SRF3 + FA + GT1 + STU at Buttonwillow Raceway Park

2024-03-01 STU Letter #35397 addendum

#35453 from Aaron Fitzsimmons · Rule change · TB 24-03 (2024-03 Fastrack)

In STU Spec Lines, Mini Cooper S SC with Minimum Weight 1900 and 2100, add to Notes:
"Alternate LEAP OMICRON hood scoop part # LEP-OMICRON3 is permitted."

2024-03-01 STU S54 Drysump

#35464 from Macey Urso · Rule change · TB 24-03 (2024-03 Fastrack)

In STU Spec Lines, BMW S54 B32 OEM, add to Notes as follows:
"Dry Sump oiling system permitted."

2024-05-01 GT1 Request for Spec Line 1010 Reconsideration

#35009 from Kristofer Olson · Rule change · TB 24-05 (2024-05 Fastrack)

In GT2-ST Spec Lines, Acura NSX, change as follows:
Minimum Weight: "2700 3000"
Restrictor: "43 45mm TIR"

2024-05-01 GT1 Camaro 1993- and 2010-

#35652 from John Bodnar · Rule change · TB 24-05 (2024-05 Fastrack)

In GCR, Section 9.1.2.E.1.b.3., change as follows:
"Camaro (1993-2002)"

2024-06-01 SRF3 SRF3 Alternator Pulley Update In

#36095 from Robey Clark · Rule change · TB 24-06 (2024-06 Fastrack)

SFR3, GCR section 9.1.8.D.2.H.17, change as follows:
"Alternator Pulley: P/N G902130, or P/N G902130A, or P/N G902131 (six row). 12 11 oz minimum weight."

2024-08-01 STU RWD Turbo Disadvantage

#36255 from David Fiorelli · Rule change · TB 24-08 (2024-08 Fastrack)

In GCR, Section 9.1.4.1.H.3 - Inlet Restrictor (mm) Minimum Weight (lbs) table, change as follows:
"RWD cars must reduce restrictor 1 mm from this table"

2024-08-01 SRF3 Update Rain Tire Rule and Hoosier Decal Placement

#36436 from Robey Clark · Rule change · TB 24-08 (2024-08 Fastrack)

In SRF, GCR section 9.1.8.D.1.X.f, change as follows:
"Wet:
Front – Hoosier P/N 46100 P185/60R13 H20 or W2
Rear – Hoosier P/N 46105 P205/60R13 H20 or W2
Ground clearance is 2.5” with driver as raced when P185/60R13 (H20 or W2) tires are used.
OR
Front – Hoosier P/N 46101 P185/65R13 W2
Rear – Hoosier P/N 46105 P205/60R13 W2

2024-09-01 SRF3 Update to Letter 36619 with new Hoosier Contingency Decal Info

#36624 from Robey Clark · Rule change · TB 24-09 (2024-09 Fastrack)

In SRF, GCR section 9.1.8.D.1.X.f.3, change as follows:
"Four (4) "Hoosier" decals are required in the following locations: Two (2) 11" X 3" decals on the vertical plane of the front nose
to the outside of the cooling opening on each side and two (2) 18" X 5" decals, one on each side of the engine cover or above the
rear wheel openings on the vertical plane. Hoosier decals are available, free of charge, from all Hoosier tire distributors including
SCCA Enterprises Per Hoosier's contingency program, three (3) decals are required to qualify for contingency awards. One (1)
decal must be located on each side of the car and one (1) decal must be visible on the front."

2024-10-01 SRF3 Update SRF3 Air Filter Rule

#36681 from Robey Clark · Rule change · TB 24-10 (2024-10 Fastrack)

In SRF, GCR section 9.1.8.D.2.H.23, change as follows:
"Air Filter: P/N WM301020 or K&N RC-9160"

2024-10-01 SRF3 Update SRF Brake Rotor Thickness

#36687 from Robey Clark · Rule change · TB 24-10 (2024-10 Fastrack)

In SRF, GCR section 9.1.8.D.1.X.g, change as follows:
"Brakes: Hawk Blue 9012 pads P/N 801993 must be used. Wilwood vented rotor P/N 800065 shall must be used as delivered with
no machining of any kind. Minimum thickness 12.20mm (0.481”) 13.25mm (0.522”)."

2024-10-01 SRF3 Hoosier Tire Decal Placement

#36739 from Robey Clark · Rule change · TB 24-10 (2024-10 Fastrack)

In SRF, GCR section 9.1.8.D.2.B, change as follows:
"Mandatory identification: "SRF3" near the side car numbers. "Hoosier" logo (4) on both sides front lower outer corners of the
nose and each side of the tail. Three (3) "Hoosier" logos, one (1) on each side of the car and one (1) on the center front of the car."

2024-11-01 GT1 Request to Classify Mazda 26B Engine

#36230 from Wayne Graham · Rule change · TB 24-09 (2024-09 Fastrack)

In GT1 Spec Lines, GT1 Approved Automobile List, Mazda, add the following:
"(Effective 11/1/2024) 26B engine = 2850 lbs."

2024-11-01 STU R53 15% Pulley Request

#36980 from Aaron Fitzsimmons · Rule change · TB 24-11 (2024-11 Fastrack)

In STU Spec Lines, Mini Cooper S SC, add to notes:
1900: "Stock supercharger pulley. 2.565 diameter."
2100: "JCW Pulley permitted. May run a 2.285 diameter pulley."

2024-12-01 GT1 Lamborghini Huracan GT3 Evo Restrictor Help

#36254 from Michael McAleenan · Rule change · TB 24-12 (2024-12 Fastrack)

In GT1-ST Spec Lines, Lamborghini Huracan GT3 EVO(1) (2018-), change Restrictor as follows:
"2 X 39mmUnrestricted"
In GT1-ST Spec Lines, Lamborghini Huracan GT3 (2019-), change Restrictor as follows:
"52mm Unrestricted"

2024-12-01 STU Request to Remove Miata Hubs from General category

#37138 from Christopher Childs · Rule change · TB 24-12 (2024-12 Fastrack)

In GCR, Section 9.1.4.M.18., change as follows:
"18. Allow alternate front wheel front hubs, Mazda Motorsports Development Part #0000-04-5HUB-S1, for the 90-05 Mazda
Miata: Mazda Motorsports Development Part #0000-04-5HUB-S1."

2024-12-01 STU BMW N54/N55 Engine Allowance

#37146 from Martin Sarukhanyan · Rule change · TB 24-12 (2024-12 Fastrack)

"Turbo inlet restrictors designed per GCR Appendix F Technical Glossary definition of “Turbo Inlet Restrictor” may be required;
see table 9.1.4.1.H.h.2 3. Swapping of turbochargers between engine makes and models is prohibited. Supercharged cars may be
approved on a case-by-case basis; twin turbo engines are allowed on a case-by-case basis only. Contact the Road Racing
Technical Office for details. Twin turbo engines may be converted to single turbo using one of the allowed alternate turbos (see
9.1.4.1.H.3 2). Aftermarket turbocharger and supercharger kits will be allowed on a case-by-case basis.

2025-01-01 STU Audi 1.8t Wagon STU Table B

#36685 from Mike McLaughlin · Rule change · TB 25-01 (2025-01 Fastrack)

In STU Spec Lines, Table B: Alternate Vehicle and Engine Requirements, delete Audi/VW 1.8 Turbo in its entirety.
In STU Spec Lines, Table B: Alternate Vehicle and Engine Requirements, Porsche 944 w/Max Displacement 1800, change as
follows:
Weight: "3050 Chart"
Notes: "VW/Audi 1.8L 35mm turbo engine permittedinlet restrictor required."

2025-01-01 GT1 Addition of a limited prep LS Chevy engine for GT1

#37045 from Robert Logsdon · Rule change · TB 25-01 (2025-01 Fastrack)

In GCR, Section 9.1.2. GT1 Spec Lines, GT1 Approved Automobile List, LS1 V8 engine allowed with stock intake, add the
following:
"LS1 Limited Prep GT1 motor
2600 # with driver
Blocks : GM castings or aftermarket, no lightening, Max volume 383 cubic inches
Cylinder Heads: GM LS castings or aftermarket, stock valve angle, intake and exhaust ports must be in stock location, porting
and polishing allowed
Valves: No titanium valves, must be stock size for head part number

2025-01-01 GT1 Correct language regarding OEM Areo Devices

#37137 from Christopher Childs · Rule change · TB 25-01 (2025-01 Fastrack)

In GCR, Section APPENDIX L. 2013 TA2 TECHNICAL REGULATIONS, B.2.c., change as follows:
"B. Aerodynamic Devices
2. Rear wing
c. The entire rear wing assembly, including the end plates and any Gurney flap, shall be mounted level
with, or below, the peak of the roof. OEM aerodynamic devices do not need to adhere to the height rule."

A specification table follows in the original; it is not shown here.

2025-01-01 GT1 GT1-ST Adjustments

#37481 from Grand Touring Committee · Rule change · TB 25-01 (2025-01 Fastrack)

In GT1-ST SPEC LINES, change as follows:
Aston Martin Vantage GT3 (2012) :
Restrictor: "2 x 41.5mm"
Audi R8 LMS Ultra GT3 (10-14) :
Restrictor: "2 x 49mm"
BMW Z4 GT3 (10-13):
Restrictor: "70mm"
Chevrolet Corvette C8 (20-):

2025-01-01 STU Merger GT3 to STU

#37486 from Club Racing Board · Rule change · TB 25-01 (2025-01 Fastrack)

In STU, Table C, change STU-GT3 charge as follows:
"(Effective January 1, 2026) TABLE C: STU-GT3U"

2025-01-01 STU GT3 TCR Tire allowance

#37494 from Club Racing Board · Rule change · TB 25-01 (2025-01 Fastrack)

In STU, Table C, GT3 TCR, add to Notes the following:
"May run DOT approved tire with maximum section width of 275 with 100 pound weight adder. May not run A compound with
275."

2025-02-01 FA Classify FR European Championship car as spec line car in Table 2

#37658 from Club Racing Board · Rule change · TB 25-02 (2025-02 Fastrack)

In FA Table 2, add the following:
Table 2 (Spec Line Cars)
Car Engine
Wheel
Width (in)
± .060
Aero Transmission Weight Notes

A specification table follows in the original; it is not shown here.

2025-03-01 GT1 Request to Classify Acura NSX GT3 Evo 22

#37367 from Taz Harvey · Rule change · TB 25-03 (2025-03 Fastrack)

In GT1 Spec Lines, GT 1 Cars - ACURA, classify Acura NSX GT3 EVO 22 as follows:
GT 1 Cars - ACURA
Model Years Body Style Drive-
line
Wheel-
base (in)
Notes
Acura NSX GT3 EVO 22 N/A 2dr RWD 103.5 Ground Clearance 50mm

A specification table follows in the original; it is not shown here.

2025-03-01 STU BMW N54/N55 Engine Allowance Follow Up

#37447 from Martin Sarukhanyan · Rule change · TB 25-03 (2025-03 Fastrack)

In STU Spec Lines, Table A, classify BMW N54/N55 as follows:
STU Maximum Displacement
(cc's) Minimum Weight Notes
BMW N54/N55 3.0 Chart +3% (DI) Short blocks, heads, and intakes may be
freely swapped within these engine
designations. N54 twin turbo not allowed

2025-03-01 STU STU Mini Cooper pulley size clarification re: letter #36980

#37717 from Aaron Fitzsimmons · Rule change · TB 25-03 (2025-03 Fastrack)

In STU Spec Lines, Mini Cooper S SC, add to notes:
2100: "May run a 2.285 2.185 diameter pulley."

2025-03-01 STU Question About a Weight Modifier

#37782 from Peter St Pierre · Rule change · TB 25-03 (2025-03 Fastrack)

In STU Spec Lines, Table A, Honda K20C1 Turbo I4, add to Notes the following:
"The 3% DI weight adder does not need to be applied."

2025-03-01 FA Update Formula Renault 2.0 spec line notes

#37853 from Club Racing Board · Rule change · TB 25-03 (2025-03 Fastrack)

In FA Table 2, Formula Renault 2.0 (10-17) spec line, change the notes as follows:
"Engine must remain sealed. Car must comply with year-specific Formula Renault 2.0 manual, technical regulations, and all
applicable bulletins found here:. Competitors must have copies of these materials in their possession and present them upon
request.
https://sites.google.com/a/renault-sport.com/formule-renault-2-0-en/bulletins-techniques/2017,
https://sites.google.com/a/renault-sport.com/formule-renault-2-0-en/manuel-d-utilisateur/2017.
The following exceptions apply: Tire choice is unrestricted. No part of the car may be altered from original Formula Renault 2.0
components, except for necessary repairs that do not affect performance."

2025-03-01 STU Increase Minimum Weight

#37919 from Club Racing Board · Rule change · TB 25-03 (2025-03 Fastrack)

In STU Spec Lines, Table C: STU-GT3U, change Minimum Weight as follows:
"150 250 pounds"

2025-04-01 SRF3 Driver Safety & Comfort

#37966 from Robey Clark · Rule change · TB 25-04 (2025-04 Fastrack)

In SRF, GCR section 9.1.8.D.1.D, add the following:
"f. Driver Safety and Comfort modifications to seat and controls for drivers with disabilities may be made only by approval. These
modifications must be reported to SCCA Enterprises and noted in the car logbook. The modifications are approved only for the
noted driver with disabilities. If the car is used by or sold to another driver, it must be returned to the previous standard
configuration."

2025-04-01 SRF3 Update SADEV transmission specs

#37992 from Club Racing Board · Rule change · TB 25-04 (2025-04 Fastrack)

In SRF, GCR section 9.1.8.D.2.K, change as follows:
"OR
SADEV-SRF3 6-Speed Sequential (beginning from Oct. 4, 2021 onward):
1st 12-36 3.0000 : 1
2nd 15-31 2.0667 : 1
3rd 18-28 1.5556 : 1
4th 22-28 1.2727 : 1
5th 24-26 1.0833 : 1

2025-05-01 STU Wheel Size Inconsistency

#38018 from David Fiorelli · Rule change · TB 25-05 (2025-05 Fastrack)

In GCR, Section 9.1.4.1.F.1., change as follows:
"Wheels may not exceed 18 inches in diameter. or 8.0 inches in width for vehicles 2950 lbs. and under minimum allowed race
weight. Vehicles over 2850 minimum allowed race weight may use a 9 inch wide wheel. Cars equal to or less than 2,850 lbs.
minimum allowed race weight may not use wheels wider than 8 inches. Cars greater than 2,850 lbs. minimum allowed race
weight may not use wheels wider than 9 inches."

2025-05-01 STU Table C: STU-GT3U Clarification

#38268 from Club Racing Board · Rule change · TB 25-05 (2025-05 Fastrack)

In STU Spec Line, Table C: STU-GT3U, change as follows:
Minimum Weight: “Current GT3 race weight plus 250 225 pounds”
Notes: "DOT approved tire with maximum section width of 245. GT3 cars base wheel is a maximum of 15”x9”. 18”x9” wheels
allowd with a 3% weight addition. GT3 cars utilizing 15”x7” wheels are limited to a maximum section width of 225 with a 25
pound weight reduction"
"All GT3U (Majors and Runoffs) cars using up to 15"x7" wheels limited to 225 section width tires shall run at current GT3 race
weight plus 225lbs. All Gt3U cars shall run a DOT approved tire with a maximum section width of 245. GT3U cars are allowed
optional 15"x9" wheels with a 1.5% weight addition or up to 18"x9" wheels with a 3.0% weight addition to the total weight

2025-07-01 STU 2.8-3.2L N/A Engine Allowances

#38007 from Ben Slechta · Rule change · TB 25-07 (2025-07 Fastrack)

In GCR, Section 9.1.4.G.1, add the following:
"A maximum section width of 245 is permitted. Cars over 3150 lbs. may run a 275 tire with a 2% weight adder."

2025-07-01 STU 2006-2015 Mazda Miata Intake Manifold

#38422 from German Candelario Candelario · Rule change · TB 25-07 (2025-07 Fastrack)

In STU, Table A, Mazda MZR (LF, L3, L5), change Notes as follows:
"May use Goodwin Part # 61-2510 or Gato Performance Part #31972 Intake manifold . "

2025-07-01 FA Ligier JS F3 Tire Choice

#38434 from Rocco Magni · Rule change · TB 25-07 (2025-07 Fastrack)

In FA Table 2, FR Americas Ligier JS F3 spec line, change the notes as follows:
"Engine must be sealed in compliance with FR Americas or prior F3 Americas requirements. Car must comply with FR Americas
rules, with the following exception: front tires may be Hoosier P/N 43363, size 240/580R13 in MS compound, and rear tires may
be Hoosier P/N 43368, size 300/590R13 in MS compound. Competitors must have current copies of Formula Regional Americas
Championship Sporting Regulations, Onroak Automotive Ligier JS F3 Information Manual, and HPD engine-related specifications
and instructions in their possession and present them upon request."

2025-07-01 STU Requesting Approval of the JDM Honda h23a

#38489 from Eric Fiest · Rule change · TB 25-07 (2025-07 Fastrack)

In STU, Table B, classify Honda JDM H23a as follows:
STU Maximum Displacement (cc's) Minimum Weight Notes
Honda JDM H23a 2259 Chart Must meet all ST engine regulations.

2025-08-01 STU STU-TCR Adjustments

#38723 from Club Racing Board · Rule change · TB 25-08 (2025-08 Fastrack)

In STU Spec Lines, Table C: STU-GT3U, GT3-TCR, change as follows: Remove the current TCR spec line and add the TCR spec lines
from GT3 that are being removed, adding the below to the notes.
"DOT approved tire with maximum section width of 245. May run DOT approved tire with maximum section width of 275 with
100 150 pound weight adder. May not run A-compound with 275. STU-TCR spitters and side valance must comply with
9.1.4.D.3.f. STU-TCR chassis ride height must comply with 9.1.4.1.A.1."

2025-08-01 STU Lotus Weight Reduction

#38772 from Club Racing Board · Rule change · TB 25-08 (2025-08 Fastrack)

In 9.1.2. GT2/ST Spec Lines, Lotus Evora GT4, change Weight as follows:
"2750 2700"
In STU Table B: Alternate Vehicle and Engine Allowances, change Weight as follows:
Lotus Elise Cup R: "2300 2250"
Lotus Elise SC/ Lotus Exige SC: "2300 2550
2500 2450"

2025-09-01 SRF3 SRF Rule Updates

#38853 from Robey Clark · Rule change · TB 25-09 (2025-09 Fastrack)

Effective 9/1/25 in SRF, GCR section 9.1.8.D.1.V.ff, add the following:
"SRF3 Oil Cooler, P/N G480503 may be used as mounted per the GEN3 Assembly Manual. No fan permitted for SRF. HD Oil
Cooler kit P/N G1148500 may be used as mounted per the GEN3 Conversion Manual."
Effective 9/1/25 in SRF, GCR section 9.1.8.D.X.g, change as follows:
"Brakes: Hawk Blue 9012 pads P/N 801993 must be used. Wilwood vented rotor P/N 800065 must be used as delivered with no
machining of any kind. Minimum thickness 13.25mm (0.522”). The Renault Alliance solid front rotors may not be used. Rubber
caliper bushings may be replaced with bronze bushings P/N 1196185 or P/N 1196185. Original caliper pistons may be replaced
with vented caliper piston P/N 1196184; no other modification allowed. Wilwood caliper with bracket universal fit P/N 800038

2025-09-01 GT1 Correction to Limited prep LS Chevy engine for GT1

#38902 from Robert Logsdon · Rule change · TB 25-09 (2025-09 Fastrack)

In GCR, Section 9.1.2. GT1 Spec Lines, GT1 Approved Automobile List, LS1 engine allowed with stock intake, make the following
change:
"LS1 Limited Prep GT1 Motor Chevy LS Limited Prep Engine including LS1, LS2, LS3 and LS6."
"Pistons: Factory or aftermarket flat top pistons only, valve reliefs allowed, coatings allowed. Maximum compression ratio
11:1."

2025-09-01 STU Lotus Weight Reduction E&O

#38919 from Club Racing Board · Rule change · TB 25-09 (2025-09 Fastrack)

In STU Table B: Alternate Vehicle and Engine Allowances, change Weight as follows:
Lotus Elise SC/ Lotus Exige SC: "2450 2250"

2025-10-01 SRF3 Add HD Oil Cooler

#38979 from Robey Clark · Rule change · TB 25-10 (2025-10 Fastrack)

In SRF, GCR section 9.1.8.D.1.V.ff, change as follows:
"SRF3 Oil Cooler, P/N G480503 or HD Oil Cooler P/N G1148500 may be used as mounted per the GEN3 Assembly Manual. No fan
permitted for SRF. HD Oil Cooler kit P/N G1148500 may be used as mounted per the GEN3 Conversion Manual."

2025-10-01 GT1 RM 25-06 GT1 reclassify the Acura NSX GT3 EVO 22 to GT1-ST

#39101 from Club Racing Board · Rule change · TB 25-10 (2025-10 Fastrack)

IN GT1 reclassify the Acura NSX GT3 EVO 22 to GT1-ST as follows:
GT1 Approved Automobile List
Make/Model Wheelbase
ACURA
NSX GT3 EVO 22 103.5”
DOHC 4v per cylinder EFI Twin Turbo Crossflow V-6 Displacement 3500cc Bore and Stroke 91x90
MAX RPM 7500 MAX BOOST 2.1 bar Weight 3100 lbs
GT1-ST Maximum

2025-11-01 STU Non-Homologated Engine Swaps - Specifically K24A2 w/ Honda CRZ

#38746 from William Rori · Rule change · TB 25-09 (2025-09 Fastrack)

In STU Spec Lines, Table B: Alternate Vehicle and Engine Allowances, Honda K24, change Weight as follows:
"(Effective 11/1/2025) Chart + 2%"

2025-11-01 FA Re-Consider USF Pro 2000 Car for Formula Atlantic Class

#38783 from Augie Pabst · Rule change · TB 25-09 (2025-09 Fastrack)

Effective 11/1/25 in FA Table 2, add the following:

2025-12-01 STU Turbo Inlet Restrictor Table

#38961 from John Weisberg · Rule change · TB 25-12 (2025-12 Fastrack)

In GCR, Section 9.1.4.H.3, change chart as follows:

A specification table follows in the original; it is not shown here.

2025-12-01 STU 275 Tire Rule

#38983 from Peter Federlin · Rule change · TB 25-12 (2025-12 Fastrack)

In GCR, Section 9.1.4.G.1., change as follows:
"A maximum section width of 245 is permitted. Cars over 3150 lbs. may run a 275 tire with a 2% weight adder."

2025-12-01 STU STU Honda Engine weight penalty

#39375 from Super Touring Committee · Rule change · TB 25-12 (2025-12 Fastrack)

In STU Spec Lines, Table B: Alternate Vehicle and Engine Allowances, change Minimum Weight as follows:
Honda K20: "Chart + 2%"
Honda K24: "Chart + 2%"

2026-01-01 FA Alternate Intake Manifold for MZR

#38223 from Ove Olsson · Rule change · TB 26-01 (2026-01 Fastrack)

In FA, GCR section 9.1.1.2.d, modify as follows:
"9. Intake manifold must be unmodified Elan DP02-60-003 or Mazda Speed equivalent Elite USF2015AT, 1.882” maximum bore
diameter at throttle plates. Elan or Mazda Speed equivalent Elite intake manifold may be replaced with unmodified intake Noor
P/N 0088-8-00 with intake runners AT Power P/N 13624."
"10. Elan DP02-60-003 or Mazda Speed equivalent Elite USF2015AT intake manifold must use an A aluminum spacer must be
used between the intake manifold and cylinder head castings; minimum spacer length is 2.200”."

2026-01-01 FA Engine Compression Rule Change Request

#39302 from Reilly Harris · Rule change · TB 26-01 (2026-01 Fastrack)

In FA Table 2, Formula 1000 spec line, change the Engine as follows:
"Motorcycle-based 4-cycle up to 1000cc, maximum compression ratio 14.5:1;. o Otherwise, current FA engine rules apply."

2026-01-01 GT1 NSX Parity With Other GT3s Let Alone a GT1 Car

#39311 from Taz Harvey · Rule change · TB 26-01 (2026-01 Fastrack)

In GT1-ST, Acura NSX GT3 EVO 22, change Weight as follows:
"3100 3000"

2026-01-01 STU Request for Permission on Aftermarket Turbo Kit and Intake

#39529 from John Grim · Rule change · TB 26-01 (2026-01 Fastrack)

In STU Spec Lines, Table A: Alternate Vehicle and Engine Allowances, Mazda MZR (LF, L3, L5), change Notes as follows:
"Short blocks, heads, and intakes may be freely swapped within these engine designations. May use Goodwin Part # 61-
2510 or, Gato Performance Part #31972 or Jack Spania Racing 70 mm sheet-metal aluminum Intake manifold. Must use stock
throttle body or Acura part number 16400-PND-A17."
In STU Spec Lines, Table A: Alternate Vehicle and Engine Allowances, classify Mazda MZR (LF, L3, L5) Turbo as follows:
STU Maximum Displacement (cc's) Minimum Weight Notes
Mazda MZR (LF, L3,
L5) Turbo

2026-01-01 FA Change Formula 1000 allowances

#39608 from Club Racing Board · Rule change · TB 26-01 (2026-01 Fastrack)

In FA Table 2, Formula 1000 spec line, change the Notes as follows:
"Car must comply with December 2019 GCR Formula 1000 (FB) Preparation Rules, https://www.scca.com/downloads/48184-
gcr-december-2019/download, except as modified by this spec line. The prohibition of using carbon fiber in any external panels
or any panels licked by the airstream in Part 3.C of the December 2019 GCR F1000 (FB) Preparation Rules is removed, with the
exception that the car's floor pan/undertray must comply with the requirements of Part 2.D of the December 2019 GCR F1000
(FB) Preparation Rules. The prohibition of forward-facing gaps or openings in the bodywork in Part 3.I of the December 2019 GCR
F1000 (FB) Preparation Rules is removed. Part 3.D of the December 2019 GCR F1000 (FB) Preparation Rules is modified as
follows: "Between the rear of the front tire and the front of the rear tire, no point on the lower surface of the car (the surface

2026-02-01 GT1 Request for Addition of Porsche 992.1 GT3 Cup into GT1

#39322 from Erik Madsen · Rule change · TB 26-02 (2026-02 Fastrack)

In 9.1.2. GT1 Spec Lines, add the following:
"992.1 GT3 Cup (2022-2025)
OEM ABS and Traction Control allowed. Porsche OEM RSR bumper and canards allowed. Any exhaust system may be utilized."

2026-02-01 FA Pro Mazda Classification and Performance Enhancement Proposal

#39411 from Stephen Lamana · Rule change · TB 26-02 (2026-02 Fastrack)

In FA Table 2, Pro Formula Mazda spec line, change the notes as follows:
"All current FA rules apply to areas not covered by this spec line. Apex seals unrestricted. Street port or bridge port
allowed. Unmodified OEM l Lower intake manifold required unrestricted, upper intake manifold unrestricted. Balance tube not
permitted. Fuel injection only. Maximum 70 80mm T throttle B body. The maximum height of the wing and/or
endplates shall must not exceed 99cm (38.98 inches). The overall maximum width of the bodywork behind the front
wheels shall must not exceed 132cm (51.97 inches)."