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BoP Lab / Michelin Raceway Road Atlanta

AS vs SRF vs STU vs FP pace at Michelin Raceway Road Atlanta

Class · click a class to switch, + to compare alongside (up to 4: remove one to add another)
Reference class · the others' laps as a share of this one's at the same event, so years compare despite weather; + a class above to measure against it

Quickest here: AS 1:34.231 Tom Ellis, Super Tour Mar 2021 qualifying · STU 1:32.913 Tony Ave, Super Tour Mar 2026 qualifying · FP 1:37.224 Michael Kamalian, Super Tour Mar 2021 race

1:301:351:401:451:501:552:002:052:102:152:202:252:302:3555 rule changes between Super Tour Mar 2021 and Super Tour Mar 202255 ▾34 rule changes between Super Tour Mar 2022 and Super Tour Mar 202334 ▾37 rule changes between Super Tour Mar 2023 and Super Tour Mar 202437 ▾48 rule changes between Super Tour Mar 2024 and Super Tour Mar 202548 ▾58 rule changes between Super Tour Mar 2025 and Super Tour Mar 202658 ▾AS race best at Super Tour Mar 2021: 1:34.734 (Tom Ellis)AS race best at Super Tour Mar 2022: 1:35.993 (Gregory Eaton)AS race best at Super Tour Mar 2024: 2:00.265 (Phillip Waters)AS race best at Super Tour Mar 2025: 1:35.351 (Thomas J Ellis)AS race best at Super Tour Mar 2026: 1:34.642 (Michael Kamalian)AS qualifying best at Super Tour Mar 2021: 1:34.231 (Tom Ellis)AS qualifying best at Super Tour Mar 2022: 1:36.346 (Gregory Eaton)AS qualifying best at Super Tour Mar 2024: 1:44.301 (Phillip Waters)AS qualifying best at Super Tour Mar 2025: 1:35.467 (Thomas J Ellis)AS qualifying best at Super Tour Mar 2026: 2:28.404 (Michael Kamalian)STU race best at Super Tour Mar 2021: 1:36.703 (David Brand)STU race best at Super Tour Mar 2022: 1:34.081 (Johan Schwartz)STU race best at Super Tour Mar 2023: 1:35.081 (Anthony Geraci)STU race best at Super Tour Mar 2024: 1:37.732 (David Fiorelli)STU race best at Super Tour Mar 2025: 1:33.937 (Richard Astacio)STU race best at Super Tour Mar 2026: 1:34.356 (Johan Schwartz)STU qualifying best at Super Tour Mar 2021: 1:36.582 (David Brand)STU qualifying best at Super Tour Mar 2022: 1:34.986 (Johan Schwartz)STU qualifying best at Super Tour Mar 2023: 1:35.710 (Anthony Geraci)STU qualifying best at Super Tour Mar 2024: 1:37.519 (Jorge Nazario)STU qualifying best at Super Tour Mar 2025: 1:33.044 (Richard Astacio)STU qualifying best at Super Tour Mar 2026: 1:32.913 (Tony Ave)FP race best at Super Tour Mar 2021: 1:37.224 (Michael Kamalian)FP race best at Super Tour Mar 2022: 1:38.391 (Perry Simonds)FP race best at Super Tour Mar 2023: 1:38.568 (Mason Workman)FP race best at Super Tour Mar 2024: 1:37.623 (Ken Kannard)FP race best at Super Tour Mar 2025: 1:38.438 (Ken Kannard)FP race best at Super Tour Mar 2026: 1:39.386 (Cliff Ira)FP qualifying best at Super Tour Mar 2021: 1:38.918 (Michael Kamalian)FP qualifying best at Super Tour Mar 2022: 1:39.464 (Perry Simonds)FP qualifying best at Super Tour Mar 2023: 1:38.342 (Mason Workman)FP qualifying best at Super Tour Mar 2024: 1:37.924 (Ken Kannard)FP qualifying best at Super Tour Mar 2025: 1:38.226 (Mason Workman)FP qualifying best at Super Tour Mar 2026: 1:39.075 (Ken Kannard)Super Tour Mar 2021Super Tour Mar2021Super Tour Mar 2022Super Tour Mar2022Super Tour Mar 2023Super Tour Mar2023Super Tour Mar 2024Super Tour Mar2024Super Tour Mar 2025Super Tour Mar2025Super Tour Mar 2026Super Tour Mar2026
ASSRFSTUFPsolid race · dashed qualifying · slower is lower
58%60%62%64%66%68%70%72%74%76%78%80%82%84%86%88%90%92%94%96%98%100%102%104%106%108%110%55 rule changes between Super Tour Mar 2021 and Super Tour Mar 202255 ▾34 rule changes between Super Tour Mar 2022 and Super Tour Mar 202334 ▾37 rule changes between Super Tour Mar 2023 and Super Tour Mar 202437 ▾48 rule changes between Super Tour Mar 2024 and Super Tour Mar 202548 ▾58 rule changes between Super Tour Mar 2025 and Super Tour Mar 202658 ▾AS race best at Super Tour Mar 2021: 100.0% of AS's (Tom Ellis)AS race best at Super Tour Mar 2022: 100.0% of AS's (Gregory Eaton)AS race best at Super Tour Mar 2024: 100.0% of AS's (Phillip Waters)AS race best at Super Tour Mar 2025: 100.0% of AS's (Thomas J Ellis)AS race best at Super Tour Mar 2026: 100.0% of AS's (Michael Kamalian)AS qualifying best at Super Tour Mar 2021: 100.0% of AS's (Tom Ellis)AS qualifying best at Super Tour Mar 2022: 100.0% of AS's (Gregory Eaton)AS qualifying best at Super Tour Mar 2024: 100.0% of AS's (Phillip Waters)AS qualifying best at Super Tour Mar 2025: 100.0% of AS's (Thomas J Ellis)AS qualifying best at Super Tour Mar 2026: 100.0% of AS's (Michael Kamalian)STU race best at Super Tour Mar 2021: 102.1% of AS's (David Brand)STU race best at Super Tour Mar 2022: 98.0% of AS's (Johan Schwartz)STU race best at Super Tour Mar 2024: 81.3% of AS's (David Fiorelli)STU race best at Super Tour Mar 2025: 98.5% of AS's (Richard Astacio)STU race best at Super Tour Mar 2026: 99.7% of AS's (Johan Schwartz)STU qualifying best at Super Tour Mar 2021: 102.5% of AS's (David Brand)STU qualifying best at Super Tour Mar 2022: 98.6% of AS's (Johan Schwartz)STU qualifying best at Super Tour Mar 2024: 93.5% of AS's (Jorge Nazario)STU qualifying best at Super Tour Mar 2025: 97.5% of AS's (Richard Astacio)STU qualifying best at Super Tour Mar 2026: 62.6% of AS's (Tony Ave)FP race best at Super Tour Mar 2021: 102.6% of AS's (Michael Kamalian)FP race best at Super Tour Mar 2022: 102.5% of AS's (Perry Simonds)FP race best at Super Tour Mar 2024: 81.2% of AS's (Ken Kannard)FP race best at Super Tour Mar 2025: 103.2% of AS's (Ken Kannard)FP race best at Super Tour Mar 2026: 105.0% of AS's (Cliff Ira)FP qualifying best at Super Tour Mar 2021: 105.0% of AS's (Michael Kamalian)FP qualifying best at Super Tour Mar 2022: 103.2% of AS's (Perry Simonds)FP qualifying best at Super Tour Mar 2024: 93.9% of AS's (Ken Kannard)FP qualifying best at Super Tour Mar 2025: 102.9% of AS's (Mason Workman)FP qualifying best at Super Tour Mar 2026: 66.8% of AS's (Ken Kannard)Super Tour Mar 2021Super Tour Mar2021Super Tour Mar 2022Super Tour Mar2022Super Tour Mar 2023Super Tour Mar2023Super Tour Mar 2024Super Tour Mar2024Super Tour Mar 2025Super Tour Mar2025Super Tour Mar 2026Super Tour Mar2026
ASSRFSTUFPsolid race · dashed qualifying · each class's best lap as a share of AS's at the same event (the reference class, changeable above); 100% is level, higher is quicker
EventASSRFSTUFP
Qual bestRace bestTrapQual bestRace bestTrapvs AS% of ASQual bestRace bestTrapvs AS% of ASQual bestRace bestTrapvs AS% of AS
Super Tour Mar 2026 ST26MAR062026-03-062:28.404Michael Kamalian · only car+52.937s (+55.45%)1:34.642Michael Kamalian · only car-0.709s (-0.74%)140.9Michael Kamalian+2.4 mph (+1.7%)1:32.913Tony Ave · fastest of 13 · top 5 within 3.4s-0.131s (-0.14%)1:34.356Johan Schwartz · fastest of 14 · top 5 within 1.7s+0.419s (+0.45%)139.8Hugh Stewart+10.0 mph (+7.7%)-0.286squal -55.491s99.7%qual 62.6%1:39.075Ken Kannard · fastest of 4 · top 4 within 2.6s+0.849s (+0.86%)1:39.386Cliff Ira · fastest of 4 · top 4 within 2.8s+0.948s (+0.96%)124.2Cliff Ira+5.8 mph (+4.9%)+4.744squal -49.329s105.0%qual 66.8%
58 rule changes (AS: 11, SRF: 4, STU: 14, FP: 29)17 weight · 10 cars added · 7 engine · 6 induction · 3 tyres & wheels · 10 wording · 5 other · AS Spec Lines reorganized for 2026; detailed chassis, engine, weight, wheelbase, tire and brake specifications moved to main rules and engine build sheets. · FP Fiat X-1/9 1300 and 1500 intake and exhaust valve sizes corrected to 36.3/(1.43) and 31.2-33.3/(1.23-1.31). · FP Fiat X-1/9 & Bertone dual carburetors choke size increases from 28mm to 30mm on intake runner manifold. · SRF3 spark plugs limited to NGK LTR7IX-11 P/N G301041 only; washers and sealing rings prohibited. · STU Mazda MZR engines may now use Fab 9 Elite NC MX5 Performance Intake manifold as alternative option. · AS GM LM7 5.3L gains Edelbrock 71187 intake manifold, MSD 6014 ignition box, Holly 4776 carb option under full prep spec line. · FP adds Toyota 5E 1497cc DOHC engine, 1900 lbs, 23mm restrictor, SIR fuel induction. · FP class adds Toyota 4E DOHC 1331 cc engine, 1900 lbs minimum weight, unrestricted fuel induction. · FP Fiat X1/9 fuel injection carburetors simplified to one 36 or 40 DCNF option; exhaust valve enlarged to 33.0/1.30. · AS Ford Mustang and Mercury Capri with Restricted Prep engines get 61 mm restrictor, down from 64 mm. · 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. · AS Ford Mustang GT 94-04 Restricted Prep Engine now permits Ford Motorsport M-6250-F303 camshaft. · EP Triumph TR2–TR4A may use 5-speed gearbox without overdrive; Weber carburetors and weight reference deleted. · EP BMW Z3 2.5L and other models get smaller restrictors, 50mm to 55mm, and Z3 2.5L weight rises 50 to 78 lbs. · FP Lancia Scorpion minimum weight cut to 1950 lbs from 2030 lbs. · FP VW Rabbit Convertible no longer required to remove factory roll bar. · FP Acura Integra and Honda Civic models gain 50–79 lbs minimum weight; Mazda Miata and Mercury Capri compression ratio to 11.0:1 and valve lift to .425". · FP Honda D15, D16, B16A, B18 engines gain 105–120 lbs minimum weight across seven configurations. · 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. · AS Cadillac CTS-V 04-07 Restricted Prep minimum weight drops to 3400 lbs. · EP Nissan 280Z minimum weight lowered to 2400 lbs, 2460 lbs with *, 2520 lbs with **. · EP Mazda MX-5 1.8L 90-97 minimum weight reduced to 2125 lbs. · HP Spec Lines Austin-Healey Sprite/Midget 1098cc minimum weight drops to 1550 lbs. · HP Volvo 142 P-1800 engine gains compression ratio limit 12.0:1 and valve lift limit .425 inch. · HP Mini DOHC 1.6 valve lift limit drops to .390" from .450". · FP Scirocco 83–88 classified Prep Level 1: 1733–1803 lbs, 1715–1780 cc, iron block, aluminium head, carburetted or fuel injected. · FP and HP Volkswagen Rabbit descriptions updated to clarify Cabriolet body style inclusion. · EP, FP, HP: rear drum-to-disc brake conversion clarified; rotors solid, diameter limited to largest front rotor permitted. · EP Ford Mustang 94-98 fuel injected throttle body inside diameter set to 60. · FP Volkswagen Scirocco: remove two weight tiers at 1733 and 1803 lbs, two engine options, and 13-inch wheel option; allow 15-inch wheels. · STU Honda K24 engine swap weight increases by 2 percent, effective November 1, 2025. · HP Plymouth Arrow gains 4 or 5 speed transmission option specification. · Appendix G.2.3 clarifies rim width and diameter are absolute maximums; wording corrected from 'is' to 'are'. · EP, FP, HP throttle body inside dimensions and butterfly now allow +/-.25mm tolerance from stock. · SRF3 adds HD Oil Cooler P/N G1148500 option alongside standard P/N G480503, no fan permitted. · 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. · AS Ford Mustang GT 5.0 2018- minimum weight reduced to 3525 lbs. · EP BMW Z4 03-05 gains 52mm flat plate intake restrictor. · EP Fiat 124 Spider Competition 1600 and 2000 minimum weight drops 50 lbs to 2000; carburetors now allow 36mm chokes instead of 34mm. · 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. · AS Ford Mustang GT 05-14 Restricted Prep Engine gains additional gear ratio option: 3.66, 2.43, 1.69, 1.32, 1.00, .65. · HP Fiat X-1/9 and Bertone 1500 minimum weights reduced to 1740 lbs, 1784 lbs, 1827 lbs; 1300 models to 1600, 1640, 1680 lbs; additional 1300 and 1500 specs to 2010, 1900 lbs. · AS Ford Mustang GT 5.0L 15-17 flat plate restrictor reduces from 67mm to 64mm. · AS LS1/LS6 intakes added for 5.3L truck engine: part numbers 12561269 and 88894095. · 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. · AS Flotek head value seat cutting dimensions figure updated for consistency. · AS class notes cleaned: fuel cell and ECM specifications removed from multiple Camaro, Firebird, Challenger and Mustang variants. · Chevrolet Spark 16-22 classified in HP Pre at 1850 lbs base, 1896 lbs modified, 1943 lbs. · HP Ford Festiva 88-93 minimum weight lowered to 1600 lbs, competition weight to 1640, prepared weight to 1680; compression ratio raised to 11.0:1. · SRF drivers with disabilities may modify seat and controls for safety and comfort with SCCA approval, noted in logbook, for that driver only. · SRF SADEV-SRF3 6-speed sequential transmission: effective date clarified to 1 April 2025 onward.showhide
  • AS Re-Organization of AS Spec lines for 2026 #39887wordingwordingAS Spec Lines reorganized for 2026; detailed chassis, engine, weight, wheelbase, tire and brake specifications moved to main rules and engine build sheets.
  • FP Correct Valve Sizes on FP Fiat x19 1300 and 1500 #39850otherotherFP Fiat X-1/9 1300 and 1500 intake and exhaust valve sizes corrected to 36.3/(1.43) and 31.2-33.3/(1.23-1.31).
  • FP Dual Carburetor Adjustments #39851inductionfaster · inductionFP Fiat X-1/9 & Bertone dual carburetors choke size increases from 28mm to 30mm on intake runner manifold.
  • SRF SRF3 Spark Plugs #39899engineengineSRF3 spark plugs limited to NGK LTR7IX-11 P/N G301041 only; washers and sealing rings prohibited.
  • STU Fab 9 Racing Intake Manifold in STU #39767cars addedaddedSTU Mazda MZR engines may now use Fab 9 Elite NC MX5 Performance Intake manifold as alternative option.
  • AS Edelbrock manifold (& timing kit) to Chevy LS Spec Lines Request #39055cars addedaddedAS GM LM7 5.3L gains Edelbrock 71187 intake manifold, MSD 6014 ignition box, Holly 4776 carb option under full prep spec line.
  • FP Request Toyota 5E Series Engines #38208otheraddedFP adds Toyota 5E 1497cc DOHC engine, 1900 lbs, 23mm restrictor, SIR fuel induction.
  • FP Request for Toyota 4E Series Engines #38209cars addedaddedFP class adds Toyota 4E DOHC 1331 cc engine, 1900 lbs minimum weight, unrestricted fuel induction.
  • FP Dual Carbs for the Fiat X1/9 #39593enginefaster · engineFP Fiat X1/9 fuel injection carburetors simplified to one 36 or 40 DCNF option; exhaust valve enlarged to 33.0/1.30.
  • AS Restrictor Plate Change for Gen 2 Ford Coyote Engine #39501inductionslower · inductionAS Ford Mustang and Mercury Capri with Restricted Prep engines get 61 mm restrictor, down from 64 mm.
  • 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.
  • AS 1994 Mustang Spec Line Request #39104engineadded · engineAS Ford Mustang GT 94-04 Restricted Prep Engine now permits Ford Motorsport M-6250-F303 camshaft.
  • FP TR2 Notes E&O #39180wordingwordingEP Triumph TR2–TR4A may use 5-speed gearbox without overdrive; Weber carburetors and weight reference deleted.
  • FP Balance of Power #39187induction +50 lbsslower · inductionEP BMW Z3 2.5L and other models get smaller restrictors, 50mm to 55mm, and Z3 2.5L weight rises 50 to 78 lbs.
  • FP Competition Adjustment Request #39259weight -80 lbsfaster · weightFP Lancia Scorpion minimum weight cut to 1950 lbs from 2030 lbs.
  • FP Factory Roll Bar Removal on VW Convertible #39268wordingwordingFP VW Rabbit Convertible no longer required to remove factory roll bar.
  • FP FP Parity Request #39325weight +50 lbsslower · weightFP Acura Integra and Honda Civic models gain 50–79 lbs minimum weight; Mazda Miata and Mercury Capri compression ratio to 11.0:1 and valve lift to .425".
  • FP Adjust former-GTL Honda's with B/D-Series Engines #39374weightslower · weightFP Honda D15, D16, B16A, B18 engines gain 105–120 lbs minimum weight across seven configurations.
  • 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.
  • AS Cadillac CTS-V BOP Weight Change #38640weight -50 lbsfaster · weightAS Cadillac CTS-V 04-07 Restricted Prep minimum weight drops to 3400 lbs.
  • FP Please Lower Weight of 280Z #38871weight -160 lbsfaster · weightEP Nissan 280Z minimum weight lowered to 2400 lbs, 2460 lbs with *, 2520 lbs with **.
  • FP Miata Weight Adjustment Follow Up #38949weight -25 lbsfaster · weightEP Mazda MX-5 1.8L 90-97 minimum weight reduced to 2125 lbs.
  • FP Weight Break for 1098 Midget / Sprite #38970weight -80 lbsfaster · weightHP Spec Lines Austin-Healey Sprite/Midget 1098cc minimum weight drops to 1550 lbs.
  • FP HP Volvo 142 spec omission #38994engineslower · engineHP Volvo 142 P-1800 engine gains compression ratio limit 12.0:1 and valve lift limit .425 inch.
  • FP HP Mini DOHC 1.6 #38996engineslower · engineHP Mini DOHC 1.6 valve lift limit drops to .390" from .450".
  • FP 83-88 FP Scirocco Spec Line Creation #38997cars addedaddedFP Scirocco 83–88 classified Prep Level 1: 1733–1803 lbs, 1715–1780 cc, iron block, aluminium head, carburetted or fuel injected.
  • FP Add to Rabbit description #39019wordingwordingFP and HP Volkswagen Rabbit descriptions updated to clarify Cabriolet body style inclusion.
  • FP Clean-up 9.1.5.E.7e #39025otherotherEP, FP, HP: rear drum-to-disc brake conversion clarified; rotors solid, diameter limited to largest front rotor permitted.
  • FP Add TB size to Ford Mustang (94-98) Spec Line #39130inductionadded · inductionEP Ford Mustang 94-98 fuel injected throttle body inside diameter set to 60.
  • FP Correct Existing VW Scirocco Spec Line #39140cars addedremoved · cars addedFP Volkswagen Scirocco: remove two weight tiers at 1733 and 1803 lbs, two engine options, and 13-inch wheel option; allow 15-inch wheels.
  • 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.
  • FP HP Plymouth Arrow spec omission #38995cars addedaddedHP Plymouth Arrow gains 4 or 5 speed transmission option specification.
  • FP Add Wheel Diameter to Appendix G #39008wordingwordingAppendix G.2.3 clarifies rim width and diameter are absolute maximums; wording corrected from 'is' to 'are'.
  • FP Add TB ID tolerance to general Prod rules #39009wordingaddedEP, FP, HP throttle body inside dimensions and butterfly now allow +/-.25mm tolerance from stock.
  • SRF Add HD Oil Cooler #38979engineadded · engineSRF3 adds HD Oil Cooler P/N G1148500 option alongside standard P/N G480503, no fan permitted.
  • 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.
  • AS RE: Previous Letter 37695 Update #38245weight -75 lbsfaster · weightAS Ford Mustang GT 5.0 2018- minimum weight reduced to 3525 lbs.
  • FP BMW Z4 update #38490inductionslower · inductionEP BMW Z4 03-05 gains 52mm flat plate intake restrictor.
  • FP EP Fiat 124 Spider Competition Adjustment Request #38498weight -50 lbsfaster · weightEP Fiat 124 Spider Competition 1600 and 2000 minimum weight drops 50 lbs to 2000; carburetors now allow 36mm chokes instead of 34mm.
  • 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.
  • AS Errors and Omissions #38234otheraddedAS Ford Mustang GT 05-14 Restricted Prep Engine gains additional gear ratio option: 3.66, 2.43, 1.69, 1.32, 1.00, .65.
  • FP Base Weight Adjustment for H-Production X1/9 Spec Lines #38255weight -50 lbsfaster · weightHP Fiat X-1/9 and Bertone 1500 minimum weights reduced to 1740 lbs, 1784 lbs, 1827 lbs; 1300 models to 1600, 1640, 1680 lbs; additional 1300 and 1500 specs to 2010, 1900 lbs.
  • AS Errors and Omission #38055inductionslower · inductionAS Ford Mustang GT 5.0L 15-17 flat plate restrictor reduces from 67mm to 64mm.
  • AS Request to Add LS1/LS6 Intakes for 5.3L Truck Engine EnO #38197cars addedaddedAS LS1/LS6 intakes added for 5.3L truck engine: part numbers 12561269 and 88894095.
  • 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.
  • AS Flotek Head Plunge Cut Inconsistencies #37502wordingwordingAS Flotek head value seat cutting dimensions figure updated for consistency.
  • AS Notes clean up #37693wordingwordingAS class notes cleaned: fuel cell and ECM specifications removed from multiple Camaro, Firebird, Challenger and Mustang variants.
  • FP Request for Classification of Chevrolet Spark #37755cars addedaddedChevrolet Spark 16-22 classified in HP Pre at 1850 lbs base, 1896 lbs modified, 1943 lbs.
  • FP Request to Lower Ford Festiva Minimum Weight to 1600 LBS #37939weight -100 lbsfaster · weightHP Ford Festiva 88-93 minimum weight lowered to 1600 lbs, competition weight to 1640, prepared weight to 1680; compression ratio raised to 11.0:1.
  • SRF Driver Safety & Comfort #37966otheraddedSRF drivers with disabilities may modify seat and controls for safety and comfort with SCCA approval, noted in logbook, for that driver only.
  • SRF Update SADEV transmission specs #37992wordingwordingSRF SADEV-SRF3 6-speed sequential transmission: effective date clarified to 1 April 2025 onward.
Super Tour Mar 2025 ST25MAR072025-03-071:35.467Thomas J Ellis · fastest of 4 · top 4 within 2.7s-8.834s (-8.47%)1:35.351Thomas J Ellis · fastest of 4 · top 4 within 1.1s-24.914s (-20.72%)138.6James Jost+8.6 mph (+6.6%)1:33.044Richard Astacio · fastest of 9 · top 5 within 3.8s-4.475s (-4.59%)1:33.937Richard Astacio · fastest of 8 · top 5 within 3.5s-3.795s (-3.88%)129.8David Fiorelli+1.8 mph (+1.4%)-1.414squal -2.423s98.5%qual 97.5%1:38.226Mason Workman · fastest of 5 · top 5 within 3.6s+0.302s (+0.31%)1:38.438Ken Kannard · fastest of 5 · top 5 within 3.2s+0.815s (+0.83%)118.3Ken Kannard-0.7 mph (-0.6%)+3.087squal +2.759s103.2%qual 102.9%
48 rule changes (AS: 12, SRF: 6, STU: 11, FP: 19)12 cars added · 7 engine · 7 induction · 5 weight · 3 tyres & wheels · 1 suspension & brakes · 10 wording · 3 other · AS removes 'Any ECM maybe used' note from five Cadillac and Chevrolet/Pontiac V8 Restricted Prep models. · EP BMW Z3 2.5L, Z3 2.8L, 328i E36/E46, 325i E36/E46 intake restrictors reduced 4mm each, to 52–58mm. · FP Acura Integra and Honda Civic models restricted from 55mm to 51mm intake; Del Sol VTEC weight raised to 2290, 2347, 2405 lbs. · EP, FP, HP may use any interior or exterior mirror meeting rule 9.3.36. · EP Honda S2000 1997cc minimum weight drops 75 lbs to 2375; 2157cc drops 60 lbs to 2450. · EP Mazda MX-5 Miata 99-05 minimum weight reduced to 2100 lbs, 2153 lbs with power, 2205 lbs modified. · FP Volkswagen Jetta Mark IV 4dr FWD added to GTL-FP Cars classification with 98.2 in wheelbase. · FP adds optional induction chokes as alternative to SIR, same size as listed restrictor. · 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. · EP BMW models now require flat plate intake restrictors: Z3 2.5L 52mm, Z3 2.8L 55mm, 328i E36 58mm, 328i/ci E46 58mm, 325i E46 56mm, 325i E36 56mm, 325is M-Technic 56mm. · AS Ford Mustang and Cobra Coyote engine restrictor increases to 80mm from 67mm or 64mm. · AS Mustang GT 05-14 Restricted loses 300 lbs engine; 15-17 and 2018+ models lose 61mm and 60mm restrictors respectively. · AS class: multiple American muscle cars gain additional allowed gear ratio options across model years and prep levels. · AS LS-engine cars gain ECU freedom: CTS-V, Camaro, Firebird (70–02) and Camaro SS may use any ECM. · EP BMW 325i/is E30 84-91 weight reduced to 2150 lbs base, 2204 lbs with turbo, 2258 lbs supercharged. · FP Sprite and Midget 1275cc and 1500cc bore, stroke, displacement, and valve specifications corrected to factory dimensions. · F Production now permits GT-Lite cars meeting Appendix N specs to compete, governed by Appendix N not PCS 9.1.5. · 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. · 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. · HP 1275 Spridget compression ratio raised to 12.0:1; 1098cc also raised to 12.0:1. · STU Mini Cooper S SC: 1900 stock pulley spec to 2.565 diameter; 2100 now permits 2.285 diameter pulley. · FP Honda CRX/CRX Si 84-87 block material changes from iron to aluminium. · SRF3 air filter rule removes K&N RC-9160 option, specifies Weems P/N WM301020 only. · SRF Wilwood vented rotor minimum thickness increases to 13.25mm, 0.522 inches. · SRF3 Hoosier decal placement changed from four logos on nose and tail to three logos on sides and center front. · AS Mustang GT 05-14 Restricted Prep and 2018- gain alternate transmission ratio options. · FE and SRF protest fee rules redirected to GCR section 8.3.1.D for fees and procedure. · SRF Hoosier contingency decal requirement reduced from four decals in specific locations to three decals with simplified placement. · HP Volkswagen Golf and Jetta 85-92 track correction: front 1537 mm (60.5 in.), rear 1529 mm (60.2 in.). · SRF wet tyres: front P185/60R13 H20 or W2 and rear P205/60R13 H20 or W2 removed; front P185/65R13 W2 and rear P205/60R13 W2 now required. Hoosier decal placement specified. · STU RWD turbo cars no longer required to reduce inlet restrictor by 1 mm from table minimum. · AS adds 2018-23 Ford Mustang GT 5.0L at 3600 lbs, 275 tire, 60mm restrictor, optional Brembo front brakes. · Nissan 300ZX 84–89 added to EP, 2550–2678 lbs, 2960 cc SOHC, fuel injection, 12.0:1 compression, 0.500" valve lift limit. · Mazda RX-7 92-97 added to EP Prep as Level 2 rotary 13B 6-port, 2200–2310 lbs, carb or fuel injection, 42 mm choke. · EP Mazda RX-8 (04-11) alternate spec line removed; single spec line retained. · AS Chevrolet Camaro 1LE (2016-) added with 3600 lbs minimum weight, 275 tires, 60mm restrictor, 345/338mm brakes. · AS Chevrolet/Pontiac Camaro & Firebird 82–92 5.7L LS1 classified: 3200 lbs, 13.1×1.27 disc brakes, 17 in max wheel, 65 mm restrictor, SLP intake lid permitted. · AS Chevrolet Camaro, Firebird, and Ford Mustang now permit Flo Tek cylinder heads in multiple generations. · FP Honda CRX 84-87 plastic front header nose panel, rocker skirts, door caps can now be replica alternate material stock appearance. · FP Acura Integra 90-01 and Honda Civic Del Sol VTEC, Civic Si 99-00 require 55mm flat plate intake restrictor. · AS Camaro, Firebird 93-02 and GTO 04-06 add approved LS1 connecting rod part numbers to Notes. · AS Cadillac CTS-V, Chevy Camaro SS V8, Dodge Challenger, Ford Mustang GT 5.0L, Pontiac GTO allowed 11" wheels until 3/1/25.showhide
  • AS Race memo #37902wordingwordingAS removes 'Any ECM maybe used' note from five Cadillac and Chevrolet/Pontiac V8 Restricted Prep models.
  • FP Request Competition Adjustment to BMW Z3 2.5L #37120inductionslower · inductionEP BMW Z3 2.5L, Z3 2.8L, 328i E36/E46, 325i E36/E46 intake restrictors reduced 4mm each, to 52–58mm.
  • FP FP Class Adjustments #37458inductionslower · inductionFP Acura Integra and Honda Civic models restricted from 55mm to 51mm intake; Del Sol VTEC weight raised to 2290, 2347, 2405 lbs.
  • FP Interpretation of Production Rules on Mirrors #37235wordingaddedEP, FP, HP may use any interior or exterior mirror meeting rule 9.3.36.
  • FP Weight Reduction for Honda S2000 #37466weightfaster · weightEP Honda S2000 1997cc minimum weight drops 75 lbs to 2375; 2157cc drops 60 lbs to 2450.
  • FP Mazda 1999 Miata 1.8L #37488weight -50 lbsfaster · weightEP Mazda MX-5 Miata 99-05 minimum weight reduced to 2100 lbs, 2153 lbs with power, 2205 lbs modified.
  • FP Errors & Omissions #37648cars addedaddedFP Volkswagen Jetta Mark IV 4dr FWD added to GTL-FP Cars classification with 98.2 in wheelbase.
  • FP GTL/FP consolidation 2025 Rules #37659inductionadded · inductionFP adds optional induction chokes as alternative to SIR, same size as listed restrictor.
  • 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.
  • FP Effective date for Jan 2025 GCR updates #37654inductionslower · inductionEP BMW models now require flat plate intake restrictors: Z3 2.5L 52mm, Z3 2.8L 55mm, 328i E36 58mm, 328i/ci E46 58mm, 325i E46 56mm, 325i E36 56mm, 325is M-Technic 56mm.
  • AS Increase Coyote Engine Restrictor to 80mm #36177enginefaster · engineAS Ford Mustang and Cobra Coyote engine restrictor increases to 80mm from 67mm or 64mm.
  • AS Performance Pack for 2015+ Mustang #36867enginefaster · engineAS Mustang GT 05-14 Restricted loses 300 lbs engine; 15-17 and 2018+ models lose 61mm and 60mm restrictors respectively.
  • AS Gear Ratios #37131otheraddedAS class: multiple American muscle cars gain additional allowed gear ratio options across model years and prep levels.
  • AS ECU specs for LS engine #37208engineadded · engineAS LS-engine cars gain ECU freedom: CTS-V, Camaro, Firebird (70–02) and Camaro SS may use any ECM.
  • FP Request to Reduce Weight of BMW 325i/is E30 (84-91) Spec Line #37119weight -50 lbsfaster · weightEP BMW 325i/is E30 84-91 weight reduced to 2150 lbs base, 2204 lbs with turbo, 2258 lbs supercharged.
  • FP Fix Error in Spridget Spec Line #37437wordingwordingFP Sprite and Midget 1275cc and 1500cc bore, stroke, displacement, and valve specifications corrected to factory dimensions.
  • FP Create ruleset that allows GTL cars to run in FP #37485cars addedaddedF Production now permits GT-Lite cars meeting Appendix N specs to compete, governed by Appendix N not PCS 9.1.5.
  • 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.
  • 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.
  • FP 1275 HP Spridget Level 2 Only #36518enginefaster · engineHP 1275 Spridget compression ratio raised to 12.0:1; 1098cc also raised to 12.0:1.
  • 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.
  • FP Errors/emissions Honda Civic/CRX #36700enginefaster · engineFP Honda CRX/CRX Si 84-87 block material changes from iron to aluminium.
  • SRF Update SRF3 Air Filter Rule #36681wordingremovedSRF3 air filter rule removes K&N RC-9160 option, specifies Weems P/N WM301020 only.
  • SRF Update SRF Brake Rotor Thickness #36687suspension & brakessuspension & brakesSRF Wilwood vented rotor minimum thickness increases to 13.25mm, 0.522 inches.
  • SRF Hoosier Tire Decal Placement #36739wordingwordingSRF3 Hoosier decal placement changed from four logos on nose and tail to three logos on sides and center front.
  • AS Mustang transmission ratios #36662otheraddedAS Mustang GT 05-14 Restricted Prep and 2018- gain alternate transmission ratio options.
  • SRF Protest Fee Clarification #36540wordingwordingFE and SRF protest fee rules redirected to GCR section 8.3.1.D for fees and procedure.
  • SRF Update to Letter 36619 with new Hoosier Contingency Decal Info #36624wordingwordingSRF Hoosier contingency decal requirement reduced from four decals in specific locations to three decals with simplified placement.
  • FP Errant entry in HP production line item #36231wordingwordingHP Volkswagen Golf and Jetta 85-92 track correction: front 1537 mm (60.5 in.), rear 1529 mm (60.2 in.).
  • SRF Update Rain Tire Rule and Hoosier Decal Placement #36436tyres & wheelstyres & wheelsSRF wet tyres: front P185/60R13 H20 or W2 and rear P205/60R13 H20 or W2 removed; front P185/65R13 W2 and rear P205/60R13 W2 now required. Hoosier decal placement specified.
  • STU RWD Turbo Disadvantage #36255inductionfaster · inductionSTU RWD turbo cars no longer required to reduce inlet restrictor by 1 mm from table minimum.
  • AS Request for Classification of 2018-2023 mustang In #35764cars addedaddedAS adds 2018-23 Ford Mustang GT 5.0L at 3600 lbs, 275 tire, 60mm restrictor, optional Brembo front brakes.
  • FP NIssan 300ZX Z31 to EP #35830cars addedaddedNissan 300ZX 84–89 added to EP, 2550–2678 lbs, 2960 cc SOHC, fuel injection, 12.0:1 compression, 0.500" valve lift limit.
  • FP RX7 1993 and Up Request In EP Spec Lines, classify #36031cars addedaddedMazda RX-7 92-97 added to EP Prep as Level 2 rotary 13B 6-port, 2200–2310 lbs, carb or fuel injection, 42 mm choke.
  • FP Clean-up Multiple EP RX-8 Spec Lines In EP #36156cars addedremoved · cars addedEP Mazda RX-8 (04-11) alternate spec line removed; single spec line retained.
  • AS 6th gen Camaro limited prep #35733cars addedaddedAS Chevrolet Camaro 1LE (2016-) added with 3600 lbs minimum weight, 275 tires, 60mm restrictor, 345/338mm brakes.
  • AS Chevrolet/Pontiac Camaro & Firebird (82-92) 5.7L V8 LS1 Alum BLK #35825cars addedaddedAS Chevrolet/Pontiac Camaro & Firebird 82–92 5.7L LS1 classified: 3200 lbs, 13.1×1.27 disc brakes, 17 in max wheel, 65 mm restrictor, SLP intake lid permitted.
  • AS Full Prep Head #35891engineadded · engineAS Chevrolet Camaro, Firebird, and Ford Mustang now permit Flo Tek cylinder heads in multiple generations.
  • FP Request to Replace CRX Plastic Panels #35876cars addedaddedFP Honda CRX 84-87 plastic front header nose panel, rocker skirts, door caps can now be replica alternate material stock appearance.
  • FP FP data and parity #35896inductionadded · inductionFP Acura Integra 90-01 and Honda Civic Del Sol VTEC, Civic Si 99-00 require 55mm flat plate intake restrictor.
  • AS Restricted Prep Aftermarket Parts Request #35682otheraddedAS Camaro, Firebird 93-02 and GTO 04-06 add approved LS1 connecting rod part numbers to Notes.
  • AS Allowance of 11 #35824tyres & wheelsfaster · tyres & wheelsAS Cadillac CTS-V, Chevy Camaro SS V8, Dodge Challenger, Ford Mustang GT 5.0L, Pontiac GTO allowed 11" wheels until 3/1/25.
Super Tour Mar 2024 ST24MAR082024-03-081:44.301Phillip Waters · only car+7.955s (+8.26%)2:00.265Phillip Waters · only car+24.272s (+25.29%)130.0Phillip Waters-13.7 mph (-9.5%)1:37.519Jorge Nazario · fastest of 7 · top 5 within 5.3s+1.809s (+1.89%)1:37.732David Fiorelli · fastest of 5 · top 5 within 7.0s+2.651s (+2.79%)128.0David Fiorelli-7.4 mph (-5.5%)-22.533squal -6.782s81.3%qual 93.5%1:37.924Ken Kannard · fastest of 4 · top 4 within 7.1s-0.418s (-0.43%)1:37.623Ken Kannard · fastest of 5 · top 5 within 31.1s-0.945s (-0.96%)119.0Ken Kannard-3.6 mph (-2.9%)-22.642squal -6.377s81.2%qual 93.9%
37 rule changes (AS: 8, SRF: 6, STU: 5, FP: 18)9 weight · 6 cars added · 3 tyres & wheels · 2 aero · 1 engine · 1 induction · 1 removed · 1 suspension & brakes · 6 wording · 7 other · Chevrolet Camaro, Pontiac Firebird 70–81 Full Prep classified in AS at 3400–3600 lbs with 108.0 wheelbase, specific head castings, and suspension modifications permitted. · AS class adds fuel cell location notes to multiple Cadillac, Chevrolet, Dodge and Ford models: cells within 24 inches of standard tank. · Chevrolet Camaro 6th gen Full Prep added to AS class at 3400 lbs base or 3600 lbs with built engine. · AS class: Ford Mustang GT 05-14 Restricted prep added; Cadillac CTS-V 04-07 to 3450 lbs; Camaro/Firebird variants reconfigured with weight and notes changes; Dodge Challenger 08-20 restrictor 76mm to 80mm; Ford Mustang variants updated wei… · HP removes four redundant VW spec lines: Rabbit Cabriolet 1780, Scirocco 1588, Scirocco 1780 8-valve 83-88, Scirocco 1588. · FP Mazda Protégé ES (01-03) renamed to Mazda Protégé ES/5 (01-03). · 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. · HP Honda Civic 1.5 1988-91 minimum weight drops 70 lbs to 2175; also 2-speed and 3-speed minimums cut 72 and 73 lbs. · STL and STU now permit electric power steering pumps, OEM electric-assisted steering, or column-mounted electric steering assist systems. · EP BMW Z3 2.5L minimum weight increased to 2500 lbs, 2563 lbs with power adder, 2625 lbs with two power adders. · FP Honda throttle body inside diameters corrected across seven models: Civic 1.5 to 42", Civic Si to 55", CRX 1.5 to 42", CRX 84-87 to 33/42", CRX Si 88-91 to 55". · EP Mazda MX-5 1.8L (90-97) minimum weight cut to 2150 lbs; (94-97) variants to 2000, 2050, 2100 lbs. · EP Triumph GT6 dual 1.75-inch carburetors weight rises to 1940 lbs; triple Weber 40 DCOE option added at 1990 lbs. · EP Honda S2000 fuel injected throttle body inside diameter increases from 62mm to 64mm. · EP Triumph TR8 dry sump allowance moved from Carburetor line to Notes. · EP Porsche 944/924S 2.5L and 2.7L minimum weights corrected: 2479cc to 2306–2363 lbs, 2681cc to 2358–2415 lbs. · SRF rain/brake light must be Super Bright LEDs Inc. P/N PT-STRB-R24; secondary filament must connect to rain light switch. · SRF brake light must be Super Bright LEDs Inc. P/N PT-STRB-R24, with SCCA Enterprises P/N 180427A pigtail and strobing rain light kit. · SRF adds mandatory front brake ducts 12–36 inches, throttle pedal heel-toe extension, braided stainless flex lines, camber limit 5.0 degrees, radiator opening height 3½ ± ½ inches, rear shift cable clamp P/N WM302007A. · EP Porsche 944/924S combines 2.5L and 2.7L variants (83-89), raises weight to 2250–2415 lbs, allows 2681cc displacement. · FP Toyota Corolla 2TC loses 43 lbs to 1810; HP Corolla loses 50–52 lbs to 1910–2006. · EP Triumph GT6 minimum weight drops to 1800 lbs. · SRF radiator options expanded: Enterprises P/N 480465 with baffle 480464, 480466, or Automotive 1R698 and CU698 allowed if cross-reference equivalent. · AS crate motor part number specification clarified; both CT400 P/N-19370604 and 19370604 engine assemblies permitted for GM vehicles. · AS Ford Mustang GT 5.0L (15-17) Restricted maximum wheel diameter increases to 19.0 inches. · AS Dodge Challenger 5.7L/6.1L/6.4L V8 allows alternate front upper control arms; SPC-66045 spec part removed. · AS Dodge Challenger 5.7L/6.1L/6.4L V8 now allows alternate front brake calipers with adaptor brackets for component compatibility. · FP and HP Sprite and Spitfire 1500 intake valve size corrected to 36.6 mm, removing prior decimal specifications. · HP Volkswagen Rabbit Cabriolet 1780 removed; Rabbit 1588 and 1715 reclassified with year and body-type clarifications. · STU adds 2022 Toyota GR Cup and GR86 Cup, both 2387cc, 2700 lbs, 18-inch wheels, 245/620R18 slicks. · Ford Fiesta HP model years change to 11-19; Chevrolet Sonic FP model years change to 12-19. · SRF wet front tyre changes to Hoosier P/N 46100 P185/60R13 H20 or W2 with 2.5" ground clearance. · Toyota Celica 78-80 classified FP Prep level 2, 2100–2205 lbs, 2190 cc SOHC four-cylinder, stock carburetion, 11.0:1 compression limit, .450" valve lift limit. · SRF front W2 rain tyre Hoosier part number changes from 46100 to 46101 P185/65R13. · STU Mazda BP5A now classified at 1839 cc displacement, 2510 lbs minimum weight, alternate intake manifold permitted.showhide
  • AS Request to Classify 1970-1981 Camaro and Firebird in AS #33659cars addedaddedChevrolet Camaro, Pontiac Firebird 70–81 Full Prep classified in AS at 3400–3600 lbs with 108.0 wheelbase, specific head castings, and suspension modifications permitted.
  • AS Fuel Cell 12 #34194otheraddedAS class adds fuel cell location notes to multiple Cadillac, Chevrolet, Dodge and Ford models: cells within 24 inches of standard tank.
  • AS Please Classify the 6th Gen Into AS. #35448cars addedaddedChevrolet Camaro 6th gen Full Prep added to AS class at 3400 lbs base or 3600 lbs with built engine.
  • AS spec lines #35713otherunclearAS class: Ford Mustang GT 05-14 Restricted prep added; Cadillac CTS-V 04-07 to 3450 lbs; Camaro/Firebird variants reconfigured with weight and notes changes; Dodge Challenger 08-20 restrictor 76mm to 80mm; Ford Mustang variants updated wei…
  • FP GCR Correction - Redundant HP Spec Lines #35623removedremovedHP removes four redundant VW spec lines: Rabbit Cabriolet 1780, Scirocco 1588, Scirocco 1780 8-valve 83-88, Scirocco 1588.
  • FP Update FP Protege (01-03) Model Info #35715wordingwordingFP Mazda Protégé ES (01-03) renamed to Mazda Protégé ES/5 (01-03).
  • 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.
  • FP Update 1988-1991 Civic to Match 1988-1991 CRX #35399weightfaster · weightHP Honda Civic 1.5 1988-91 minimum weight drops 70 lbs to 2175; also 2-speed and 3-speed minimums cut 72 and 73 lbs.
  • 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.
  • FP FP data #35060weight +25 lbs
  • FP Request to Review Z3 2.5 Spec Line #35073weight +50 lbsslower · weightEP BMW Z3 2.5L minimum weight increased to 2500 lbs, 2563 lbs with power adder, 2625 lbs with two power adders.
  • FP Corrections to Honda Spec Lines in FP #35250wordingunclearFP Honda throttle body inside diameters corrected across seven models: Civic 1.5 to 42", Civic Si to 55", CRX 1.5 to 42", CRX 84-87 to 33/42", CRX Si 88-91 to 55".
  • FP Miata Alternate Head #35253weight -50 lbsfaster · weightEP Mazda MX-5 1.8L (90-97) minimum weight cut to 2150 lbs; (94-97) variants to 2000, 2050, 2100 lbs.
  • FP Triumph GT6 Adjustments #35255weightslower · weightEP Triumph GT6 dual 1.75-inch carburetors weight rises to 1940 lbs; triple Weber 40 DCOE option added at 1990 lbs.
  • FP Honda S2000 throttle body #35272inductionfaster · inductionEP Honda S2000 fuel injected throttle body inside diameter increases from 62mm to 64mm.
  • FP Correction within Triumph TR8 Spec Line #35315wordingwordingEP Triumph TR8 dry sump allowance moved from Carburetor line to Notes.
  • FP Correction to EP 924S/944 Spec Line #35317weightweightEP Porsche 944/924S 2.5L and 2.7L minimum weights corrected: 2479cc to 2306–2363 lbs, 2681cc to 2358–2415 lbs.
  • SRF Update SRF Rain / Brake Rule #34706otherotherSRF rain/brake light must be Super Bright LEDs Inc. P/N PT-STRB-R24; secondary filament must connect to rain light switch.
  • SRF Update SRF Brake Light Rule v1 #34853otherotherSRF brake light must be Super Bright LEDs Inc. P/N PT-STRB-R24, with SCCA Enterprises P/N 180427A pigtail and strobing rain light kit.
  • SRF SRF / SRF3 Rule Updates #35268suspension & brakessuspension & brakesSRF adds mandatory front brake ducts 12–36 inches, throttle pedal heel-toe extension, braided stainless flex lines, camber limit 5.0 degrees, radiator opening height 3½ ± ½ inches, rear shift cable clamp P/N WM302007A.
  • FP Porsche 944/924S Rule Change Request #35002weightslower · weightEP Porsche 944/924S combines 2.5L and 2.7L variants (83-89), raises weight to 2250–2415 lbs, allows 2681cc displacement.
  • FP FP and HP Toyota Corolla #35030weight -43 lbsfaster · weightFP Toyota Corolla 2TC loses 43 lbs to 1810; HP Corolla loses 50–52 lbs to 1910–2006.
  • FP Triumph GT6 Adjustments #35054weight -30 lbsfaster · weightEP Triumph GT6 minimum weight drops to 1800 lbs.
  • SRF SRF Radiator Rule Update #34805otheraddedSRF radiator options expanded: Enterprises P/N 480465 with baffle 480464, 480466, or Automotive 1R698 and CU698 allowed if cross-reference equivalent.
  • AS Crate Motor Part Numbers #32944wordingwordingAS crate motor part number specification clarified; both CT400 P/N-19370604 and 19370604 engine assemblies permitted for GM vehicles.
  • AS Request wheel size change #33007tyres & wheelsfaster · tyres & wheelsAS Ford Mustang GT 5.0L (15-17) Restricted maximum wheel diameter increases to 19.0 inches.
  • AS Alternative Upper Front Control Arms for Dodge Challenger #33352wordingwordingAS Dodge Challenger 5.7L/6.1L/6.4L V8 allows alternate front upper control arms; SPC-66045 spec part removed.
  • AS Front Brake Caliper Adapters for Dodge Challenger #33353otherotherAS Dodge Challenger 5.7L/6.1L/6.4L V8 now allows alternate front brake calipers with adaptor brackets for component compatibility.
  • FP Correct Intake Valve Size on 1500cc Midget/Spitfire #34419wordingwordingFP and HP Sprite and Spitfire 1500 intake valve size corrected to 36.6 mm, removing prior decimal specifications.
  • FP ITC to FP? #34286cars addedremoved · cars addedHP Volkswagen Rabbit Cabriolet 1780 removed; Rabbit 1588 and 1715 reclassified with year and body-type clarifications.
  • 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.
  • FP Request to Classify Sonic and Fiesta in HP #34264cars addedaddedFord Fiesta HP model years change to 11-19; Chevrolet Sonic FP model years change to 12-19.
  • SRF Hoosier SRF Wet Front Tire Rule Update #34189tyres & wheelstyres & wheelsSRF wet front tyre changes to Hoosier P/N 46100 P185/60R13 H20 or W2 with 2.5" ground clearance.
  • FP Classification Request for 1978 Toyota Celica #34097cars addedaddedToyota Celica 78-80 classified FP Prep level 2, 2100–2205 lbs, 2190 cc SOHC four-cylinder, stock carburetion, 11.0:1 compression limit, .450" valve lift limit.
  • SRF Update SRF Front W2 Rain Tire Part Number #34118tyres & wheelstyres & wheelsSRF front W2 rain tyre Hoosier part number changes from 46100 to 46101 P185/65R13.
  • STU Alternate OEM Miata Intake Manifold #33827engineadded · engineSTU Mazda BP5A now classified at 1839 cc displacement, 2510 lbs minimum weight, alternate intake manifold permitted.
Super Tour Mar 2023 ST23MAR102023-03-101:35.710Anthony Geraci · fastest of 14 · top 5 within 3.7s+0.724s (+0.76%)1:35.081Anthony Geraci · fastest of 14 · top 5 within 2.9s+1.000s (+1.06%)135.4David Brand-6.2 mph (-4.4%)1:38.342Mason Workman · fastest of 6 · top 5 within 8.5s-1.122s (-1.13%)1:38.568Mason Workman · fastest of 6 · top 5 within 5.9s+0.177s (+0.18%)122.6Mason Workman-3.9 mph (-3.1%)
34 rule changes (AS: 3, SRF: 3, STU: 14, FP: 14)8 weight · 6 cars added · 4 engine · 2 aero · 2 tyres & wheels · 1 induction · 10 wording · 1 other · SRF removes 1985 Renault Alliance solid front rotor option; restrictor sizes decrease 1mm for newer Kawasaki and multi-brand engines; minimum weights increase to 1100 lbs. · STU minimum weights adjusted: 2450 cc to 2595 lbs, 2600 cc to 2710 lbs. · FP Mazda Protégé ES (01-03) renamed to Protégé ES/5 (01-03) to include P5 model variant. · EP, FP, HP port matching limited to 1 inch depth from mating surface. · AS adds Hoosier W2 wet tyre option alongside R7, R6, WET/H20. · AS Dodge Challenger 08-20 gains two transmission ratio options: 2.97–0.50 or 2.26–0.63. · Volkswagen New Beetle 2.5L 5-cyl DOHC classified in EP at 2400–2520 lbs with fuel injection. · EP Mazda RX-7 12A/13B and 13B now permit 2 bbl fuel injected throttle body with 42mm chokes on dual-y manifold. · EP VW Corrado 92-95 stroke corrected to 90.3 mm and displacement to 2792 cc. · 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. · AS Cadillac CTS-V 6.0L V8 Restricted Prep removes 295 tire size 50 lb penalty. · 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. · EP Subaru BRZ title updated to include model years 13–20; Toyota 86/Scion FR-S title likewise updated to 13–20. · SRF tire rule wording clarified: tires must be run as delivered. · SRF brake rotor minimum thickness reduced from 13.25 mm to 12.20 mm; seals and air filter specs clarified. · FP Lotus Super Seven 91.7 ci minimum weight increases 50 lbs, to 1580. · EP Mazda MX-5 Global Cup 16-22 minimum weight set to 2400 lbs; sequential gearbox allowed with 150 lbs penalty. · BMW 128i (08-13) classified in EP at 2700 lbs minimum with 2996 cc engine, stock throttle body, 11.0:1 compression and 0.400" valve lift limits. · EP, FP, HP open cars now allow carbon fiber hardtops if they retain OEM exterior profiles. · Mazda Protégé ES 99-00 classified FP, 2150–2258 lbs, 1839 cc DOHC, fuel injection, 11.0:1 compression, 0.450" valve lift. · 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. · EP Mazda RX-8 13B carburetor option replaced with fuel-injected throttle body or stock fuel injection. · EP, FP, HP Production clarify idle control valve options: stock original allowed, removable with blocked ports, or mechanical replaced with electronic stock type. · FP BMW 325e/es displacement corrected to 2693 cc. · 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.showhide
  • SRF Update SRF Brake Rule #33469enginefaster · engineSRF removes 1985 Renault Alliance solid front rotor option; restrictor sizes decrease 1mm for newer Kawasaki and multi-brand engines; minimum weights increase to 1100 lbs.
  • STU E&O STU NA Weight Chart. #33737weightfaster · weightSTU minimum weights adjusted: 2450 cc to 2595 lbs, 2600 cc to 2710 lbs.
  • FP Request to Add Mazda Protege P5 to FP #33664cars addedaddedFP Mazda Protégé ES (01-03) renamed to Protégé ES/5 (01-03) to include P5 model variant.
  • FP Review Limited Prep Port Matching Rules #33600wordingwordingEP, FP, HP port matching limited to 1 inch depth from mating surface.
  • AS Request to add Hoosier W2 #33031tyres & wheelsadded · tyres & wheelsAS adds Hoosier W2 wet tyre option alongside R7, R6, WET/H20.
  • AS correction of Dodge Challenger specification line #33151cars addedaddedAS Dodge Challenger 08-20 gains two transmission ratio options: 2.97–0.50 or 2.26–0.63.
  • FP Request to classify VW New Beetle 2.5L in EP #32725cars addedaddedVolkswagen New Beetle 2.5L 5-cyl DOHC classified in EP at 2400–2520 lbs with fuel injection.
  • FP Request Rotary Injection on Dual Y manifold #32775inductionadded · inductionEP Mazda RX-7 12A/13B and 13B now permit 2 bbl fuel injected throttle body with 42mm chokes on dual-y manifold.
  • FP Request for Corrado Stroke & Displacement Correction #32985wordingwordingEP VW Corrado 92-95 stroke corrected to 90.3 mm and displacement to 2792 cc.
  • 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.
  • AS Request CTS-V Spec Line Error Correction #30242weightfaster · weightAS Cadillac CTS-V 6.0L V8 Restricted Prep removes 295 tire size 50 lb penalty.
  • 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.
  • FP Subaru BRZ Model Years #32500wordingwordingEP Subaru BRZ title updated to include model years 13–20; Toyota 86/Scion FR-S title likewise updated to 13–20.
  • SRF SRF Tire Rule Update #32614wordingwordingSRF tire rule wording clarified: tires must be run as delivered.
  • SRF Brake, seal, and air filter clarifications #32670otherfasterSRF brake rotor minimum thickness reduced from 13.25 mm to 12.20 mm; seals and air filter specs clarified.
  • FP Weight Adjustment of Lotus 7 #32213weight +50 lbsslower · weightFP Lotus Super Seven 91.7 ci minimum weight increases 50 lbs, to 1580.
  • FP EP MX-5 Global Cup Car #32218weightweightEP Mazda MX-5 Global Cup 16-22 minimum weight set to 2400 lbs; sequential gearbox allowed with 150 lbs penalty.
  • FP Please Class BMW 128i in EP #32370cars addedaddedBMW 128i (08-13) classified in EP at 2700 lbs minimum with 2996 cc engine, stock throttle body, 11.0:1 compression and 0.400" valve lift limits.
  • FP Inconsistency in Body Work Descriptions #32396aeroadded · aeroEP, FP, HP open cars now allow carbon fiber hardtops if they retain OEM exterior profiles.
  • FP Request to classify the 1999-2000 Mazda Protege in FP #32398cars addedaddedMazda Protégé ES 99-00 classified FP, 2150–2258 lbs, 1839 cc DOHC, fuel injection, 11.0:1 compression, 0.450" valve lift.
  • 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.
  • FP Mazda RX8 with 13b Rotary #32170engineengineEP Mazda RX-8 13B carburetor option replaced with fuel-injected throttle body or stock fuel injection.
  • FP Request Idle control valve clarification #32178wordingwordingEP, FP, HP Production clarify idle control valve options: stock original allowed, removable with blocked ports, or mechanical replaced with electronic stock type.
  • FP Correct FP BMW 325e/es Displacement #32394wordingunclearFP BMW 325e/es displacement corrected to 2693 cc.
  • 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.
Super Tour Mar 2022 ST22MAR122022-03-121:36.346Gregory Eaton · fastest of 3 · top 3 within 7.0s+2.115s (+2.24%)1:35.993Gregory Eaton · fastest of 2+1.259s (+1.33%)143.6Gregory Eaton-19.3 mph (-11.9%)1:34.986Johan Schwartz · fastest of 9 · top 5 within 6.2s-1.596s (-1.65%)1:34.081Johan Schwartz · fastest of 9 · top 5 within 6.7s-2.622s (-2.71%)141.5Johan Schwartz+5.9 mph (+4.4%)-1.912squal -1.360s98.0%qual 98.6%1:39.464Perry Simonds · fastest of 5 · top 5 within 220.2s+0.546s (+0.55%)1:38.391Perry Simonds · fastest of 5 · top 5 within 16.9s+1.167s (+1.20%)126.5Ken Kannard+3.6 mph (+2.9%)+2.398squal +3.118s102.5%qual 103.2%
55 rule changes (AS: 11, SRF: 5, STU: 13, FP: 26)11 cars added · 11 engine · 9 weight · 3 tyres & wheels · 2 induction · 1 aero · 1 suspension & brakes · 13 wording · 4 other · EP BMW Z3 2.5L intake restrictor reduced from 59mm to 58mm flat plate. · Ford Mustang 94-98 weight reduced to 2550/2614/2678 lbs; 99-03 3.8L classified EP at 2700/2768/2835 lbs. · EP, FP, HP Improved Touring cars may use any DOT-approved tyre as defined by 9.3.45. · FP VW Golf III/Jetta III 93-98 intake valve shrinks to 39.5 mm (1.56 in), exhaust to 32.9 mm (1.30 in). · 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. · EP, FP, HP: stock/original idle control devices permitted unmodified or completely removed with openings blocked. · 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. · SMG Long Tube Headers: Borla PN 17237 discontinued, approved alternatives American Racing MT3-05134300LSNC or Kooks PN 11312000. · AS Mercury Capri 79-86 removed as separate spec line, merged into Ford Mustang 79-93 spec line. · AS Spec Mustang SMG Restricted Prep removes 3.73 gear ratio and 355/300 brake disc sizes. · AS Camaro, Firebird, Mustang full prep engines: alternate GM and Ford Performance cylinder heads permitted regionally with Allstar restrictor ALL26180. · EP Porsche 968 intake valve size changes to 39.0 mm, 1.54 mm seat width. · EP, FP, HP front-wheel-drive cars may alter body and subframes to install alternate axle shaft, matching RWD freedom. · EP BMW Z3 2.5L adds alternate throttle body option with Turner adapter and permits head casting 1738400. · FP Honda Civic Del Sol VTEC compression ratio limited to 11.0:1, valve lift to .425", removes dry sump and internal engine prep allowances. · FP Honda Prelude 84-87 and Mazda GLC/323 86-88 valve lift measurement method clarified, Level 1 parts list removed. · 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. · EP Porsche 944S2 89-91 requires 56mm flat plate intake restrictor; compression ratio 12.0:1 max, valve lift 0.500" max, dry sump allowed. · Toyota Corolla GTS RWD (84-87) and FX16 FWD (87-88) added to HP; old Corolla (84-87) removed. · SRF wet tyres front P185/65R13 W2 option added; air box clarified as-delivered; SRF3 restrictor plate G301048 mandatory Jan 1 2022; P2 motorcycle engines up to 1005cc with 35mm restrictor, 2009+ stock 1075 lbs, 2008 stock 1025 lbs, modifie… · AS Chevrolet/Pontiac Camaro & Firebird 93-02 gains BMR AA004 or UMI 2310 adjustable front upper control arms. · AS Pontiac GTO 04-06 Restricted Prep minimum weight rises: LS1 to 3300 lbs, LS2 to 3350 lbs on 295 tires. · Toyota MR-2 1.6L 85-89 HP track width corrected to 15×47 / 15×47 inches; stock track baseline now 103% plus 2.5 inches. · EP Honda S2000 now allows F22c engine in 1997cc and 2157cc displacements with revised weight brackets and specifications. · EP Nissan 240-SX S13/S14 weight drops to 2400 lbs base, 2460 turbo, 2520 supercharged; comp ratio raised to 12.0:1, valve lift to 0.500 inch. · SRF wet tyres add Hoosier W2 option alongside existing H20 from October 4, 2021. · SRF adds SADEV-SRF3 6-speed sequential transmission option with ratios 3.0–0.92:1 and 3.20 final drive. · SRF seal requirements clarified: seals now must be on driveline components in designated locations; unsealed components removed and inspected by CSR or Enterprises rather than engine shipped for testing. · EP Lotus/Caterham 7 America fuel injection permitted; IT preparation engine limitation removed. · Plymouth Arrow 76–80 classified in HP Prep at 1800–1890 lbs with 1598 cc iron-block OHV four-cylinder. · BMW 318i/is E30 (84-85) reclassified from FP to HP at 2200–2310 lbs, SOHC 1797cc, fuel injection, 11.0:1 compression, .425" valve lift limit. · FP Fiat X1/9 1300 loses 50 lbs to 1665; X1/9 Bertone loses 50 lbs to 1765. · Daimler SP 250 classified in EP with 2165 lbs minimum weight, 2548 cc eight-cylinder OHV engine, SU or Stromberg carburetors. · 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. · AS Cadillac CTS-V 6.0L LS6 removes 295-tire 50 lb penalty. · AS consolidates seven SN95 Mustang '94-'04 spec lines into three unified lines by model year and engine. · AS Camaro/Firebird LT1 and LS1 transmission changed to TUET1 6362; Mustang GT 4.6L/5spd to TUKT16901, loses 300 lbs. · AS Camaro & Firebird and Mustang GT gear ratio specifications restored with alternate sets permitted. · AS Camaro, Firebird, Mustang, and Capri all gain 50 lbs minimum weight across seven model year variants. · Porsche 924 Level 1 Prep moved from EP to FP classification. · EP, FP, HP clarify percentage weight penalties sum before applying to base weight, round to nearest pound. · SRF3 alternator pulley specified as P/N G902130 or G902130A, minimum 12oz. · 84-87 Mazda 626 reclassified from FP to HP with 2300–2415 lb weight, 1998cc SOHC engine, two 32mm carburetors. · FP Fiat X1/9 and Bertone 1300 brake rotors now 257 x 12 mm, 10.1 inch diameter, 0.407 inch thickness. · STU fender flare rules clarified: maximum 2 inches total, must cover tire contact patch from above, cannot alter body configuration or wheel opening geometry. · Mazda 3 S 04-08 classified in EP at 2350 lbs minimum, 2.26L DOHC four-cylinder, fuel injected with 55mm throttle body, comp ratio 12.0:1 max, valve lift 0.500" max. · FP Volkswagen Golf and Jetta III and IV intake valves increase to 40.0 mm, exhaust to 33.0 mm. · 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.showhide
  • FP EP Adjustments #31858inductionslower · inductionEP BMW Z3 2.5L intake restrictor reduced from 59mm to 58mm flat plate.
  • FP 1999 3.8L Ford Mustang to EP? #31635weightfaster · weightFord Mustang 94-98 weight reduced to 2550/2614/2678 lbs; 99-03 3.8L classified EP at 2700/2768/2835 lbs.
  • FP Improved Touring Tires #32064tyres & wheelsadded · tyres & wheelsEP, FP, HP Improved Touring cars may use any DOT-approved tyre as defined by 9.3.45.
  • FP VW Golf Jetta 2.0L intake and exhaust size correction. #32173engineslower · engineFP VW Golf III/Jetta III 93-98 intake valve shrinks to 39.5 mm (1.56 in), exhaust to 32.9 mm (1.30 in).
  • 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.
  • FP Throttle Body and Idle Air #31800wordingwordingEP, FP, HP: stock/original idle control devices permitted unmodified or completely removed with openings blocked.
  • 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.
  • AS Proposed Revisions to SCCA GCR 2021 Appendix M, Part 3 #30295wordingwordingSMG Long Tube Headers: Borla PN 17237 discontinued, approved alternatives American Racing MT3-05134300LSNC or Kooks PN 11312000.
  • AS specification line consolidation and correction #31846cars addedremoved · cars addedAS Mercury Capri 79-86 removed as separate spec line, merged into Ford Mustang 79-93 spec line.
  • AS correction of SMG specification line #31847wordingremovedAS Spec Mustang SMG Restricted Prep removes 3.73 gear ratio and 355/300 brake disc sizes.
  • AS Alternate cylinder heads for full prep engine builds - Evaluation #31851engineadded · engineAS Camaro, Firebird, Mustang full prep engines: alternate GM and Ford Performance cylinder heads permitted regionally with Allstar restrictor ALL26180.
  • FP Porsche 968 Engine Questions #31478engineengineEP Porsche 968 intake valve size changes to 39.0 mm, 1.54 mm seat width.
  • FP PCS E. 2. n. 4. Add Axle Shaft to Allow FWD the Same Freedom #31592otheraddedEP, FP, HP front-wheel-drive cars may alter body and subframes to install alternate axle shaft, matching RWD freedom.
  • FP BMW Z3 2.5L Spec Line #31724engineadded · engineEP BMW Z3 2.5L adds alternate throttle body option with Turner adapter and permits head casting 1738400.
  • FP FP Del Sol VTEC #31859engineslower · engineFP Honda Civic Del Sol VTEC compression ratio limited to 11.0:1, valve lift to .425", removes dry sump and internal engine prep allowances.
  • FP Standardize Level 2 Classifications in FP #31868wordingwordingFP Honda Prelude 84-87 and Mazda GLC/323 86-88 valve lift measurement method clarified, Level 1 parts list removed.
  • 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.
  • FP 944S2 Restrictor #31396inductionslower · inductionEP Porsche 944S2 89-91 requires 56mm flat plate intake restrictor; compression ratio 12.0:1 max, valve lift 0.500" max, dry sump allowed.
  • FP Classing Clarification for 1986 Toyota Corolla FX16 #31527cars addedaddedToyota Corolla GTS RWD (84-87) and FX16 FWD (87-88) added to HP; old Corolla (84-87) removed.
  • SRF Three Updates to SRF Rules #31523otherotherSRF wet tyres front P185/65R13 W2 option added; air box clarified as-delivered; SRF3 restrictor plate G301048 mandatory Jan 1 2022; P2 motorcycle engines up to 1005cc with 35mm restrictor, 2009+ stock 1075 lbs, 2008 stock 1025 lbs, modifie…
  • AS Request for adjustable Front Upper Control Arms on 4th Gen F-Body #30457otheraddedAS Chevrolet/Pontiac Camaro & Firebird 93-02 gains BMR AA004 or UMI 2310 adjustable front upper control arms.
  • AS Request Pontiac GTO tire size change #30881weightslower · weightAS Pontiac GTO 04-06 Restricted Prep minimum weight rises: LS1 to 3300 lbs, LS2 to 3350 lbs on 295 tires.
  • FP E&O; MR2 Track #31120suspension & brakessuspension & brakesToyota MR-2 1.6L 85-89 HP track width corrected to 15×47 / 15×47 inches; stock track baseline now 103% plus 2.5 inches.
  • FP Request to Allow F22c Engine for 2000-2003 Honda S2000 #30548cars addedaddedEP Honda S2000 now allows F22c engine in 1997cc and 2157cc displacements with revised weight brackets and specifications.
  • FP Request a review of the S14 240SX in EP. #30873weight -200 lbsfaster · weightEP Nissan 240-SX S13/S14 weight drops to 2400 lbs base, 2460 turbo, 2520 supercharged; comp ratio raised to 12.0:1, valve lift to 0.500 inch.
  • SRF SRF Wet Tires #30849tyres & wheelsadded · tyres & wheelsSRF wet tyres add Hoosier W2 option alongside existing H20 from October 4, 2021.
  • SRF SADEV-SRF3 Transmission #30926cars addedaddedSRF adds SADEV-SRF3 6-speed sequential transmission option with ratios 3.0–0.92:1 and 3.20 final drive.
  • SRF SRF Update Maintenance, Repairs and Seals #30961wordingwordingSRF seal requirements clarified: seals now must be on driveline components in designated locations; unsealed components removed and inspected by CSR or Enterprises rather than engine shipped for testing.
  • FP Lotus/Caterham 7 America Request #30392wordingwordingEP Lotus/Caterham 7 America fuel injection permitted; IT preparation engine limitation removed.
  • FP Request to classify ITC Plymouth Arrow #30588cars addedaddedPlymouth Arrow 76–80 classified in HP Prep at 1800–1890 lbs with 1598 cc iron-block OHV four-cylinder.
  • FP Reclassification of the 1984/85 BMW 318i from FP to HP #30661cars addedaddedBMW 318i/is E30 (84-85) reclassified from FP to HP at 2200–2310 lbs, SOHC 1797cc, fuel injection, 11.0:1 compression, .425" valve lift limit.
  • FP Fiat x1/9 Competition Adjustments #30711weight -50 lbsfaster · weightFP Fiat X1/9 1300 loses 50 lbs to 1665; X1/9 Bertone loses 50 lbs to 1765.
  • FP Reclassify Daimler SP 250 #30721cars addedaddedDaimler SP 250 classified in EP with 2165 lbs minimum weight, 2548 cc eight-cylinder OHV engine, SU or Stromberg carburetors.
  • 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.
  • AS Request CTS-V Spec Line Error Correction #30242weightfaster · weightAS Cadillac CTS-V 6.0L LS6 removes 295-tire 50 lb penalty.
  • AS Request to consolidate SN95 Mustang '94-'04 Mustang spec lines #30428wordingwordingAS consolidates seven SN95 Mustang '94-'04 spec lines into three unified lines by model year and engine.
  • AS American Sedan Transmission Rule Change Request #30595enginefaster · engineAS Camaro/Firebird LT1 and LS1 transmission changed to TUET1 6362; Mustang GT 4.6L/5spd to TUKT16901, loses 300 lbs.
  • AS Correction to specifications inadvertently deleted #30691wordingwordingAS Camaro & Firebird and Mustang GT gear ratio specifications restored with alternate sets permitted.
  • AS weight adjustments #30700weight +50 lbsslower · weightAS Camaro, Firebird, Mustang, and Capri all gain 50 lbs minimum weight across seven model year variants.
  • FP Move Porsche 924 in Level 1 Prep From EP to FP #30135cars addedaddedPorsche 924 Level 1 Prep moved from EP to FP classification.
  • FP Clarify Application of Percentage Based Weight Penalties #30669wordingwordingEP, FP, HP clarify percentage weight penalties sum before applying to base weight, round to nearest pound.
  • SRF SRF3 Alternator Pulley #30684engineadded · engineSRF3 alternator pulley specified as P/N G902130 or G902130A, minimum 12oz.
  • FP Change Classification of 84-87 Mazda 626 from FP to HP #30350cars addedadded84-87 Mazda 626 reclassified from FP to HP with 2300–2415 lb weight, 1998cc SOHC engine, two 32mm carburetors.
  • FP Fiat X1/9 brake rotors #30423otherotherFP Fiat X1/9 and Bertone 1300 brake rotors now 257 x 12 mm, 10.1 inch diameter, 0.407 inch thickness.
  • 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.
  • FP Please Classify Mazda3 in FP #30165cars addedaddedMazda 3 S 04-08 classified in EP at 2350 lbs minimum, 2.26L DOHC four-cylinder, fuel injected with 55mm throttle body, comp ratio 12.0:1 max, valve lift 0.500" max.
  • FP Golf MkIII Valve Size Request #30268enginefaster · engineFP Volkswagen Golf and Jetta III and IV intake valves increase to 40.0 mm, exhaust to 33.0 mm.
  • 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.
Super Tour Mar 2021 ST21MAR192021-03-191:34.231Tom Ellis · fastest of 7 · top 5 within 7.4s1:34.734Tom Ellis · fastest of 8 · top 5 within 5.6s163.0Tom Ellis1:36.582David Brand · fastest of 10 · top 5 within 6.9s1:36.703David Brand · fastest of 8 · top 5 within 5.5s135.6David Brand+1.969squal +2.351s102.1%qual 102.5%1:38.918Michael Kamalian · fastest of 8 · top 5 within 7.0s1:37.224Michael Kamalian · fastest of 9 · top 5 within 8.3s122.9Ken Kannard+2.490squal +4.687s102.6%qual 105.0%
119 earlier rule changes on record, in force before Super Tour Mar 2021 (from 2019)28 cars added · 14 engine · 13 weight · 8 aero · 6 induction · 2 suspension & brakes · 1 tyres & wheels · 37 wording · 10 other · AS Mustang 4.6L 5spd gains cold air intake freedom; 5.0L 6spd now requires 56mm flat plate restrictor. · AS CTS-V 5.7L LS6 and 6.0L LS2 may use Driveshaft Shop P/N GMCTSV2-C carbon fiber driveshaft. · AS Chevrolet Camaro SS V8 6.2L Restricted Prep model years extended from 10–13 to 10–15. · SRF and SRF3 mandatory identification revised: removed Ford Performance and Blue Oval decals, added Hoosier logo placement. · 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. · AS Ford Mustang GT 5.0L 15-17 Restricted added to Spec Line with 3600 lbs minimum weight, 55mm restrictor, 18×10 wheels, 295 tires. · AS underhood bracing on stock hoods, trunks, and rear decks may be modified or removed. · AS Cadillac CTS-V 04-07 with 295 tire drops to 3450 lbs; Camaro SS V8 10-13 and Challenger 08-20 specs removed. · AS Camaro & Firebird (93-02) and Mustang GT (05-14) specifications restored with weight minimums 3250–3500 and 3350–3600 lbs respectively. · EP Austin-Healey 3000 gains option to use TR-6 front calipers and discs as alternate. · FP Volkswagen Golf 1.8, Jetta, Rabbit and Scirocco gain 50 lb weight breaks, minimum weights to 1900–1733 lbs. · STU Mazda 13B Spec and Bridge Port removed; Street Port added at 2400 lbs minimum weight. · AS Dodge Challenger gains 6.1L and 6.4L V8 options; 5.7L weight rises to 3500 lbs on 295 tyres, 3600 on 315 tyres; compression to 10.9:1 max. · AS Camaro & Firebird (93-02) and Ford Mustang Coupe GT (05-14) spec lines consolidated; Camaro/Firebird now allows both LT1 and LS1 engines; Mustang now allows both 4.6L 3-valve and 5.0L 4-valve engines with restrictor. · FP Mk2 Golf and Jetta 1.8 lose 50 lbs to 1900; HP Jetta GLI engine code removed. · EP, FP, HP Level 1 and Level 2 induction systems: carburettor jets, needles, metering rods allowed; throttle body porting permitted; wording clarified. · EP Nissan Datsun SRL 311U Roadster minimum weight reduced 75 lbs to 1925. · EP Triumph TR8 78-81 minimum weight drops to 2500 lbs. · Honda Civic EX 96-00 classified FP2 at 1975 lbs, SOHC 1590cc, fuel injection, 56mm throttle body, comp ratio 12.0:1 max, valve lift 0.450" max. · FP adds FAJS to permitted Weber-type and auto-type carburetor substitutes in two sections. · SRF rear springs limited to P/N 280390 only, previous part numbers no longer allowed; ground clearance wording clarified. · ST aero devices and reference areas must include end plates, exclude fasteners under 1/2" protrusion. · HP 84-87 Toyota Corolla wheel diameter increases from 13 to 15 inches. · STU fender flare rule reworded: now per-corner up to 2" total, 1% weight penalty applies to entire modification. · AS Dodge Challenger 5.7L V8 now requires iron block instead of aluminum, compression to 10.5:1 max, intake valve 12.7 mm, exhaust 12.3 mm, intake timing 188 degrees, exhaust timing 205 degrees. · AS Dodge Challenger 08-14 rear spoiler: 1GL20RXF replaced with 1GL20TZZAB; 82211606 still permitted. · EP BMW Z3 2.5L cylinder head casting 1738400 permitted with iron block castings 1748933 or 1738566. · 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. · AS class pursuing specified list of eligible tires; list details unclear from text provided. · AS class tire eligibility list under development; no specifications changed yet. · AS Coyote Mustang restrictor plate under review for 2021; no change effective yet. · AS Restricted Prep 4.6 3V now permits conversion to 2 valve configuration. · AS Ford Mustang Coupe GT 4.6L 3V Restricted Prep now permits Ford Performance camshaft kit P/N M-6550-3V. · 2010-2014 Camaro remains classified in AS; no specification changes. · AS class cylinder head supplier discontinuation; replacement option pending for 2021 season. · AS Mustang, Capri, Camaro, and Firebird maximum brake rotor diameter increased from 12.2 to 13.1 inches. · unclear · Porsche 911 S 67-68 classified in EP at 1800–1890 lbs, 1991cc opposed 6-cylinder SOHC with 36mm carburetors. · FP Mazda 626 84-87 carburetor spec clarified to two auto-type sidedraft 32mm choke or fuel injection. · 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. · EP BMW 2.8L, 328i E36/E46, and 325i E36 now require iron blocks only; 325i E46 aluminum block removed. · FP Volkswagen Scirocco E&O adds four engine variants with weights 1520–1853 lbs and displacements 1471–1780 cc. · STU Mazda 13B Bridge Port and Street Port added with 2550 lbs and 2250 lbs minimum weight respectively. · FP Pre: 1990–1994 Mazda Protégé classified at 2150–2258 lbs, 1839cc DOHC, fuel injection, 11.0:1 compression, .450" valve lift limit. · HP Mini Cooper 02-06 and 07-13 convertible model years corrected to 05-08 and 09-15 respectively. · SRF Penske shock P/N 280396 bump stop P/N 280407 becomes mandatory, maximum one per shock, effective 05/01/2020. · EP Caterham 7 America engine limited to IT prep with specific sections, comp ratio 10.0:1, valve lift .380 inch. · 1989-90 Nissan 240-SX SOHC added to FP Pre L2 at 2400–2520 lbs, 2389 cc, fuel injection, 11.0:1 compression, .450" valve lift limit. · 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. · FP Volkswagen Jetta, Rabbit, Scirocco reclassified with weights 1520–1853 lbs, intake valves 40.0 mm, exhaust 33.0 mm, throttle 35/52 mm. · HP Datsun 510 allows 40 DCOE carburetor option alongside existing 40 DCNF and 36mm DCNVH; auto side drafts moved to penalty structure. · Porsche 914-4 2.0L classified in FP Prep 2 at 2030–2132 lbs with 1968cc OHV engine, Solex/Weber/Dellorto carbs or fuel injection, 11.0:1 compression limit, .450" valve lift limit. · FP Ford Fiesta 78-80 minimum weight reduced 130 lbs, to 1660. · 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. · AS rear trailing arms may be replaced with tubular arms maintaining stock length and axle location purpose only. · AS Ford and GM full prep cars get increased weight reduction from 150 to 200 lbs. · 05-10 Ford Mustang Coupe GT 4.6L OHC classified AS with 3200 lbs minimum weight, HR cam permitted. · 10-15 Camaro Full Prep classified AS with 3400 lbs base weight, 3700 lbs over 313 CID, specific head castings and Edelbrock heads permitted. · HP Datsun 1200 carburetor option changes from 26mm to 30mm choke(s) in 40 DCN, DCNF, IDF. · Mazda Miata models EP and FP throttle body specified 55mm, brake rotor thickness figures removed. · FP Mazda Protégé ES 2001–2003 newly classified at 2350–2468 lbs with 1991 cc DOHC four-cylinder, fuel injection, 11.0:1 compression, .450 in. valve lift limit. · SRF rain and brake rule supersedes GCR 9.3.32.B.2 effective 1/1/2024 through 12/31/2024. · FP and HP: 1988–91 Honda Civic and CRX track widths corrected to 61.3 / 61.7 inches across multiple levels. · EP, FP, HP cylinder head rules reorganized for clarity; no performance change. · SRF adds tire warmer prohibition and specifies Hoosier dry and wet tire part numbers. · SRF front nose weight minimum reduced from 35 to 32 lbs. · SRF2 becomes Regional Only; SRF3 nomenclature changed from GEN3 to Ford 1.6L conversion; SRF and SRF3 no longer compete together for points. · STU allows OEM electronic throttle bodies, manual conversion, cam changes, and manual-to-electronic conversion with same inner diameter. · AS Spec Mustang (SMG) added as Restricted Prep class. · FP and HP Austin-Healey Sprite Mk I / MG Midget may replace rear bodywork aft of cockpit with alternate material stock-appearing components. · EP Mazda MX-5 Global Cup classification updated to include 2019 model year. · Production classes: suspension rule clarified to specify spindles, hubs, bushings, bearings, and ball joints unrestricted. · Production carburetor and fuel injection rules clarified: permitted optional carburetors listed, Weber and auto-type substitutions specified, fuel injection throttle body and butterfly dimensions detailed, intake manifold port extension pr… · EP, FP, HP carburetors: jets, needles, metering rods, needle valves unrestricted; choke parts removable; stock or optional Weber 40 DCN permitted; Weber types, auto types listed. · STU wing assembly wording corrected: no part may be higher than roof height. · AS class ride height minimum clarified: five inches measured at rocker panel, excluding seams and stock effects. · EP Mazda MX-5/Miata model years expand from 1999-2002 to 1999-2005. · SRF drivers may now use Dash Windscreen Kit P/N 1180103 or P/N 180102. · 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. · AS Ford Mustang 79-93 non-Cobra drops 100 lbs to 3150; over 313 CID Cobra drops 100 lbs to 3450. · 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. · EP, FP, HP: clarified that tapered holes in ball joints can be reamed for bolt conversion, and wheel bearings and hubs unrestricted on all axles. · EP open cars may now use aftermarket hardtops if OEM-appearance and non-carbon-fiber; specific model allowances removed as redundant. · 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. · FP Dodge Daytona/Chrysler Laser 84-85 added at 2100 lbs; Shelby Charger/Omni 024 83-84 weight cut to 2100 lbs. · 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. · AS adds Spec Mustang SMG classification with 107.1 wheelbase, 3.73 gears, 355mm front and 300mm rear brakes. · STU adds Honda K20C1 Turbo I4, 1996 cc, 3025 lbs minimum weight, 36mm TIR required.showhide
  • AS AS Mustang LP 4.6 3V Classification Transmission Request #29886enginefaster · engineAS Mustang 4.6L 5spd gains cold air intake freedom; 5.0L 6spd now requires 56mm flat plate restrictor.
  • AS Request CF driveshaft on CTS-V for durability improvement #30117otheraddedAS CTS-V 5.7L LS6 and 6.0L LS2 may use Driveshaft Shop P/N GMCTSV2-C carbon fiber driveshaft.
  • AS Adjustment to model years of 5th generation RP Camaro #30348cars addedaddedAS Chevrolet Camaro SS V8 6.2L Restricted Prep model years extended from 10–13 to 10–15.
  • SRF Mandatory identification: #30223wordingwordingSRF and SRF3 mandatory identification revised: removed Ford Performance and Blue Oval decals, added Hoosier logo placement.
  • 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.
  • AS Request for 2015 -2017 Ford Mustang Spec Line #29514cars addedaddedAS Ford Mustang GT 5.0L 15-17 Restricted added to Spec Line with 3600 lbs minimum weight, 55mm restrictor, 18×10 wheels, 295 tires.
  • AS Request Trunk lid / Rear Hatch clarification #29591wordingwordingAS underhood bracing on stock hoods, trunks, and rear decks may be modified or removed.
  • AS Common Weight for CTS-V Tire #29759weightfaster · weightAS Cadillac CTS-V 04-07 with 295 tire drops to 3450 lbs; Camaro SS V8 10-13 and Challenger 08-20 specs removed.
  • AS Correction to specifications inadvertently deleted #30041cars addedaddedAS Camaro & Firebird (93-02) and Mustang GT (05-14) specifications restored with weight minimums 3250–3500 and 3350–3600 lbs respectively.
  • FP Alternate Front Brake Rotors and Calipers for EP AH 3000 #29893otherotherEP Austin-Healey 3000 gains option to use TR-6 front calipers and discs as alternate.
  • FP Request VW weight break #29963weight -50 lbsfaster · weightFP Volkswagen Golf 1.8, Jetta, Rabbit and Scirocco gain 50 lb weight breaks, minimum weights to 1900–1733 lbs.
  • STU 13B Rules Adjustment #29333cars addedremoved · cars addedSTU Mazda 13B Spec and Bridge Port removed; Street Port added at 2400 lbs minimum weight.
  • AS Request Additional Engine Options for Dodge Challenger Spec Line #29543cars addedaddedAS Dodge Challenger gains 6.1L and 6.4L V8 options; 5.7L weight rises to 3500 lbs on 295 tyres, 3600 on 315 tyres; compression to 10.9:1 max.
  • AS Rule simplification spec line communization #29824cars addedcars addedAS Camaro & Firebird (93-02) and Ford Mustang Coupe GT (05-14) spec lines consolidated; Camaro/Firebird now allows both LT1 and LS1 engines; Mustang now allows both 4.6L 3-valve and 5.0L 4-valve engines with restrictor.
  • FP Mk2 VW Consistency and Cleanup of FP and HP Spec Lines #29195weight -50 lbsfaster · weightFP Mk2 Golf and Jetta 1.8 lose 50 lbs to 1900; HP Jetta GLI engine code removed.
  • FP Correct Wording for Level 1 and Level 2 Induction Systems #29406inductionfaster · inductionEP, FP, HP Level 1 and Level 2 induction systems: carburettor jets, needles, metering rods allowed; throttle body porting permitted; wording clarified.
  • FP Weight Reduction for Datsun Roadster #29409weight -75 lbsfaster · weightEP Nissan Datsun SRL 311U Roadster minimum weight reduced 75 lbs to 1925.
  • FP EP TR8 Adjustment #29512weight -100 lbsfaster · weightEP Triumph TR8 78-81 minimum weight drops to 2500 lbs.
  • FP Request to Classify 1996-2000 Honda Civic EX #29515cars addedaddedHonda Civic EX 96-00 classified FP2 at 1975 lbs, SOHC 1590cc, fuel injection, 56mm throttle body, comp ratio 12.0:1 max, valve lift 0.450" max.
  • FP FAJS Carburetor #29576cars addedaddedFP adds FAJS to permitted Weber-type and auto-type carburetor substitutes in two sections.
  • SRF SRF Shocks, Springs and Ride Height. #29688otherotherSRF rear springs limited to P/N 280390 only, previous part numbers no longer allowed; ground clearance wording clarified.
  • STU Request clarification on wing measurement #29640aeroaeroST aero devices and reference areas must include end plates, exclude fasteners under 1/2" protrusion.
  • FP 84-87 Toyota Corolla HP Wheel Diameter Allowance Proposal E&O #29458otherfasterHP 84-87 Toyota Corolla wheel diameter increases from 13 to 15 inches.
  • 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.
  • AS Dodge Challenger AS Spec Line Clarification #28698engineslower · engineAS Dodge Challenger 5.7L V8 now requires iron block instead of aluminum, compression to 10.5:1 max, intake valve 12.7 mm, exhaust 12.3 mm, intake timing 188 degrees, exhaust timing 205 degrees.
  • AS Dodge Challenger AS Spec Line Clarification #2 #28699aeroaeroAS Dodge Challenger 08-14 rear spoiler: 1GL20RXF replaced with 1GL20TZZAB; 82211606 still permitted.
  • FP EP BMW Z3 Rule Clarification #28998wordingwordingEP BMW Z3 2.5L cylinder head casting 1738400 permitted with iron block castings 1748933 or 1738566.
  • 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.
  • AS Support for R-Type Specification Tires #27450wordingunclearAS class pursuing specified list of eligible tires; list details unclear from text provided.
  • AS Spec Tire Request #27519wordingunclearAS class tire eligibility list under development; no specifications changed yet.
  • AS Restrictor Plate Change for RP 2011+ Mustang with Coyote Engine #27675wordingunclearAS Coyote Mustang restrictor plate under review for 2021; no change effective yet.
  • AS 2005-2009 Restricted Prep 4.6 3V #27908engineadded · engineAS Restricted Prep 4.6 3V now permits conversion to 2 valve configuration.
  • AS Request for 2005-2009 Restricted Prep 4.6 3V Parts #27909engineadded · engineAS Ford Mustang Coupe GT 4.6L 3V Restricted Prep now permits Ford Performance camshaft kit P/N M-6550-3V.
  • AS Request for Full Preparation Classification for 2010-2014 Camaro #28030wordingunclear2010-2014 Camaro remains classified in AS; no specification changes.
  • AS Cylinder Heads #28696wordingunclearAS class cylinder head supplier discontinuation; replacement option pending for 2021 season.
  • AS Request for Max Rotor Diameter Change #28748otherfasterAS Mustang, Capri, Camaro, and Firebird maximum brake rotor diameter increased from 12.2 to 13.1 inches.
  • AS Request increase rotor diameter #28797wordingunclearunclear
  • FP Request to Classify Porsche 911 2.0L #28456cars addedaddedPorsche 911 S 67-68 classified in EP at 1800–1890 lbs, 1991cc opposed 6-cylinder SOHC with 36mm carburetors.
  • FP Request to change to Carburetor Spec Line 84-87 Mazda 626 #28926wordingwordingFP Mazda 626 84-87 carburetor spec clarified to two auto-type sidedraft 32mm choke or fuel injection.
  • 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.
  • FP BMW Cylinder Head Casting and Part Numbers #28708engineslower · engineEP BMW 2.8L, 328i E36/E46, and 325i E36 now require iron blocks only; 325i E46 aluminum block removed.
  • FP Correct Scirocco Spec line E&O #28892cars addedaddedFP Volkswagen Scirocco E&O adds four engine variants with weights 1520–1853 lbs and displacements 1471–1780 cc.
  • STU Rotary Help #27833cars addedaddedSTU Mazda 13B Bridge Port and Street Port added with 2550 lbs and 2250 lbs minimum weight respectively.
  • AS weight adjustments for 2020 season #28785weight -50 lbs
  • FP Request to Classify 1990-1994 Mazda Protege #28381cars addedaddedFP Pre: 1990–1994 Mazda Protégé classified at 2150–2258 lbs, 1839cc DOHC, fuel injection, 11.0:1 compression, .450" valve lift limit.
  • FP Error in Mini Cooper Spec Line #28713wordingwordingHP Mini Cooper 02-06 and 07-13 convertible model years corrected to 05-08 and 09-15 respectively.
  • SRF SRF Bump Stop Correction #27019wordingwordingSRF Penske shock P/N 280396 bump stop P/N 280407 becomes mandatory, maximum one per shock, effective 05/01/2020.
  • FP Caterham 7 Spec Line #28498wordingwordingEP Caterham 7 America engine limited to IT prep with specific sections, comp ratio 10.0:1, valve lift .380 inch.
  • FP Request to classify SOHC 1989-90 240SX in F prod L2 #28553cars addedadded1989-90 Nissan 240-SX SOHC added to FP Pre L2 at 2400–2520 lbs, 2389 cc, fuel injection, 11.0:1 compression, .450" valve lift limit.
  • 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.
  • FP VW Weight and Valve Size Request #27886wordingwordingFP Volkswagen Jetta, Rabbit, Scirocco reclassified with weights 1520–1853 lbs, intake valves 40.0 mm, exhaust 33.0 mm, throttle 35/52 mm.
  • FP Request to allow 40 DCOE carb for the Datsun 510 #28195engineadded · engineHP Datsun 510 allows 40 DCOE carburetor option alongside existing 40 DCNF and 36mm DCNVH; auto side drafts moved to penalty structure.
  • FP Request to classify Porsche 914 2L in LPrep FProd #28231cars addedaddedPorsche 914-4 2.0L classified in FP Prep 2 at 2030–2132 lbs with 1968cc OHV engine, Solex/Weber/Dellorto carbs or fuel injection, 11.0:1 compression limit, .450" valve lift limit.
  • FP Request Ford Fiesta Weight Adjustment #28336weightfaster · weightFP Ford Fiesta 78-80 minimum weight reduced 130 lbs, to 1660.
  • 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.
  • AS Rear Trailing Arms #28007suspension & brakesadded · suspension & brakesAS rear trailing arms may be replaced with tubular arms maintaining stock length and axle location purpose only.
  • AS Weight reduction for cars running iron heads #28010weightfaster · weightAS Ford and GM full prep cars get increased weight reduction from 150 to 200 lbs.
  • AS 05-10 Mustang with HR cam classification #28226cars addedadded05-10 Ford Mustang Coupe GT 4.6L OHC classified AS with 3200 lbs minimum weight, HR cam permitted.
  • AS 10-15 Camaro Full Prep classification #28227cars addedadded10-15 Camaro Full Prep classified AS with 3400 lbs base weight, 3700 lbs over 313 CID, specific head castings and Edelbrock heads permitted.
  • FP Request for Help for Datsun 1200 #27934inductionfaster · inductionHP Datsun 1200 carburetor option changes from 26mm to 30mm choke(s) in 40 DCN, DCNF, IDF.
  • FP Request to List Mazda Miata Throttle Body Size #27907wordingwordingMazda Miata models EP and FP throttle body specified 55mm, brake rotor thickness figures removed.
  • FP Request to Classify 2001-2003 Mazda Protege ES in FP #27922cars addedaddedFP Mazda Protégé ES 2001–2003 newly classified at 2350–2468 lbs with 1991 cc DOHC four-cylinder, fuel injection, 11.0:1 compression, .450 in. valve lift limit.
  • SRF SRF Rain / Brake Rule - BoD approved as follows #34958wordingwordingSRF rain and brake rule supersedes GCR 9.3.32.B.2 effective 1/1/2024 through 12/31/2024.
  • FP Request to Correct Track of 1988-91 Honda Civic #27487otherotherFP and HP: 1988–91 Honda Civic and CRX track widths corrected to 61.3 / 61.7 inches across multiple levels.
  • FP Re-organize Prep2 Cylinder Head Rules for Clarity & Consistency #27661wordingwordingEP, FP, HP cylinder head rules reorganized for clarity; no performance change.
  • SRF SRF Tire Warmer Rule #27622tyres & wheelstyres & wheelsSRF adds tire warmer prohibition and specifies Hoosier dry and wet tire part numbers.
  • SRF SRF / SRF3 Nose Weight Reduction #27706weightfaster · weightSRF front nose weight minimum reduced from 35 to 32 lbs.
  • SRF SRF / SRF3 Majors & Regional Class Updates #27723wordingwordingSRF2 becomes Regional Only; SRF3 nomenclature changed from GEN3 to Ford 1.6L conversion; SRF and SRF3 no longer compete together for points.
  • 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.
  • AS Request to add SMG to 9.1.6.B.1 AS Intent #27140cars addedaddedAS Spec Mustang (SMG) added as Restricted Prep class.
  • FP Request bodywork for Austin Healey Bugeye Sprite MK1 #27106aeroadded · aeroFP and HP Austin-Healey Sprite Mk I / MG Midget may replace rear bodywork aft of cockpit with alternate material stock-appearing components.
  • FP Request to classify the GMX5 2019 #27263cars addedaddedEP Mazda MX-5 Global Cup classification updated to include 2019 model year.
  • FP level one susp. component rule #27270wordingwordingProduction classes: suspension rule clarified to specify spindles, hubs, bushings, bearings, and ball joints unrestricted.
  • FP Clarification of Carb Rules - Prep 1 #27300wordingwordingProduction carburetor and fuel injection rules clarified: permitted optional carburetors listed, Weber and auto-type substitutions specified, fuel injection throttle body and butterfly dimensions detailed, intake manifold port extension pr…
  • FP Clarification of Carb Rules - Prep 2 #27301inductioninductionEP, FP, HP carburetors: jets, needles, metering rods, needle valves unrestricted; choke parts removable; stock or optional Weber 40 DCN permitted; Weber types, auto types listed.
  • STU Request to correct E&O advanced aerodynamics #27290wordingwordingSTU wing assembly wording corrected: no part may be higher than roof height.
  • AS Request Ride Height Clarification #26598wordingwordingAS class ride height minimum clarified: five inches measured at rocker panel, excluding seams and stock effects.
  • FP Request Miata Eligibility - 2003 #27121cars addedaddedEP Mazda MX-5/Miata model years expand from 1999-2002 to 1999-2005.
  • SRF SRF Dash Windscreen Kit #27028aeroadded · aeroSRF drivers may now use Dash Windscreen Kit P/N 1180103 or P/N 180102.
  • 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.
  • AS Request to Revert to 2017 Weights #25885weightfaster · weightAS Ford Mustang 79-93 non-Cobra drops 100 lbs to 3150; over 313 CID Cobra drops 100 lbs to 3450.
  • 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.
  • FP Rollcenter Correction Clarification #25873wordingaddedEP, FP, HP: clarified that tapered holes in ball joints can be reamed for bolt conversion, and wheel bearings and hubs unrestricted on all axles.
  • FP Hardtops #26476aeroadded · aeroEP open cars may now use aftermarket hardtops if OEM-appearance and non-carbon-fiber; specific model allowances removed as redundant.
  • 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.
  • FP Request Classification of Dodge Daytona in F Production #26259weight -150 lbsfaster · weightFP Dodge Daytona/Chrysler Laser 84-85 added at 2100 lbs; Shelby Charger/Omni 024 83-84 weight cut to 2100 lbs.
  • 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.
  • AS SMG Mustang eligibility in American sedan #26224cars addedaddedAS adds Spec Mustang SMG classification with 107.1 wheelbase, 3.73 gears, 355mm front and 300mm rear brakes.
  • 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 AS" is the class's best as a share of AS'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 AS'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.