · FE removes qualifying tire marking requirements and rain tire set rules; renumbers tire warmer prohibition. · FE radiator screens may not protrude more than ¼ inch in front of the outside vertical plane of the sidepods. · STU fender flare wording clarified: flare of exterior contour may not change wheel opening size, location or shape from side view. · STU Mazda 12A Bridgeport weight reduced from 2550 lbs to 2350 lbs. · FE radiator screens now allowed, maximum ¼ inch from sidepod front vertical plane. · STU fender flare rules clarified: maximum 2 inches total, must cover tire contact patch from above, cannot alter body configuration or wheel opening geometry. · STU Honda S2000 now allows F20/F22 K24 crankshaft with chart weight for achieved displacement. · ST oil coolers and filters now explicitly listed as addable or substitutable parts in vents and breathers section. · ST 90-05 Mazda Miata allowed alternate front wheel hub Mazda Motorsports Development Part #0000-04-5HUB-S1. · ST cars may now relocate ABS actuation hardware and wiring anywhere in the engine compartment. · STU Porsche PDK automatic transmission limited to 8 forward speeds; sequential DCT systems require 3.5% minimum weight increase. · STU Mazda 13B Street Port 2400 removes choke location rule, allows auto-type 2bbl with any dual-Y manifold. · STU driveshaft and half-shafts now explicitly permitted in steel or aluminum, removing OEM material requirement. · STU Mazda 13B Spec and Bridge Port removed; Street Port added at 2400 lbs minimum weight. · FE front springs change to 800 lbs Hypercoil WM203013 Silver; rear to 900 lbs Hypercoil WM203014 Silver. · ST aero devices and reference areas must include end plates, exclude fasteners under 1/2" protrusion. · FE Gurney flaps clarified: front wing secondary only at 0.500" ±0.030", rear wing at 0.250" ±0.030". · STU fender flare rule reworded: now per-corner up to 2" total, 1% weight penalty applies to entire modification. · 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. · STU request for alternate intake manifold denied; no change to rules. · GT3 and STU add Borg-Warner EFR6258 turbocharger to approved turbo lists. · STU large displacement turbo engines limited by GCR turbo list; no BoP change granted. · STU sequential shifters referred to Board of Directors for approval; no rule change effective. · FE Gurney flap wicker bill clarified: permitted on front wing secondary elements only, not main plane. · STU Mazda 13B Bridge Port and Street Port added with 2550 lbs and 2250 lbs minimum weight respectively. · FE2 and FE spring part numbers WM203013 front and WM203014 rear required date moved to November 1, 2020. · STU Honda S2000 gains HKS Supercharger kits 12001-AH006 and 12001-AH010 as allowed options. · STU Lotus Elise Cup R and SC Exige SC gain 100 lbs minimum weight to 2300, 2500. · STU Volkswagen GTI/GLI MK5 and Jetta Mk4 may now install turbo inlet restrictor in OEM housing, per TIR spec. · STU Honda K20C1 Turbo I4 restrictor reduces from 36mm to 35mm. · STU GM Ecotech LNF now permitted without turbo, 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 to original. · STU vehicles over 2951 lbs base weight may use 9 inch wide wheels, changed from 2950 lbs. · STU turbocharged engines now use base weight instead of minimum weight; DFI cars add 3% to base weight. · FE2 Mazda 2.0L MZR engine now permitted in all SCCA events at 1250 lbs minimum; FE 2.3L becomes Regional Only through 2019 Runoffs. · FE minimum weight rises to 1270 lbs; FE2 minimum weight rises to 1270 lbs; new spring options added; tire warmers prohibited. · STU allows OEM electronic throttle bodies, manual conversion, cam changes, and manual-to-electronic conversion with same inner diameter. · FE Hoosier wet rear tire width increases from 7.5 to 8.0 inches, part number 44196 W3. · STU wing assembly wording corrected: no part may be higher than roof height. · FE removes American Racer tires, mandates Hoosier dry tires 22.0 X 8.0-13 and 22.0 X 10.0-13, wet tires 22.0 X 7.5-13 and 22.0 X 9.0-13. · STU Nissan SR20DET removes -2mm penalty from Table B. · STU allows alternate intake manifolds on case-by-case basis; stock throttle device and manifold otherwise required. · FE anti-roll bar links may be removed one per end for safety, but bars must stay connected. · FE and FE2 Enterprise bubble tail P/N WM138014 newly allowed for both classes. · STU aftermarket side skirts now allowed if they meet 3-inch ride height, lack ducts except jacks or exhaust, don't exceed fascia width, stay below door bottom, and don't reinforce chassis. · STU wheel flare wording clarified: each fender may be flared to 2" with 1% weight penalty, maintaining OEM profile. · STL and STU ride height measurement clarified: lowest rocker panel point without driver, excluding pinch weld.showhide
STU Audi 1.8t Wagon STU Table B #36685cars addedremoved · cars addedSTU Audi 1.8T Wagon removed; Porsche 944 1800cc weight to Chart, turbo inlet restrictor deleted.
STU Merger GT3 to STU #37486wordingunclearSTU-GT3 reclassified as STU-GT3U, effective 1 January 2026.
STU GT3 TCR Tire allowance #37494tyres & wheelsadded · tyres & wheelsSTU GT3 TCR may run 275-wide DOT tires with 100 lb weight penalty; A compound prohibited at 275.
FE Brake Line to A-Arm Covers #37110otheraddedFE must use SCCA Part # WM803010 Brake Line to Control Arm covers if used, as delivered, fastened with zip ties or tape only.
STU 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.
STU BMW N54/N55 Engine Allowance #37146wordingwordingSTU BMW N54/N55 turbo inlet restrictors now required per GCR definition; twin turbo conversion to single turbo clarified.
STU R53 15% Pulley Request #36980enginefaster · engineSTU Mini Cooper S SC: 1900 stock pulley spec to 2.565 diameter; 2100 now permits 2.285 diameter pulley.
FE Protest Fee Clarification #36540wordingwordingFE and SRF protest fee rules redirected to GCR section 8.3.1.D for fees and procedure.
FE Update on Letter 36620 with new Hoosier Contingency Decal Info #36625wordingwordingFE Hoosier contingency decal requirement reduced from five decals in specific locations to three decals on sides and front.
FE Hoosier Tire Decal Placement #36435wordingaddedFE requires five Hoosier decals: one small on nose or front shock cover, one 12" on each front wing plate, one 12" on each lower floor panel before rear wheels.
STU RWD Turbo Disadvantage #36255inductionfaster · inductionSTU RWD turbo cars no longer required to reduce inlet restrictor by 1 mm from table minimum.
STU Letter #35397 addendum #35453aeroadded · aeroSTU Mini Cooper S SC gains alternate LEAP OMICRON hood scoop part LEP-OMICRON3 as permitted option.
STU S54 Drysump #35464otheraddedSTU BMW S54 B32 OEM dry sump oiling system now permitted.
STU ST Electric-Assisted Steering Systems #35066aeroadded · aeroSTL and STU now permit electric power steering pumps, OEM electric-assisted steering, or column-mounted electric steering assist systems.
FE Update FE Rain Light Rule #34707wordingwordingFE rain light now must meet FIA Standard 8874-2019, Technical List No. 76, effective 1/1/2024.
FE FE/FE2 rule update #35269wordingwordingFE allows racer's tape for crash repair, panel security, and heat exchanger opening control; seam taping banned.
STU 2022 Toyota GR Cup for STU #34449cars addedaddedSTU adds 2022 Toyota GR Cup and GR86 Cup, both 2387cc, 2700 lbs, 18-inch wheels, 245/620R18 slicks.
FE Update FE SADEV Transmission Rule #33883wordingwordingFE SADEV transmission rule removes note that all ratios under review and could be updated prior to sealing.
STU Alternate OEM Miata Intake Manifold #33827engineadded · engineSTU Mazda BP5A now classified at 1839 cc displacement, 2510 lbs minimum weight, alternate intake manifold permitted.
STU E&O STU NA Weight Chart. #33737weightfaster · weightSTU minimum weights adjusted: 2450 cc to 2595 lbs, 2600 cc to 2710 lbs.
FE Brake bias adjuster clarification #33084suspension & brakesadded · suspension & brakesFE drivers may now adjust brake bias manually during the race.
FE FE Front and Rear Wing Update & Clarification #33089wordingwordingFE front and rear wing specifications clarified: adjustment ranges, shimming, Gurney flap sizes, mounting hardware, and measurement references refined.
FE Engine Heat Shield & Insulation #33019otheraddedFE engine heat shield and insulation between block and exhaust now permitted to protect fuel cell, filter, rail, lines.
STU Request Mazda 13 B turbo #32668cars addedaddedSTU Mazda 13B Turbo added as Chart Limited displacement, streetport only, alternative turbos only.
STU Hood Vents and Intercooler Scoops #32733aeroadded · aeroSTU OEM louver vents no longer count against vent allowance or 200 square inch limit.
STU Non 4 valve weight reduction removed #32808weightfaster · weightSTU non-4-valve engines gain 9% base engine weight reduction allowance; 2400cc minimum weight drops 1 lb to 2595.
STU Error in new minimum weight table when combined with other text #32711engineslower · engineSTU normally-aspirated engines 2976cc–3200cc with single throttle body lose 10% base engine weight reduction allowance.
STU Redundant Language in May GCR #32713wordingwordingST removes redundant language about engine balance shaft removal and alternate pulley installation.
FE Update FE/FE2 Tire Rule #32613wordingwordingFE tires must be run as delivered in sets of 4.
FE Master cylinder clarification #32669wordingwordingFE master cylinders clarified: Girling front .700" piston WM802005, rear .750" piston WM802006.
STU Opposed to the Proposed STU Weight Chart #32381tyres & wheelsadded · tyres & wheelsSTU cars that qualified for 9 inch wheels in 2021 may continue running them through 2022 only.
STU Clarification request for GCR 9.1.4.D.3.a Splitter Definition #32414wordingwordingSTU splitter definition clarified: must attach to lowest point of front, have no vertical deviations.
STU Request Adjustment to Min Weight for STU BMW E36 M3 (95-99) #31535weight -90 lbsfaster · weightSTU BMW E36 M3 (95-99) S52B32 minimum weight cut to 3110 lbs from 3200, displacement to 3152 cc.
STU BMW E36 M3 Canadian (North American) S50B32 engine #31866engineadded · engineSTU BMW S50B32 Euro maximum displacement 3201 cc, minimum weight 3300 lbs, permits 0.040 overbore and 0.5 compression increase.
STU Engine Swap Origin Country #32209wordingwordingST engine swap origin rule narrowed: North America changed to United States only for case-by-case approval.
STU CRX/Civic Del Sol #32214weightslower · weightSTU Honda CRX 84-91 and Civic Del Sol 93-97 both ineligible for front-wheel-drive weight reductions.
STU Error correction #32383wordingwordingSTU wheel width rule clarified: under 2950 lbs uses max 8.0 inches, 2950 lbs and over uses max 9.0 inches.
STU Single TB Weight Modifiers Add to Chart #32393weightfaster · weightSTU single-throttle body cars get lower minimum weights: 2450cc to 2596 lbs, 2500cc to 2635 lbs, 2550cc to 2675 lbs.
STU Single TB Weight Modifiers #31449weightfaster · weightSTU single throttle body weight reduction removed; minimum weights revised down to 2990 lbs at 3000cc from 3300 lbs.
STU Request to Remove A4 1.8t from STU Spec Line Tables #31465weightslower · weightSTU Audi A4 1.8T minimum weight fixed to 3050 lbs, K04 turbo removed, VF30 with 35mm restrictor required; Porsche 944 1800 weight fixed to 3050 lbs, VW/Audi 1.8L engine removed, 35mm inlet restrictor required.
STU Improved Touring Tires #32063tyres & wheelstyres & wheelsSTL and STU Improved Touring vehicles must now conform to section 9.1.4 Tires & Wheels.
STU Request Allowance for Balance Shaft Delete in STU #31434enginefaster · engineSTU engines may delete balance shafts and plug openings; alternate pulleys or gears allowed only for timing belt or chain operation.
STU Request Louvers in hood vents #31916aeroadded · aeroSTU hood vents now allow louvers within 200 square inches.
STU Request to Add Honda K23 Spec Line #30682cars addedaddedSTU adds Honda K23 with 2354 cc displacement and chart minimum weight, K24 block allowed with K23 internals and head.
STU RE: Aug FT letter 30682 #31060enginefaster · engineSTU Honda K23 relaxes internal engine requirement, now needs only K23 crankshaft.
STU Throttling Device Clarification #31323wordingwordingSTL/STU intake manifold and cylinder head porting clarified as free; intake and exhaust porting wording removed.
FE FE Tire Rule Changes #30754wordingwordingFE removes qualifying tire marking requirements and rain tire set rules; renumbers tire warmer prohibition.
FE Radiator Screens Clarification #30792wordingwordingFE radiator screens may not protrude more than ¼ inch in front of the outside vertical plane of the sidepods.
STU STU Fender flares #30696wordingwordingSTU fender flare wording clarified: flare of exterior contour may not change wheel opening size, location or shape from side view.
STU Request weight reduction for 12A bridgeport motor in Miata #30751weight -200 lbsfaster · weightSTU Mazda 12A Bridgeport weight reduced from 2550 lbs to 2350 lbs.
FE FE Radiator Screens #30575aeroadded · aeroFE radiator screens now allowed, maximum ¼ inch from sidepod front vertical plane.
STU Request for Fender Flare Clarification #30375wordingwordingSTU fender flare rules clarified: maximum 2 inches total, must cover tire contact patch from above, cannot alter body configuration or wheel opening geometry.
STU Provision for Interchangeable Engine Components Already Allowed #30342engineadded · engineSTU Honda S2000 now allows F20/F22 K24 crankshaft with chart weight for achieved displacement.
STU 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.
STU Super Touring Alternate Miata Hubs #30345cars addedaddedST 90-05 Mazda Miata allowed alternate front wheel hub Mazda Motorsports Development Part #0000-04-5HUB-S1.
STU Brake Component Relocation #29990suspension & brakessuspension & brakesST cars may now relocate ABS actuation hardware and wiring anywhere in the engine compartment.
STU Porsche PDK #30081wordingwordingSTU Porsche PDK automatic transmission limited to 8 forward speeds; sequential DCT systems require 3.5% minimum weight increase.
STU Reference Letter #29333 Proposed STU 13B Spec Line Changes #30086wordingwordingSTU Mazda 13B Street Port 2400 removes choke location rule, allows auto-type 2bbl with any dual-Y manifold.
STU Drive Shaft Request #30087otherotherSTU driveshaft and half-shafts now explicitly permitted in steel or aluminum, removing OEM material requirement.
STU 13B Rules Adjustment #29333cars addedremoved · cars addedSTU Mazda 13B Spec and Bridge Port removed; Street Port added at 2400 lbs minimum weight.
FE FE / FE2 Spring Updates #29689suspension & brakessuspension & brakesFE front springs change to 800 lbs Hypercoil WM203013 Silver; rear to 900 lbs Hypercoil WM203014 Silver.
STU Request clarification on wing measurement #29640aeroaeroST aero devices and reference areas must include end plates, exclude fasteners under 1/2" protrusion.
FE FE Gurney Flap Spec Update #29445aeroaeroFE Gurney flaps clarified: front wing secondary only at 0.500" ±0.030", rear wing at 0.250" ±0.030".
STU Request for Advanced Aero Rule Wording Clarification. #29124wordingwordingSTU fender flare rule reworded: now per-corner up to 2" total, 1% weight penalty applies to entire modification.
STU Minimum Weight Determination #27695wordingwordingSTL and STU clarify weight adjustment calculation order: engine adjustments first, then chassis percentage additions, subtractions, and fixed pounds.
STU ST Gurney flap Wicker clarification #29012wordingwordingSTL STU rear wing Gurney flap terminology clarified from wicker to Gurney flap in mounting and chord rules.
STU Request for Alternate Intake Manifold #26514wordingunclearSTU request for alternate intake manifold denied; no change to rules.
STU Request for Addition to GT3 Approved Turbo List #27576cars addedaddedGT3 and STU add Borg-Warner EFR6258 turbocharger to approved turbo lists.
STU Request BoP for my Car #29004wordingunclearSTU large displacement turbo engines limited by GCR turbo list; no BoP change granted.
STU Sequential Shifters in STU #29031wordingunclearSTU sequential shifters referred to Board of Directors for approval; no rule change effective.
FE FE Gurney flap wicker clarification #28885wordingwordingFE Gurney flap wicker bill clarified: permitted on front wing secondary elements only, not main plane.
STU Rotary Help #27833cars addedaddedSTU Mazda 13B Bridge Port and Street Port added with 2550 lbs and 2250 lbs minimum weight respectively.
FE FE spring rule update changed to November 1, 2020 #28814wordingwordingFE2 and FE spring part numbers WM203013 front and WM203014 rear required date moved to November 1, 2020.
STU Request to approve Honda S2000 HKS supercharger #27281otheraddedSTU Honda S2000 gains HKS Supercharger kits 12001-AH006 and 12001-AH010 as allowed options.
STU Request BoP on the Lotus #27637weight +100 lbsslower · weightSTU Lotus Elise Cup R and SC Exige SC gain 100 lbs minimum weight to 2300, 2500.
STU Turbo Inlet Restrictor On MK5 Volkswagen #27704otherslowerSTU Volkswagen GTI/GLI MK5 and Jetta Mk4 may now install turbo inlet restrictor in OEM housing, per TIR spec.
STU Honda K20C1 removal #27732engineslower · engineSTU 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 #27884engineadded · engineSTU GM Ecotech LNF now permitted without turbo, with LE5 head and intake manifold, meeting STL specs.
STU Alternate Engine for Porsche 944 #28259engineadded · engineSTU Porsche 944 now permits VW/Audi 1.8L and 2.0L turbo engines as alternates to original.
STU Please Modify the STU Wheel Size Rule for Clarity #27694weightfaster · weightSTU vehicles over 2951 lbs base weight may use 9 inch wide wheels, changed from 2950 lbs.
STU Turbo Engine Cars Base Weight #28032wordingwordingSTU turbocharged engines now use base weight instead of minimum weight; DFI cars add 3% to base weight.
FE Request for FE / FE2 preparation rules update #27722cars addedaddedFE2 Mazda 2.0L MZR engine now permitted in all SCCA events at 1250 lbs minimum; FE 2.3L becomes Regional Only through 2019 Runoffs.
FE FE / FE2 Update Rules #27624weightslower · weightFE minimum weight rises to 1270 lbs; FE2 minimum weight rises to 1270 lbs; new spring options added; tire warmers prohibited.
STU Request for an electronic throttle body #27342engineadded · engineSTU allows OEM electronic throttle bodies, manual conversion, cam changes, and manual-to-electronic conversion with same inner diameter.
FE FE Wet Tire E&O #27365tyres & wheelstyres & wheelsFE Hoosier wet rear tire width increases from 7.5 to 8.0 inches, part number 44196 W3.
STU Request to correct E&O advanced aerodynamics #27290wordingwordingSTU wing assembly wording corrected: no part may be higher than roof height.
FE FE Tire Update #27029tyres & wheelstyres & wheelsFE removes American Racer tires, mandates Hoosier dry tires 22.0 X 8.0-13 and 22.0 X 10.0-13, wet tires 22.0 X 7.5-13 and 22.0 X 9.0-13.
STU Remove -2mm penalty from SR20DET Nissan #26982enginefaster · engineSTU Nissan SR20DET removes -2mm penalty from Table B.
STU 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.
FE FE Anti-Roll Bar Clarification #26912suspension & brakessuspension & brakesFE anti-roll bar links may be removed one per end for safety, but bars must stay connected.
FE FE / FE2 Updated Bubble Tail Rule #26913aeroadded · aeroFE and FE2 Enterprise bubble tail P/N WM138014 newly allowed for both classes.
STU Request to clarify afterrmarket side skirts exhaust exit #26814aeroadded · aeroSTU aftermarket side skirts now allowed if they meet 3-inch ride height, lack ducts except jacks or exhaust, don't exceed fascia width, stay below door bottom, and don't reinforce chassis.
STU Wheel Flare wording #26872wordingwordingSTU wheel flare wording clarified: each fender may be flared to 2" with 1% weight penalty, maintaining OEM profile.
STU Request Ride Height Clarification #26597wordingwordingSTL and STU ride height measurement clarified: lowest rocker panel point without driver, excluding pinch weld.
Super Tour Apr 2019 ST19APR262019-04-26
17 earlier rule changes on record, in force before Super Tour Apr 2019 (from 2019)5 cars added · 3 engine · 3 induction · 2 aero · 1 tyres & wheels · 2 wording · 1 other · STU Mazda 13B Bridge Port now permits ELITE ROTARY SHOP FD V2.0 intake manifold; stock throttle body requirement removed. · STU Mazda MZR gains alternate Goodwin intake manifold option with stock or Acura throttle body. · STU alternate suspension components rule moved from section E to section D. · STU Honda/Acura B20 now permits B16 or B18 VTEC cylinder head and matching intake manifold. · STU flared fenders up to 2" with 1% weight penalty moved from base to Advanced Aero. · STU Honda Civic Si TCA 2017- requires 37mm TIR throttle as of June 1, 2019. · STU BMW S54B32 OEM classified separately from E46, displacement 3246 cc, minimum weight 3300 lbs, OEM engine mandatory. · FE Hoosier rain tyre part numbers updated: front 44195 W3, rear 44217 W3. · Honda Civic Si 2017- added to STU with 1500cc displacement, 2800 lbs minimum weight, OEM engine and bodywork, specific HPD parts allowed. · STU BMW E46 S54 OEM 3246cc added at 3300 lbs minimum; no Super Touring allowances, OEM intake and cams, 1mm overbore, compression +0.5 permitted. · STU Mazda 13B and 13B Bridge Port may use 13B RE or REW housings and intake with turbo removed. · STU Honda K24 may use intake part numbers 17100-RRB-A00 or 17100-PRB-A10. · STU Mazda 12A Bridge Port added, minimum weight 2550 lbs, Nikki or Auto-type carburettor with specified modifications. · STU World Challenge car weight rule deleted; no replacement specified. · STU AWD/RWD cars no longer must reduce restrictor 1 mm from table. · STU rear wing maximum 12" cord, 72 sq in end plates each, roof height max, body width limit. · STU adds Honda K20C1 Turbo I4, 1996 cc, 3025 lbs minimum weight, 36mm TIR required.showhide
STU Request to Use Japanese Mazda 13b Intake Manifold #25790engineadded · engineSTU Mazda 13B Bridge Port now permits ELITE ROTARY SHOP FD V2.0 intake manifold; stock throttle body requirement removed.
STU Request Alternate Intake for Mazda MZR In a Rear Wheel Drive App. #26352inductionadded · inductionSTU Mazda MZR gains alternate Goodwin intake manifold option with stock or Acura throttle body.
STU E&O Suspension #26424wordingwordingSTU alternate suspension components rule moved from section E to section D.
STU Revisit B20 VTEC #26530engineadded · engineSTU Honda/Acura B20 now permits B16 or B18 VTEC cylinder head and matching intake manifold.
STU Move Flared Fenders to STU Advanced Aero #26564aeroaeroSTU flared fenders up to 2" with 1% weight penalty moved from base to Advanced Aero.
STU TCA Civic SI E&O #26606inductionslower · inductionSTU Honda Civic Si TCA 2017- requires 37mm TIR throttle as of June 1, 2019.
STU S54 Spec line #26620cars addedcars addedSTU BMW S54B32 OEM classified separately from E46, displacement 3246 cc, minimum weight 3300 lbs, OEM engine mandatory.
FE Request to Update Hoosier Rain Tire Part Number for the FE cars #26235tyres & wheelstyres & wheelsFE Hoosier rain tyre part numbers updated: front 44195 W3, rear 44217 W3.
STU Request to Class Assignment for 2017 Civic #24287cars addedaddedHonda Civic Si 2017- added to STU with 1500cc displacement, 2800 lbs minimum weight, OEM engine and bodywork, specific HPD parts allowed.
STU Request to run E46 3246cc in STU #25126cars addedaddedSTU BMW E46 S54 OEM 3246cc added at 3300 lbs minimum; no Super Touring allowances, OEM intake and cams, 1mm overbore, compression +0.5 permitted.
STU Engine Classification for Rotary #25564engineadded · engineSTU Mazda 13B and 13B Bridge Port may use 13B RE or REW housings and intake with turbo removed.
STU K24/K20 Head Swap Clarification/Amendment #25899otheraddedSTU Honda K24 may use intake part numbers 17100-RRB-A00 or 17100-PRB-A10.
STU Request to Classify 12a Bridge Ported Rotary Engine #25985cars addedaddedSTU Mazda 12A Bridge Port added, minimum weight 2550 lbs, Nikki or Auto-type carburettor with specified modifications.
STU World Challenge Car Eligibility #26387wordingunclearSTU World Challenge car weight rule deleted; no replacement specified.
STU Request a phone call for discussion regarding weight #26398inductionfaster · inductionSTU AWD/RWD cars no longer must reduce restrictor 1 mm from table.
STU Advanced Aero E&O #26413aeroadded · aeroSTU rear wing maximum 12" cord, 72 sq in end plates each, roof height max, body width limit.
STU Request to Equalize Direct Injected Turbo Cars #24890cars addedaddedSTU adds Honda K20C1 Turbo I4, 1996 cc, 3025 lbs minimum weight, 36mm TIR required.
About this data
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 FE" is the class's best as a share of FE'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 FE'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.