BoP Lab / Buttonwillow Raceway Park

STU + STL + AS at Buttonwillow Raceway Park

No mapCal Club 2024, Cal Club 2023

This track has been raced on 4 configurations (The Circuit, 2.57 mi; 19, 2.92 mi; 1.83 mi; 3.02 mi). Laps on different configurations are not comparable, so only events on the 2.57 mile layout are shown; switch above to see the others.

6 laps are left out as timing errors (far too short to be a lap of this track). The rest of those sessions, sectors included, is used.

Pos	Car	Driver	Class	#	Lap	Theoretical	Qual	Race	5-lap stint	Consistency	Trap	S1	S2	S3
1	Mazda RX-3	Tony Rivera	STU	09	1:50.913 A-Q2	1:50.870	1:50.913 A-Q2	1:52.737 A-R2	1:54.126 A-R2	+2.638 A-R2	135.2 A-Q2	30.415 A-Q2	32.456 A-Q2	47.999 A-Q2
2	Mazda Miata	Whitfield Gregg	STU	17	1:51.602 B-P	1:51.602	2:02.264 B-Q2	2:01.538 B-R1	2:02.222 B-R1	+1.271 B-R1	116.3 A-Q1	30.652 B-P	32.263 B-P	48.687 B-P
3	Mazda MX-5	Jared Korth	STL	27	1:51.665 B-P	1:51.645		1:58.002 A-R2	1:58.825 A-R2	+1.245 A-R2	134.8 A-R1, A-R2	30.616 B-P	32.218 B-P	48.811 B-P
4	BMW M3	Wilson Powell	STU	77	1:52.380 B-P	1:52.164	1:55.401 B-Q1	1:53.843 B-R1	1:54.699 B-R1	+1.965 B-R1	102.6 B-R1	30.577 B-P	32.372 B-P	49.215 B-P
5	Mazda Miata	Wesley Mollno	STL	10, 11, 111	1:52.983 B-P	1:52.983	1:59.582 A-Q1	1:59.163 A-R1	1:59.870 B-R2	+0.510 B-R2	133.4 A-Q1	30.838 B-P	33.020 B-P	49.197 B-P
6	Mazda Miata	Jon Davies	STL	67	1:53.071 B-P	1:53.071	1:59.281 B-Q1	1:59.121 B-R1	1:59.683 B-R1	+1.145 B-R1	127.3 B-P	30.815 B-P	32.820 B-P	49.536 B-P
7	Mazda RX-8	David LeCren	STL	2	1:53.515 B-P	1:53.253	2:09.464 A-Q2	2:11.372 A-R2	2:11.978 A-R2	+5.025 A-R2	121.0 A-Q2	31.217 B-P	32.486 B-P	49.550 B-P
8	Honda S2000	Rylan Hazelton	STU	49	1:53.640 B-R1	1:53.140	1:55.834 B-Q1	1:53.640 B-R1	1:54.534 A-R2	+0.714 A-R2	134.8 A-R2	30.582 B-R1	32.779 B-R1	49.779 A-R2
9	Mazda Miata	Sayo Haraishi	STL	34	1:54.120 B-P	1:54.019	2:08.265 B-Q1	2:09.190 B-R1	2:09.557 B-R1	+0.759 B-R1	105.6 B-P	31.129 B-P	33.359 B-P	49.531 B-P
10	Mazda MX-5	Ricardo Arruda	STL	16	1:54.343 B-P	1:54.343	2:00.717 B-Q2	2:01.410 B-R1	2:02.207 B-R1	+0.929 B-R1	104.3 B-P	31.248 B-P	32.888 B-P	50.207 B-P
11	Mazda MX-5	Gavin Wardle	STL	169	1:54.845 A-R1	sector data unreliable	1:58.292 A-Q2	1:54.845 A-R1	1:59.598 A-R2	+0.868 A-R2	132.7 A-R2	8.264	33.984	51.822
12	Mazda Miata	Nick Leverone	STL	137, 37	1:54.963 B-Q2	1:54.891	1:54.963 B-Q2	1:55.682 B-R1	1:56.512 B-R1	+1.038 B-R1	106.0 B-Q1	31.458 B-Q2	32.979 B-Q2	50.454 B-Q2
13	Ford Mustang	Roger Eagleton	AS	11	1:55.849 B-R1	1:55.569	1:56.445 B-Q1	1:55.849 B-R1	1:56.324 B-R1	+0.678 B-R1	108.7 B-R1	31.659 B-Q1	33.571 B-R1	50.339 B-R1
14	Ford Mustang	Ross Murray	AS	14, 74	1:56.314 A-R1	1:56.047	1:56.812 A-Q1	1:56.314 A-R1	1:56.660 A-R1	+0.887 A-R1	135.2 A-R2	32.070 A-R1	33.689 A-R1	50.288 A-R1
15	Honda Civic Si	Jonathan Lugod	STL	61	1:56.438 B-R1	1:56.128	1:57.331 B-Q2	1:56.438 B-R1	1:57.403 B-R1	+1.528 B-R1	106.8 B-P	31.787 B-P	33.468 B-P	50.873 B-P
16	BMW 330	Sean Lovett	STU	37	1:56.492 A-Q2	1:56.426	1:56.492 A-Q2	1:57.049 A-R2	1:57.605 A-R2	+1.649 A-R2	133.7 A-R2	31.816 A-Q2	33.669 A-Q1	50.941 A-Q2
17	Honda Prelude	Carl Young	STL	23	1:56.961 B-R1	1:56.631	1:57.917 B-Q2	1:56.961 B-R1	1:57.759 B-R1	+1.599 B-R1	104.5 B-Q2	31.994 B-R1	33.745 B-R1	50.892 B-R1
18	Mazda MX-5	Ryan Gutile	STL	116	1:57.404 B-Q1	1:57.004	1:57.404 B-Q1	1:57.483 B-R1	1:58.542 B-R1	+1.371 B-R1	128.4 A-Q2	31.829 B-R1	33.695 B-Q1	51.480 B-R1
19	Mazda Miata	Amy Mills	STL	114	1:57.757 A-Q2	1:57.494	1:57.757 A-Q2	1:58.239 B-R2	1:58.840 B-R2	+1.462 B-R2	122.6 A-R2	32.321 B-Q2	33.780 A-Q2	51.393 A-Q2
20	Mazda MX-5	Bryce Johnson	STL	15, 13	1:58.716 A-Q2	1:58.419	1:58.716 A-Q2	1:59.496 A-R2	1:59.874 A-R2	+0.878 A-R2	136.6 A-Q1	32.248 A-Q1	34.104 A-Q2	52.067 A-Q2
21	Ford Mustang FR500S	Pratt Cole	AS	8, 8x	1:58.795 B-R1	1:58.078	1:59.911 B-Q1	1:58.795 B-R1	1:59.396 B-R1	+1.547 B-R1	103.3 B-Q1	32.531 B-R1	33.997 B-R1	51.550 B-R1
22	Ford Mustang	Matt Lituchy	AS	30	1:59.134 B-R1	1:58.732	2:00.395 B-Q1	1:59.134 B-R1	1:59.643 B-R1	+0.914 B-R1	105.1 B-Q1	32.777 B-R1	34.259 B-R1	51.696 B-R2
23	Nissan 300ZX	James Slechta	STU	75	1:59.183 A-Q2	1:59.183	1:59.183 A-Q2	2:00.458 A-R2	2:01.009 A-R2	+0.921 A-R2	132.0 A-Q1	32.882 A-Q2	34.528 A-Q2	51.773 A-Q2
24	Mazda Miata	Patrick Drinkwine	STL	151	1:59.239 B-Q1	1:58.754	1:59.239 B-Q1	2:00.132 B-R1	2:00.548 B-R1	+0.505 B-R1	106.6 B-P	32.503 B-P	34.167 B-P	52.084 B-P
25	Mazda MX-5	Oscar Jackson	STU	161	1:59.707 B-R2	1:58.888		1:59.707 B-R2	1:59.952 B-R2	+1.112 B-R2	103.9 B-R2	32.339 B-R2	34.219 B-R2	52.330 B-R2
26	Mazda MX-5 (2015)	Adrian Comstock	STL	25	2:00.239 A-Q2	2:00.015	2:00.239 A-Q2	2:00.722 A-R1	2:01.250 A-R2	+0.672 A-R2	133.0 A-R2	32.847 A-R2	34.493 A-Q2	52.675 A-Q2
27	Mazda RX-7	Michael Lewis	STU	32	2:00.248 A-R1	2:00.179		2:00.248 A-R1	2:02.190 A-R2	+1.431 A-R2	130.4 A-R1	32.729 A-R1	34.570 A-R1	52.880 A-R1
28	Mazda MX-5	Andy Chittum	STL	99	2:00.296 A-Q2	1:59.684	2:00.296 A-Q2	2:00.787 A-R1	2:01.366 A-R1	+1.093 A-R1	132.9 A-R2	32.848 A-Q1	34.467 A-Q2	52.369 A-Q2
29	Ford Mustang	Michael Lowe	AS	10	2:00.612 A-R2	2:00.126	2:03.053 A-Q1	2:00.612 A-R2	2:02.546 A-R2	+4.568 A-R2	126.5 A-R1	32.652 B-R1	34.913 B-R1	52.561 A-R2
30	Mazda MX-5	Dale Shoemaker	STU	52	2:01.642 B-R2	2:01.176	2:04.115 B-Q1	2:01.642 B-R2	2:02.793 B-R2	+2.442 B-R2	125.9 A-Q2	32.956 B-R2	34.983 B-R2	53.237 B-R2
31	Mazda Miata	Richard James	STL	191, 91	2:02.318 B-R1	2:01.786	2:02.441 A-Q1	2:02.318 B-R1	2:03.149 B-R2	+0.867 B-R2	126.7 A-R1	32.990 B-R1	35.132 A-Q1	53.664 B-R1
32	Mazda Miata	Todd Launchbaugh	STL	73	2:02.759 B-R1	2:02.624		2:02.759 B-R1	2:03.974 B-R1	+1.599 B-R1	98.5 B-R1	33.210 B-R1	35.059 B-R1	54.355 B-R1
33	Mazda Miata	Ayden Vaillancour	STL	88	2:03.022 B-R1	2:02.301	2:03.653 B-Q2	2:03.022 B-R1	2:03.841 B-R1	+0.936 B-R1	100.4 B-P	33.072 B-P	35.168 B-P	54.061 B-R1
34	Mazda Miata	Lauren Lewis >115%	STL	45	2:17.307 A-R1	2:16.162		2:17.307 A-R1	2:18.705 A-R1	+1.938 A-R1	108.6 A-R1	36.821 A-R1	39.026 A-R1	1:00.315 A-R2
35	Acura integra	Jack McEachern >115%	STL	21	2:24.310 B-Q2	2:22.511	2:24.310 B-Q2	2:24.550 B-R2	2:32.162 B-R1	+2.229 B-R1	77.6 B-Q1	38.960 B-Q1	41.141 B-Q2	1:02.410 B-R2

One row per driver and car (a driver who changed cars has a row for each). Each cell is that driver's best in that car across the selected events, with the session it was set in. Best 5-lap stint is the mean of the driver's quickest five consecutive race laps, and consistency is how far their median race lap sat behind their best in that race (small is a driver who does it every lap); both come from the race with the best stint. The fastest in each column is purple, and a car whose best lap is more than 115% of the fastest in its class is greyed (marked ">115%" beside the driver) and left out of the colour scale. Click a column to sort, a row to highlight it. Theoretical lap is the sum of the best sectors, whichever laps they came from, and never slower than the best lap (where a car's fastest laps were recorded without sector times, its best lap is used). The 115% mark is about the car's best lap only: a car whose best lap is within 115% of the fastest in its class is never marked. Greyed sectors with no theoretical lap mean the sector times on file do not add up to a believable lap. Letters refer to the events above; Q is qualifying, R a race.

Sectors

S1 SF → IM1 0.65 mi
S2 IM1 → IM2 0.75 mi
S3 IM2 → SF 1.17 mi
Spd In → Out 0.03 mi

Sectors are numbered in lap order from start/finish, whatever each event's timing called them; the loop names are SCCA timing's.

By car

Car	Class	Drivers	Lap	Qual	Race	Trap	S1	S2	S3
Mazda RX-3	STU	1	1:50.913Tony Rivera	1:50.913Tony Rivera	1:52.737Tony Rivera	135.2Tony Rivera	30.415Tony Rivera	32.456Tony Rivera	47.999Tony Rivera
Mazda Miata	STL/STU	20	1:51.602Whitfield Gregg	1:54.963Nick Leverone	1:54.845Gavin Wardle	136.6Bryce Johnson	8.264Gavin Wardle	32.218Jared Korth	48.687Whitfield Gregg
Mazda Miata	STL/STU	11	1:51.602Whitfield Gregg	1:54.963Nick Leverone	1:55.682Nick Leverone	133.4Wesley Mollno	30.652Whitfield Gregg	32.263Whitfield Gregg	48.687Whitfield Gregg
Mazda MX-5	STL/STU	8	1:51.665Jared Korth	1:57.404Ryan Gutile	1:54.845Gavin Wardle	136.6Bryce Johnson	8.264Gavin Wardle	32.218Jared Korth	48.811Jared Korth
Mazda MX-5 (2015)	STL	1	2:00.239Adrian Comstock	2:00.239Adrian Comstock	2:00.722Adrian Comstock	133.0Adrian Comstock	32.847Adrian Comstock	34.493Adrian Comstock	52.675Adrian Comstock
BMW M3	STU	1	1:52.380Wilson Powell	1:55.401Wilson Powell	1:53.843Wilson Powell	102.6Wilson Powell	30.577Wilson Powell	32.372Wilson Powell	49.215Wilson Powell
Mazda RX-8	STL	1	1:53.515David LeCren	2:09.464David LeCren	2:11.372David LeCren	121.0David LeCren	31.217David LeCren	32.486David LeCren	49.550David LeCren
Honda S2000	STU	1	1:53.640Rylan Hazelton	1:55.834Rylan Hazelton	1:53.640Rylan Hazelton	134.8Rylan Hazelton	30.582Rylan Hazelton	32.779Rylan Hazelton	49.779Rylan Hazelton
Ford Mustang	AS	5	1:55.849Roger Eagleton	1:56.445Roger Eagleton	1:55.849Roger Eagleton	135.2Ross Murray	31.659Roger Eagleton	33.571Roger Eagleton	50.288Ross Murray
Ford Mustang	AS	4	1:55.849Roger Eagleton	1:56.445Roger Eagleton	1:55.849Roger Eagleton	135.2Ross Murray	31.659Roger Eagleton	33.571Roger Eagleton	50.288Ross Murray
Ford Mustang FR500S	AS	1	1:58.795Pratt Cole	1:59.911Pratt Cole	1:58.795Pratt Cole	103.3Pratt Cole	32.531Pratt Cole	33.997Pratt Cole	51.550Pratt Cole
Honda Civic Si	STL	1	1:56.438Jonathan Lugod	1:57.331Jonathan Lugod	1:56.438Jonathan Lugod	106.8Jonathan Lugod	31.787Jonathan Lugod	33.468Jonathan Lugod	50.873Jonathan Lugod
BMW 330	STU	1	1:56.492Sean Lovett	1:56.492Sean Lovett	1:57.049Sean Lovett	133.7Sean Lovett	31.816Sean Lovett	33.669Sean Lovett	50.941Sean Lovett
Honda Prelude	STL	1	1:56.961Carl Young	1:57.917Carl Young	1:56.961Carl Young	104.5Carl Young	31.994Carl Young	33.745Carl Young	50.892Carl Young
Nissan 300ZX	STU	1	1:59.183James Slechta	1:59.183James Slechta	2:00.458James Slechta	132.0James Slechta	32.882James Slechta	34.528James Slechta	51.773James Slechta
Mazda RX-7	STU	1	2:00.248Michael Lewis		2:00.248Michael Lewis	130.4Michael Lewis	32.729Michael Lewis	34.570Michael Lewis	52.880Michael Lewis
Acura integra	STL	1	2:24.310Jack McEachern	2:24.310Jack McEachern	2:24.550Jack McEachern	77.6Jack McEachern	38.960Jack McEachern	41.141Jack McEachern	1:02.410Jack McEachern

The best any driver of each car managed across the selected events, with who set it. Spellings and model years of the same car are grouped; click a row marked ▸ to see each version. Grouping is worked out from the names, so tell us if two cars are wrongly merged or split.

Rule changes between these events

Cal Club 2023 → Cal Club 2024 2023-02-24 to 2024-02-23

2023-03-01 STU E&O STU NA Weight Chart.

#33737 from Eric Heinrich · Rule change · TB 23-03 (2023-03 Fastrack)

Summary

fasterSTU minimum weight chart updated: 2450cc to 2595lbs, 2600cc to 2710lbs.

As printed in Fastrack

In STU, GCR Section 9.1.4.1.H.1. chart, Factory Engine Displacement (cc) Minimum Weight (lbs), change as follows:
"2450 ~~2596~~ 2595"
"2600 ~~2860~~ 2710"

2023-04-01 STU Alternate OEM Miata Intake Manifold

#33827 from Brandon Steinhauer · Rule change · TB 23-04 (2023-04 Fastrack)

Summary

wordingSTU Mazda BP5A classified at 1839 cc maximum displacement, 2023-04-01.

As printed in Fastrack

In STU Spec lines, classify Mazda BP5A as follows:
STU Maximum Displacement (cc's) Minimum Weight Notes
Mazda BP5A 1839 Chart May use engine in its entirety or specific
components from the engine.

2023-06-01 STL Clarify STL table B - IT spec notes on Tires

#34187 from Austin Hilliard · Rule change · TB 23-06 (2023-05 Fastrack)

Summary

wordingSTL ITA/ITS RX7 and 1985+ ITA/ITS/ITB/ITC vehicles clarified to conform to section 9.1.4.2 tire specifications.

As printed in Fastrack

In STL Spec Lines, Table B: Alternate Vehicle and Engine Allowances, change Notes as follows:
ITA-spec and ITS-spec RX7: "Must completely conform to ITCS specifications. Tires must conform to 9.1.4, Tires & Wheels. Tires
must also conform to 9.1.4.2.Tires."
ITS, ITA, ITB, or ITC vehicles (1985- ): "Must completely conform to ITCS specifications. Tires must conform to 9.1.4, Tires &
Wheels. Tires must also conform to 9.1.4.2.Tires."

2023-07-01 STU 2022 Toyota GR Cup for STU

#34449 from Club Racing Board · Rule change · TB 23-06 (2023-05 Fastrack)

Summary

cars addedToyota GR Cup and GR86 Cup (2022-) newly classified in STU at 2700 lbs with 2387 cc engine.

As printed in Fastrack

In STU Spec Lines, Toyota GR Cup (2022-), classify as follows:

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

2023-08-01 AS Crate Motor Part Numbers

#32944 from Sam Daniels · Rule change · TB 23-08 (2023-08 Fastrack)

Summary

wordingAS crate motor part number specified: GM Performance CT400 P/N 19370604 engine assembly for GM vehicles.

As printed in Fastrack

In AS, GCR Section 9.1.6.F.2., change as follows:
"GM Performance parts CT400 P/N-1937 → 0604 or 1937 → 0604 engine assembly for GM produced vehicles."

2023-08-01 AS Request wheel size change

#33007 from Michael Kamalian · Rule change · TB 23-08 (2023-08 Fastrack)

Summary

fasterAS Spec Lines Ford Mustang GT 5.0L (15-17) max wheel size increases to 19.0 inches.

As printed in Fastrack

In AS Spec Lines, Ford Mustang GT 5.0l (15-17) Restricted Preparation, change Notes as follows:
"Max. Wheel Size: Dia.~~18.0~~ 19.0 inches."

Applies to Ford Mustang on this page: Roger Eagleton, Ross Murray, Matt Lituchy, Michael Lowe, Pratt Cole

2023-08-01 AS Alternative Upper Front Control Arms for Dodge Challenger

#33352 from Clark Cambern · Rule change · TB 23-08 (2023-08 Fastrack)

Summary

wordingAS Dodge Challenger 5.7L/6.1L/6.4L V8 now permits SPC-66045 alternate front upper control arms.

As printed in Fastrack

In AS SPEC Lines, Dodge Challenger (08-20) Restricted Preparation 5.7L, 6.1L, or 6.4L V8 (Iron block, Aluminum heads), 2
valves/cylinder, change Notes as follows:
"~~SPC-66045~~ Alternate front upper control arms are permitted."

2023-08-01 AS Front Brake Caliper Adapters for Dodge Challenger

#33353 from Clark Cambern · Rule change · TB 23-08 (2023-08 Fastrack)

Summary

wordingAS Dodge Challenger 5.7L/6.1L/6.4L V8 allows alternate front brake caliper adapters for updated or backdated components.

As printed in Fastrack

In AS SPEC Lines, Dodge Challenger (08-20) Restricted Preparation 5.7L, 6.1L, or 6.4L V8 (Iron block, Aluminum heads), 2
valves/cylinder, change Notes as follows:
"Stock brakes or alternate Dodge brakes (Part numbers: front caliper (0517 → 5106 (R) and 0517 → 5107 (L); rear caliper (R1542564 (R)
and R1542565 (L))) may be used with the brake rotor sizes listed in this specification line. Alternate brackets may be used to
facilitate updated/backdated components."

2024-01-01 STL Alternate Carburetor Request for 79-85 RX7 12a

#35181 from Dan Sheppard · Rule change · TB 24-01 (2024-01 Fastrack)

Summary

unclearSTL Mazda RX-7 12A (79-85) now allows auto-type 2 bbl with 42mm choke(s) on dual-y manifold as alternate to stock Nikki 4 bbl.

As printed in Fastrack

In STL Table B: Alternate Vehicle and Engine Allowances, Mazda RX-7 12A (79-85), change Notes as follows:
"Street Porting of the engine only. Bridge porting, peripheral porting, and eyelash porting are prohibited. Contact SCCA National
Office for details of Street porting. Stock Nikki 4 bbl carburetor on a stock manifold ~~only.~~ or auto-type 2 bbl w/42mm choke(s) on
a “dual-y” manifold. Allow the standard removal of emissions related components, and allow air and fuel jets to be corrected.
Modification of the water jacket in the area of the spark plug for cooling purposes is permitted."

2024-02-01 STU ST Electric-Assisted Steering Systems

#35066 from Jose Osiris Pena · Rule change · TB 24-02 (2024-01 Fastrack)

Summary

wordingSTL and STU power steering rules clarified to permit electric-assisted and hydraulic-assisted steering systems.

As printed in Fastrack

In GCR, Section 9.1.4.M.16., change as follows:
"Power steering may be modified in any of the following ways:
a. disconnected , pump, belt, pulley, and hoses may be removed. Hoses may also be looped. Steering rack or box may be
modified internally to work without pump.
b. an OEM manual steering rack for that model may be fitted
c. an electric power steering pump may be fitted
d. an OEM electric-assisted steering system may be used or any column mounted electric steering assist may be used
e. an OEM hydraulic-assisted steering system may be used"

2024-02-01 STL ST Electric-Assisted Steering Systems

#35066 from Jose Osiris Pena · Rule change · TB 24-02 (2024-01 Fastrack)

Summary

wordingSTL and STU power steering rules clarified to permit electric-assisted and hydraulic-assisted steering systems.

As printed in Fastrack

2024-02-01 STL BOP Adjustments

#35112 from Super Touring Committee · Rule change · TB 24-02 (2024-01 Fastrack)

Summary

fasterSTL Acura/Honda B-series and Mazda MZR restrictors reduced 2mm; minimum weights down 25–75 lbs for 1900–2000cc engines.

As printed in Fastrack

In GCR, 9.1.4.H.1., change as follows:
"Minimum weights for cars with normally aspirated piston engines will be determined by ~~1.35 lbs/cc displacement for~~
~~the installed engine (see~~ the following table). Displacement is the factory displacement for the installed engine. For the
purpose of weight assignment, engine displacement will be rounded to the nearest 50cc (e.g., 2176cc = 2200cc and
2175cc = 2150cc)."
In GCR, 9.1.4.H.1., change Minimum Weight on Chart as follows:
Factory Engine Displacement 1900: "Effective 3-1-24: ~~2565~~ 2540"
Factory Engine Displacement 1950: "Effective 3-1-24: ~~2633~~ 2583"

Show 11 more lines

Factory Engine Displacement 2000: "Effective 3-1-24: ~~2700~~ 2625"
In GCR, 9.1.4.H.3., change as follows:
"Front wheel drive cars with a strut type front suspension may reduce their minimum weight by 2.5 percent. Effective 3-
1-24: Front wheel drive cars with 95" or less wheelbase must add 1.25% to their minimum weight."
In STL Spec Lines, change Notes as follows:
Acura/Honda B16: "Effective 3-1-24: 53 51mm"
Acura/Honda B17: "Effective 3-1-24: 53 51mm"
Acura/Honda B18C1: "Effective 3-1-24: 53 51mm"
Acura/Honda B18C (JDM Type R), B18C5 (USDM Type R), B18C6 (UK and Euro Type R), B18C7 (Australia Type R):
"Effective 3-1-24:52 50mm"
Mazda MZR: "Effective 3-1-24: 52 50mm"

2024-02-01 STL Mazda 12A

#35320 from Super Touring Committee · Rule change · TB 24-02 (2024-02 Fastrack)

Summary

slowerSTL Mazda 12A must keep 5th and 6th intake port actuators and valves, no longer allowed removal or disabling.

As printed in Fastrack

In STL Spec Lines, Table A, Mazda 12A, change Notes as follows:
"~~The 5th and 6th intake port actuators and valves may be removed or disabled.~~"

Cal Club 2024 → Cal Club 2025 2024-02-23 to 2025-02-22

2024-03-01 AS Request to Classify 1970-1981 Camaro and Firebird in AS

#33659 from Brandon Vivian · Rule change · TB 24-03 (2024-03 Fastrack)

Summary

cars addedChevrolet Camaro, Pontiac Firebird 70-81 Full Prep classified AS at 3400-3600 lbs with 250 lb weight reduction.

As printed in Fastrack

In AS Spec Lines, classify Chevrolet Camaro, Pontiac Firebird (70-81) Full Prep as follows:
AS Wheelbase Gear Ratios
Std. (or Alt.)
Brakes
(Max)
(in/mm)
Weight (lbs) Notes:

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

2024-03-01 AS Fuel Cell 12

#34194 from Clark Cambern · Rule change · TB 24-03 (2024-03 Fastrack)

Summary

wordingAS class: multiple cars gain fuel cell placement note allowing 24 inches from standard tank, unrestricted filler location.

As printed in Fastrack

In AS Spec Lines, add to Notes as follows:
Cadillac CTS-V (04-07): “Fuel cells must be located within 24 inches of the standard tank. The 24 inch measurement is taken
from the perimeter of the stock and alternative fuel cell. Fuel filler location is unrestricted with installation of a safety fuel cell.”
Chevrolet/Pontiac Camaro & Firebird (93-02): “Fuel cells must be located within 24 inches of the standard tank. The 24 inch
measurement is taken from the perimeter of the stock and alternative fuel cell. Fuel filler location is unrestricted with
installation of a safety fuel cell.”
Chevrolet/Pontiac Camaro & Firebird (93-02): “Fuel cells must be located within 24 inches of the standard tank. The 24
inch measurement is taken from the perimeter of the stock and alternative fuel cell. Fuel filler location is unrestricted with

Show 22 more lines

installation of a safety fuel cell.”
Chevrolet Camaro SS (V8) (10-15): “Fuel cells must be located within 24 inches of the standard tank. The 24 inch
measurement is taken from the perimeter of the stock and alternative fuel cell. Fuel filler location is unrestricted with
installation of a safety fuel cell.”
Chevrolet Camaro (10-15): “Fuel cells must be located within 24 inches of the standard tank. The 24 inch measurement is
taken from the perimeter of the stock and alternative fuel cell. Fuel filler location is unrestricted with installation of a
safety fuel cell.”
Dodge Challenger (08-20): “Fuel cells must be located within 24 inches of the standard tank. The 24 inch measurement is
taken from the perimeter of the stock and alternative fuel cell. Fuel filler location is unrestricted with installation of a
safety fuel cell.”
Ford Mustang GT (05-14): “Fuel cells must be located within 24 inches of the standard tank. The 24 inch measurement is
taken from the perimeter of the stock and alternative fuel cell. Fuel filler location is unrestricted with installation of a
safety fuel cell.”
Ford Mustang Coupe GT (05-14): “Fuel cells must be located within 24 inches of the standard tank. The 24 inch
measurement is taken from the perimeter of the stock and alternative fuel cell. Fuel filler location is unrestricted with
installation of a safety fuel cell.”
Ford Mustang GT 5.0l (15-17): “Fuel cells must be located within 24 inches of the standard tank. The 24 inch measurement
is taken from the perimeter of the stock and alternative fuel cell. Fuel filler location is unrestricted with installation of a
safety fuel cell.”
Ford Mustang GT (05-14): “Fuel cells must be located within 24 inches of the standard tank. The 24 inch measurement is
taken from the perimeter of the stock and alternative fuel cell. Fuel filler location is unrestricted with installation of a
safety fuel cell.”

2024-03-01 AS Please Classify the 6th Gen Into AS.

#35448 from Daniel Richardson · Rule change · TB 24-03 (2024-03 Fastrack)

Summary

cars addedChevrolet Camaro 16- Full Prep classified into AS at 3400 lbs with 250 lb weight reduction.

As printed in Fastrack

In AS Spec Lines, classify Chevrolet Camaro (16-) Full Prep as follows:
AS
Wheelbase Gear Ratios
Std. (or Alt.)
Brakes
(Max)
(in/mm)
Weight (lbs) Notes:

Show 4 more lines

Chevrolet
Camaro (16-)
Full Prep
110.6 3.42, 2.28,

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

2024-03-01 STU Letter #35397 addendum

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

Summary

wordingSTU Mini Cooper S SC: alternate LEAP OMICRON hood scoop LEP-OMICRON3 permitted.

As printed in 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)

Summary

wordingSTU BMW S54 B32 OEM now permits dry sump oiling system.

As printed in Fastrack

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

2024-03-01 AS spec lines

#35713 from American Sedan Committee · Rule change · TB 24-03 (2024-03 Fastrack)

Summary

cars addedAS adds Ford Mustang GT 05-14 Restricted prep Engine with 62mm FPR, 3400 lbs minimum, 18-inch wheels.

As printed in Fastrack

In AS Spec Lines, classify Ford Mustang GT (05-14) with Restricted prep Engine as follows:
AS
Wheelbase Gear Ratios Std.

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

Applies to Ford Mustang on this page: Roger Eagleton, Ross Murray, Matt Lituchy, Michael Lowe, Pratt Cole

2024-04-01 AS Restricted Prep Aftermarket Parts Request

#35682 from Tom Aquilante · Rule change · TB 24-04 (2024-04 Fastrack)

Summary

wordingAS Camaro/Firebird and GTO LS1 connecting rods approved: Callies CSC6100DS6A2AH, Scat 2-1CR6100-944, GM 12649190.

As printed in Fastrack

In AS Spec Lines, Chevrolet/Pontiac Camaro & Firebird (93-02), add to Notes the following:
"For the LS1connecting rods Callies p/n CSC6100DS6A2AH, Scat rods p/n 2-1CR6100-944, GM performance rods p/n 12649190."
In AS Spec Lines, Pontiac GTO (04-06), add to Notes the following:
"For the LS1connecting rods Callies p/n CSC6100DS6A2AH, Scat rods p/n 2-1CR6100-944, GM performance rods p/n 12649190."

2024-04-01 AS Allowance of 11

#35824 from American Sedan Committee · Rule change · TB 24-04 (2024-04 Fastrack)

Summary

fasterAS Cadillac CTS-V, Chevrolet Camaro SS, Dodge Challenger, Ford Mustang GT, Pontiac GTO allowed 11" wheels until 3/1/25.

As printed in Fastrack

In AS Spec Lines, Cadillac CTS-V (04-07), add to Notes the following:
"11" wide wheels can be used until 3/1/25."
In AS Spec Lines, Chevrolet Camaro SS (V8) (10-15), add to Notes the following:
"11" wide wheels can be used until 3/1/25."
In AS Spec Lines, Dodge Challenger (08-20), add to Notes the following:
"11" wide wheels can be used until 3/1/25."
In AS Spec Lines, Ford Mustang GT 5.0l (15-17), add to Notes the following:
"11" wide wheels can be used until 3/1/25."

Show 2 more lines

In AS Spec Lines, Pontiac GTO (04-06), add to Notes the following:
"11" wide wheels can be used until 3/1/25."

Applies to Ford Mustang on this page: Roger Eagleton, Ross Murray, Matt Lituchy, Michael Lowe, Pratt Cole

2024-05-01 AS 6th gen Camaro limited prep

#35733 from American Sedan Committee · Rule change · TB 24-05 (2024-05 Fastrack)

Summary

cars addedAS Chevrolet Camaro 1LE (2016-) classified with 3600 lbs minimum weight, 60mm restrictor, 275 tires.

As printed in Fastrack

In AS Spec Lines, classify Chevrolet Camaro 1LE (2016-) as follows:
AS Wheelbase Gear Ratios Std. (or Alt.)
Brakes
(Max)
(in/mm)
Weight (lbs.) Notes:
Chevrolet
Camaro, 1LE

Show 2 more lines

(2016-)
110.6 2.66,1.78,1.30,0.74,.5 (F)

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

2024-05-01 AS Chevrolet/Pontiac Camaro & Firebird (82-92) 5.7L V8 LS1 Alum BLK

#35825 from Desi Colon · Rule change · TB 24-05 (2024-05 Fastrack)

Summary

cars addedAS Chevrolet/Pontiac Camaro & Firebird 82-92 5.7L LS1 classified at 3200 lbs with 65mm restrictor plate required.

As printed in Fastrack

In AS Spec Lines, classify Chevrolet/Pontiac Camaro & Firebird (82-92) 5.7L V-8 LS1 (Aluminum Block, Aluminum Heads) 2 valves
per cylinder, as follows:
AS Wheelbase Gear Ratios Std.

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

2024-05-01 AS Full Prep Head

#35891 from American Sedan Committee · Rule change · TB 24-05 (2024-05 Fastrack)

Summary

otherAS Chevrolet Camaro, Firebird, and Ford Mustang models permitted to use Flo Tek cylinder heads.

As printed in Fastrack

In AS Spec Lines, Chevrolet/Pontiac Camaro & Firebird (82-92), add to Notes the following:
"Flo Tek Head part #102-500 are permitted."
In AS Spec Lines, Chevrolet/Pontiac Camaro & Firebird (93-02), add to Notes the following:
"Flo Tek Head part #102-500 are permitted."
In AS Spec Lines, Chevrolet Camaro (10-15), add to Notes the following:
"Flo Tek Head part #102-500 are permitted."
In AS Spec Lines, Ford Mustang Incl. Cobra & Cobra R (79-93) and Mercury Capri (79-86), add to Notes the following:
"Flo Tek Part # 203-500 are permitted."

Show 4 more lines

In AS Spec Lines, Ford Mustang Including Cobra 94-04, add to Notes the following:
"Flo Tek Part # 203-500 are permitted."
In AS Spec Lines, Ford Mustang GT (05-14), add to Notes the following:
"Flo Tek Part # 203-500 are permitted."

Applies to Ford Mustang on this page: Roger Eagleton, Ross Murray, Matt Lituchy, Michael Lowe, Pratt Cole

2024-06-01 AS Request for Classification of 2018-2023 mustang In

#35764 from Michael Kamalian · Rule change · TB 24-06 (2024-06 Fastrack)

Summary

cars addedAS Ford Mustang GT 5.0L (2018-) classified at 3600 lbs with 60mm restrictor, Brembo BBK permitted.

As printed in Fastrack

AS Spec Lines, classify Ford Mustang GT 5.0L (2018-) as follows:
AS Wheelbase Gear Ratios

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

2024-08-01 STU RWD Turbo Disadvantage

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

Summary

fasterSTU RWD turbo cars no longer required to reduce restrictor by 1 mm from table.

As printed in 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~~"

2024-09-01 AS Mustang transmission ratios

#36662 from American Sedan Committee · Rule change · TB 24-09 (2024-09 Fastrack)

Summary

unclearAS Ford Mustang GT models gain alternate transmission ratio options for 2024-09-01.

As printed in Fastrack

In AS Spec Lines, Ford Mustang GT (05-14) with Restricted Prep Engine, add to Notes as follows:
"Alternate transmission Ratios 3.66, 2.43, 1.69, 1.32, 1.00, .68.”
In AS Spec Lines, Ford Mustang GT 5.0L (2018-), add to Notes as follows:
"Alternate transmission Ratios 3.24, 2.10, 1.42, 1.00, 0.81, .062."

Applies to Ford Mustang on this page: Roger Eagleton, Ross Murray, Matt Lituchy, Michael Lowe, Pratt Cole

2024-11-01 STU R53 15% Pulley Request

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

Summary

slowerSTU Mini Cooper S SC 1900 restricts to 2.565 diameter pulley; 2100 allows 2.285 diameter pulley.

As printed in 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 STU Request to Remove Miata Hubs from General category

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

Summary

wordingSTL/STU: 90-05 Mazda Miata alternate front wheel hubs moved from General to specific part approval.

As printed in 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 STL Request to Remove Miata Hubs from General category

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

Summary

wordingSTL/STU: 90-05 Mazda Miata alternate front wheel hubs moved from General to specific part approval.

As printed in Fastrack

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

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

Summary

slowerSTU BMW N54/N55 turbo inlet restrictors now required per GCR definition; turbo swapping prohibited.

As printed in 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 AS Increase Coyote Engine Restrictor to 80mm

#36177 from Gregory Eaton · Rule change · TB 25-01 (2025-01 Fastrack)

Summary

fasterAS Ford Mustang Coyote engines increase restrictor to 80mm from 64mm or 67mm.

As printed in Fastrack

In AS Spec Lines, add to Notes as follows:
Ford mustang (GT 05-14): "Gen 1- 67mm Gen 2-64mm"
Ford mustang (GT 05-14): "Gen 1- 67mm"
Ford mustang (GT 15-17): "Gen 1- 67mm"
Ford mustang (GT 94-04): "Gen 1- 67mm Gen 2-64mm"
Ford mustang cobra & Cobra R Mercury Capri (79-93) (79-86): "Gen 1- 67mm Gen 2-64mm"

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

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

Summary

fasterSTU Audi 1.8T wagon deleted; Porsche 944 1800 weight to Chart, turbo inlet restrictor removed.

As printed in 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 permitted~~inlet restrictor required~~."

2025-01-01 AS Performance Pack for 2015+ Mustang

#36867 from Michael Kamalian · Rule change · TB 25-01 (2025-01 Fastrack)

Summary

fasterAS Mustang GT 05-14 4.6L loses 300 lbs; 15-17 and 2018+ models lose 61mm and 60mm restrictors respectively.

As printed in Fastrack

In AS Spec Lines, Ford Mustang Coupe GT (05-14) Restricted Prep., change Notes as follows:
"The 4.6L engine assembly has a weight reduction of 300 lbs. 5.0L/6spd engine/trans: track pack front and rear spoiler allowed."
In AS Spec Lines, Ford Mustang Coupe GT (05-14) with Restricted Prep. engine, change Notes as follows:
"Max. Wheel Size: Dia.18.0 inches. Stock brakes or alternate Ford 14” Brembo Brake (Ford Racing Kit #M-2300-S) and full prep
brake package may be used. Either engine may be used. ~~1st Generation 5.0l Coyote 11-14 62mm FPR 2nd Generation 5.0l~~
~~Coyote 15-17 61mm FPR~~ Cold Air Intake allowed Charge Motion Control Valves can be blocked off and removed for firewall
clearance Allow Cold Air Intake Tremec Magnum transmission may be used P/N- TUKT16901. Full Prep Transmissions rule
package may also be used. Max compression ratio, 11.2:1 track pack front and rear spoiler allowed. Alternate transmission

Show 10 more lines

Ratios 3.66, 2.43, 1.69, 1.32, 1.00, .68."
In AS Spec Lines, Ford Mustang GT 5.0l (15-17) Restricted Preparation, change Notes as follows:
"Max. Wheel Size: Dia. 18.0 inches. Stock brakes or alternate Ford Brembo Brake caliper (Ford Racing Kit #M-2300-S) may be
used. ~~61mm flat plate restrictor required. Fuel cells must be located within 24 inches of the standard tank. The 24 inch~~
~~measurement is taken from the perimeter of the stock and alternative fuel cell. Fuel filler location is unrestricted with installation~~
~~of a safety fuel cell~~. 11” wide wheels can be used until 3/1/25. Performance pack front and rear spoiler, body kit allowed."
In AS Spec Lines, Ford Mustang GT 5.0L (2018-), change Notes as follows:
"Package Brembo front BBK and 380mm rotors permitted (Ford PN M-2300-V) at no weight penalty. ~~60mm flat plate restrictor~~
~~required.~~ 2014 Mustang GT exhaust manifolds permitted. Ford Racing oil pan #M-6675-M50BR permitted. ~~Alternate~~
~~transmission Ratios 3.24, 2.10, 1.42, 1.00, 0.81, .062.~~ Performance pack front and rear spoiler, body kit allowed."

Applies to Ford Mustang on this page: Roger Eagleton, Ross Murray, Matt Lituchy, Michael Lowe, Pratt Cole

2025-01-01 AS Gear Ratios

#37131 from Timothy White · Rule change · TB 25-01 (2025-01 Fastrack)

Summary

wordingAS class gear ratio options specified for multiple American muscle cars, including Cadillac CTS-V, Chevrolet Camaro, Ford Mustang, Dodge Challenger, and Pontiac GTO.

As printed in Fastrack

In AS Spec Lines, change Gear Ratios as follows:
Cadillac CTS-V (04-07):
"2.97, 2.07, 1.43,1.00, 0.84,0.56 or 3.01, 2.07, 1.43, 1.0, .84, .57 or 2.20, 1.64,1.28,1.00 or 2.88, 1.91, 1.33, 1.00"
Chevrolet Camaro, Pontiac Firebird (70-81), Full Prep:
"3.42, 2.28, 1.45, 1.00 or 2.95, 1.94, 1.34, 1.00, 0.73 or 3.35, 1.93, 1.29, 1.00, 0.61, or 2.20, 1.64,1.28,1.00 or 2.87,1.89,1.28,1.00"
Chevrolet Camaro, Pontiac Firebird (70-81), Restricted Prep.:
"3.42, 2.28, 1.45, 1.00 or 2.95, 1.94, 1.34, 1.00, 0.73 or 3.35, 1.93, 1.29, 1.00, 0.61, or 2.20, 1.64,1.28,1.00 or 2.87,1.89,1.28,1.00"
Chevrolet/Pontiac Camaro & Firebird (82-92) Full Prep:

Show 42 more lines

"3.42, 2.28, 1.45, 1.00 or 2.95, 1.94, 1.34, 1.00, 0.73 or 3.35, 1.93, 1.29, 1.00, 0.61 or 2.20, 1.64,1.28,1.00 or 2.88, 1.91, 1.33,
1.00"
Chevrolet/Pontiac Camaro & Firebird (93-02) Full Prep:
"3.42, 2.28, 1.45,1.00 or 2.95, 1.94,1.34, 1.00,0.73or 3.35, 1.93,1.29, 1.00,0. 61 or 2.88, 1.91, 1.33, 1.00 or 3.27, 1.98, 1.34, 1.00,
0.68 or 2.20,1.64,1.28,1.00 or 2.87,1.89,1.28,1.00,.81"
Chevrolet/Pontiac Camaro & Firebird (93-02) Restricted prep:
"2.97, 2.07, 1.43, 1.00, 0.80, 0.62 or 3.36, 2.07, 1.35, 1.00, .80, .62 or 2.66, 1.78, 1.30, 1.00, 0.74, 0.50 or 2.88, 1.91, 1.33, 1.00 or
2.20, 1.64,1.28,1.00"
Chevrolet Camaro SS (V8) (10-15) Restricted Prep:
"3.01, 2.07, 1.43, 1.0, .84, .57 or 2.88, 1.91, 1.33, 1.00 or 2.20, 1.64,1.28,1.00"
Chevrolet Camaro (10-15) Full Prep:
"3.42, 2.28, 1.45,1.00 or 2.95, 1.94,1.34, 1.00, 0.73or 3.35, 1.93,1.29, 1.00,0. 61 or 2.88, 1.91, 1.33, 1.00 or 3.27, 1.98, 1.34, 1.00,
0.68 or 2.20, 1.64,1.28,1.00 or 2.87,1.89,1.28,1.00,.81"
Chevrolet Camaro (16-) Full Prep:
"3.42, 2.28, 1.45,1.00 or 2.95, 1.94,1.34, 1.00, 0.73or 3.35, 1.93,1.29, 1.00,0. 61 or 2.88, 1.91, 1.33, 1.00 or 3.27, 1.98, 1.34, 1.00,
0.68 or 2.20, 1.64,1.28,1.00 or 2.87,1.89,1.28,1.00,.81"
Chevrolet Camaro, 1LE (16-):
"2.66,1.78,1.30, 0.74,.50 or 2.88, 1.91, 1.33, 1.00 or 2.20, 1.64,1.28,1.00 or 2.88, 1.91, 1.33, 1.00 or 2.20, 1.64,1.28,1.00"
Dodge Challenger (08-20) Restricted Preparation 5.7L, 6.1L, or 6.4L V8 (Iron block, Aluminum heads), 2 valves/cylinder:
"2.97, 2.1, 1.46, 1.00, 0.74, 0.50 or 2.26, 1.58, 1.19, 1.00, 0.77, 0.63 or 2.88, 1.91, 1.33, 1.00 or 2.20, 1.64,1.28,1.00"
Ford Mustang Incl. Cobra & Cobra R (79-93) and Mercury Capri (79-86) Full Prep:
"3.07, 1.72, 1.00, 0.70 or 2.95, 1.94, 1.34, 1.00, 0.63 or 3.35, 1.99, 1.33, 1.00, 0.68 or 2.87 1.89 1.28 1.00 0.81"
Ford Mustang Incl. Cobra & Cobra R (79-93) and Mercury Capri (79-86) with Restricted Prep Engine:
"2.95, 1.94, 1.34,1.00, 0.63 or 3.35,1.99,1.33, 1.00, 0.69 or 2.88, 1.91, 1.33, 1.00 or 3.27,1.98, 1.34, 1.00, 0.68, 3.66, 2.43, 1.69,
1.32, 1.00, .68. or 2.87,1.89,1.28,1.00,.81"
Ford Mustang Including Cobra 94-04 Full Prep:
"3.07, 1.72, 1.00, 0.70 or 2.95, 1.94, 1.34, 1.00, 0.63 or 3.35, 1.99, 1.33, 1.00, 0.68 or 2.88, 1.91, 1.33, 1.00 or 3.27, 1.98, 1.34,
1.00, 0.68 or 2.88, 1.91, 1.33, 1.00 or 3.27, 1.98, 1.34, 1.00, 0.68 or 2.20, 1.64,1.28,1.00 or 2.87 1.89 1.28 1.00 0.81"
Ford Mustang Cobra and GT 94-95 (Restricted Prep):
"3.35, 1.99, 1.33, 1.00, 0.68 or 2.88, 1.91, 1.33, 1.00 or 2.20, 1.64,1.28,1.00"
Ford Mustang including Cobra 96-04 (Restricted Prep) 4.6L two and four valve motor:
"3.35, 1.99, 1.33, 1.00, 0.68 or 3.27, 1.98, 1.34, 1.00, 0.67 or 3.37, 1.99, 1.33, 1.00, 0.68 or 3.38, 2.00, 1.32, 1.00, 0.68 or 2.88,
1.91, 1.33, 1.00 or 2.20, 1.64,1.28,1.00"
Ford Mustang GT (05-14) Full Prep:
"3.38, 2.00, 1.32, 1.00, 0.68 or 3.66, 2.43, 1.69,1.32, 1.00, 0.65 or 2.88, 1.91, 1.33, 1.00 or 2.20, 1.64,1.28,1.00"
Ford Mustang GT 5.0l (15-17) Restricted Preparation:
"3.66, 2.43, 1.69,1.32, 1.00, .65 or 4.69, 2.98,2.14, 1.76,1.52, 1.27,1.00, 0.85, 0.68, 0.63, or 3.24, 2.10, 1.42, 1.00, 0.81, .062. or
2.88, 1.91, 1.33, 1.00 or 2.20, 1.64,1.28,1.00"
Ford Mustang GT 5.0L (2018-) Restricted Preparation:
"2.97, 2.07, 1.43, 1.00, 0.84, 0.57 or 2.88, 1.91, 1.33, 1.00 or 2.20, 1.64,1.28,1.00"
Pontiac GTO (04-06) Restricted Prep.
"2.97, 2.07, 1.43, 1.00, 0.84, 0.57 or 2.88, 1.91, 1.33, 1.00 or 2.20, 1.64,1.28,1.00"

2025-01-01 AS ECU specs for LS engine

#37208 from Gary Mathews · Rule change · TB 25-01 (2025-01 Fastrack)

Summary

fasterAS LS-engine cars gain ECU freedom; Camaro/Firebird 93-02 LS1 removes fuel cell location restriction.

As printed in Fastrack

In AS SPEC LINES, Cadillac CTS-V (04-07) Restricted Prep., change Notes as follows:
"Fuel cells must be located within 24 inches of the standard tank. The 24 inch measurement is taken from the perimeter of the
stock and alternative fuel cell. Fuel filler location is unrestricted with installation of a safety fuel cell. Tremec TR6060
Transmission with 3.0 1, 2.07, 1.43, 1.0, .84, .57 ratios permitted. 11” wide wheels can be used until 3/1/25. Any ECM may be
used."
In AS SPEC LINES, Chevrolet Camaro, Pontiac Firebird (70-81) Restricted Prep ., add to Notes as follows:
"Any ECM may be used."
In AS SPEC LINES, Chevrolet/Pontiac Camaro & Firebird (82-92) 5.7L V-8 LS1, add to Notes as follows:

Show 14 more lines

"Any ECM may be used."
In AS SPEC LINES, Chevrolet/Pontiac Camaro & Firebird (93-02) Restricted Prep.5.7L V-8 LT1, add to Notes as follows:
"Any ECM may be used."
In AS SPEC LINES, Chevrolet/Pontiac Camaro & Firebird (93-02) Restricted Prep. 5.7L V-8 LT1; 98-02 , change Notes as follows:
"5.7L LS1:
GM Performance Parts camshaft Kit P/N-19355738 is permitted. Cylinder Bore, 99 mm; Stroke, 92 mm; Intake Valve Diameter,
50.8; Exhaust Valve Diameter, 39.4 mm; Throttle Body Bore, 75 mm; SLP Intake Lid (SLP part number 21044 (98-99) and 21045
(00-02)) is permitted.
~~Fuel cells must be located within 24 inches of the standard tank. The 24 inch measurement is taken from the perimeter of the~~
~~stock and alternative fuel cell. Fuel filler location is unrestricted with installation of a safety fuel cell.~~
1-3/4 headers allowed. For the LS1connecting rods Callies P/NCSC6100DS6A2AH, Scat rods P/N2-1CR6100-944, GM performance
rods P/N12649190. Any ECM may be used."
In AS SPEC LINES, Chevrolet Camaro SS (V8) (10-15) Restricted Prep., add to Notes as follows:
"Any ECM may be used."

2025-01-01 STU Merger GT3 to STU

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

Summary

wordingSTU-GT3 reclassified as STU-GT3U effective January 1, 2026.

As printed in 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)

Summary

slowerSTU GT3 TCR gains 275-width tire option with 100 lb weight penalty, but not in A compound.

As printed in 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."

Cal Club 2025 → Cal Club 2026 2025-02-22 to 2026-02-21

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

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

Summary

engineSTU BMW N54/N55 3.0L classified at Chart +3% minimum weight; N54 twin turbo not allowed.

As printed in 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)

Summary

fasterSTU Mini Cooper S SC supercharger pulley diameter reduced from 2.285 to 2.185.

As printed in 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)

Summary

fasterSTU Honda K20C1 Turbo I4 exempted from 3% DI weight adder in Spec Lines Table A.

As printed in 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 AS Race memo

#37902 from American Sedan Committee · Rule change · TB 25-03 (2025-03 Fastrack)

Summary

unclearAS Spec Lines removes ECM flexibility restriction from five Cadillac and Chevrolet/Pontiac V8 models.

As printed in Fastrack

In AS Spec Lines, change Notes as follows:
Cadillac CTS-V (04-07) Restricted Prep. 6.0L V8 (Aluminum block, Aluminum heads), LS2, 2 valves/cylinder:
"~~Any ECM maybe used.~~"
Chevrolet Camaro, Pontiac Firebird (70-81) Restricted Prep. 6.2L V8 (Aluminum Block, Aluminum Heads), 2 valves per cylinder:
"~~Any ECM maybe used.~~"
Chevrolet/Pontiac Camaro & Firebird (82-92)s 5.7L V-8 LS1 (Aluminum Block, Aluminum Heads) 2 valves per cylinder:
"~~Any ECM maybe used.~~"
Chevrolet/Pontiac Camaro & Firebird (93-02):

Show 3 more lines

"~~Any ECM maybe used.~~"
Chevrolet Camaro SS (V8) (10-15) Restricted Prep. 6.2L V8 (Aluminum Block, Aluminum Heads), 2 valves per cylinder:
"~~Any ECM maybe used.~~"

2025-03-01 STU Increase Minimum Weight

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

Summary

slowerSTU GT3U minimum weight increases 150 to 250 pounds.

As printed in Fastrack

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

2025-04-01 AS Flotek Head Plunge Cut Inconsistencies

#37502 from Pamela Richardson · Rule change · TB 25-04 (2025-04 Fastrack)

Summary

unclearAS Flotek Head plunge cut dimensions figure updated in GCR Section 9.1.6.

As printed in Fastrack

In GCR, Section 9.1.6., replace Figure 1 Value Seat Cutting Dimensions with the following:

2025-04-01 AS Notes clean up

#37693 from American Sedan Committee · Rule change · TB 25-04 (2025-04 Fastrack)

Summary

wordingAS class notes cleanup: multiple Camaro, Firebird, CTS-V, Challenger, Mustang specs and fuel cell/ECM/head restrictions removed.

As printed in Fastrack

In AS Spec Lines, change/add to Notes as follows:
Cadillac CTS-V (04-07):
"~~Fuel cells must be located within 24 inches of the standard tank. The 24 inch measurement is taken from the perimeter of the~~
~~stock and alternative fuel cell. Fuel filler location is unrestricted with installation of a safety fuel cell. Any ECM maybe used.~~ The
Drive Shaft Shop, Axle shaft part #'s 510220/510221 permitted."
Chevrolet Camaro, Pontiac Firebird (70-81) Full Prep:
"~~Engine built to A/S Build Sheet specifications with the following: Head Casting #s: 14101081, 14014416 Port Volume (Max.): 081~~
~~casting: 170.00 cc IN/65.00 EX; 416 Casting 168.00cc IN/60.00 EX with a 250 lb. weight reduction. Edelbrock Cylinder Head Part~~

Show 88 more lines

~~#s 608979, 608879.~~"
Chevrolet Camaro, Pontiac Firebird (70-81) Restricted Prep.:
"~~Any ECM maybe used.~~"
Chevrolet/Pontiac Camaro & Firebird (82-92) Full Prep.:
"~~Engine built to A/S Build Sheet specifications with the following: Head Casting #s: 14101081, 14014416 Port Volume (Max.): 081~~
~~cast¬ing: 170.00 cc IN/65.00 EX; 416 Casting 168.00cc IN/60.00 EX with a 250 lb weight reduction. Edelbrock Cylinder Head Part~~
~~#s 608979, 608879 are permitted. For regional competition only, unmodified GM Performance cylinder head part #s 19300955,~~
~~19300956 may be used with Allstar restrictor plate part# ALL26180 and 1.250 inserts part# ALL26186 installed between intake~~
~~manifold and insulator. Gaskets may be used (each gasket can be no thicker than .125 inches), one on each side of the restrictor.~~
~~All intake air must pass through the inserts of the restrictor plate. Alternate gear ratio sets 2.88, 1.91, 1.33, 1.00 or 3.27, 1.98,~~
~~1.34, 1.00, 0.68 are permitted. Flo Tek Head part #102-500 are permitted.~~"
Chevrolet/Pontiac Camaro & Firebird (82-92) Restricted prep engine:
"~~Any ECM maybe used.~~"
Chevrolet/Pontiac Camaro & Firebird (93-02) Full Prep:
"~~Engine built to A/S Build Sheet specifications with the following: Head Casting #’s: 14101081, 14014416; Port Volume (Max.):~~
~~081 casting: 170.00 cc IN/65.00 EX; 416 Casting 168.00cc IN/60.00 EX with a 250 lb weight reduction. Edelbrock Cylinder Head~~
~~Part #’s 608979, 608879 are permitted. For regional competition only, unmodified GM Performance cylinder head part #s~~
~~19300955, 19300956 may be used with Allstar restrictor plate part# ALL26180 and 1.250 inserts part# ALL26186 installed~~
~~between intake manifold and insulator. Gaskets may be used (each gasket can be no thicker than .125 inches), one on each side~~
~~of the restrictor. All intake air must pass through the inserts of the restrictor plate. Alternate gear ratio sets 2.88, 1.91, 1.33, 1.00~~
~~or 3.27, 1.98, 1.34, 1.00, 0.68 are permitted. Fuel cells must be located within 24 inches of the standard tank. The 24 inch~~
~~measurement is taken from the perimeter of the stock and alternative fuel cell. Fuel filler location is unrestricted with~~
~~installation of a safety fuel cell. Flo Tek Head part #102-500 are permitted.~~"
Chevrolet/Pontiac Camaro & Firebird (93-02) Restricted Prep:
"~~Fuel cells must be located within 24 inches of the standard tank. The 24 inch measurement is taken from the perimeter of the~~
~~stock and alternative fuel cell. Fuel filler location is unrestricted with installation of a safety fuel cell. Any ECM maybe used.~~"
Chevrolet Camaro SS (V8) (10-15) Restricted Prep:
"~~Fuel cells must be located within 24 inches of the standard tank. The 24 inch measurement is taken from the perimeter of the~~
~~stock and alternative fuel cell. Fuel filler location is unrestricted with installation of a safety fuel cell. Any ECM maybe used.~~"
Chevrolet Camaro (10-15) Full Prep:
"~~Engine built to A/S Build Sheet specifications with the following: Head Casting #’s: 14101081, 14014416; Port Volume (Max.):~~
~~081 casting: 170.00 cc IN/65.00 EX; 416 Casting 168.00cc IN/60.00 EX with a 200 lb weight reduction. Edelbrock Cylinder Head~~
~~Part #’s 608979, 608879 are permitted. Alternate gear ratio sets 2.88, 1.91, 1.33, 1.00 or 3.27, 1.98, 1.34, 1.00, 0.68 are~~
~~permitted. Fuel cells must be located within 24 inches of the standard tank. The 24-inch measurement is taken from the~~
~~perimeter of the stock and alternative fuel cell. Fuel filler location is unrestricted with installation of a safety fuel cell. Flo Tek~~
~~Head part #102-500 are permitted. Fuel cells must be located within 24 inches of the standard tank. The 24 inch measurement is~~
~~taken from the perimeter of the stock and alternative fuel cell. Fuel filler location is unrestricted with installation of a safety fuel~~
~~cell.~~"
Chevrolet Camaro (16-) Full Prep:
"~~Engine built to A/S Build Sheet specifications with the following: Head Casting #’s: 14101081, 14014416; Port Volume (Max.):~~
~~081 casting: 170.00 cc IN/65.00 EX; 416 Casting 168.00cc IN/60.00 EX with a 200 lb weight reduction. Edelbrock Cylinder Head~~
~~Part #’s 608979, 608879 are permitted, Flo Tek Head part #102-500 are permitted.~~"
Chevrolet Camaro, 1LE (16-):
"~~60mm flat plate restrictor required. Any ECM maybe used.~~"
Dodge Challenger (08-20) Restricted Preparation:
"~~80mm flat plate restrictor is required on the 6.4L engine. Fuel cells must be located within 24 inches of the standard tank. The~~
~~24 inch measurement is taken from the perimeter of the stock and alternative fuel cell. Fuel filler location is unrestricted with~~
~~installation of a safety fuel cell.~~"
Ford Mustang Incl. Cobra & Cobra R (79-93) and Mercury Capri (79-86) Full Prep:
"~~Engine built to A/S Build Sheet specifications with the following: Head Casting #s: F3ZE AA (GT40), F1ZE-AA (GT-40), F77E-AA~~
~~(GT- 40P), Port Volume (Max.): 143.00cc IN/54.00cc EX (GT-40 & GT-40P) with a 250 lb weight reduction. Edelbrock Cylinder~~
~~Head Part #s 602579, 602479 are permitted. For regional competition only, unmodified Ford Performance cylinder head part #s~~
~~M-6049-Z304DA7, M-6049-Z304D may be used with Allstar restrictor plate part# ALL26180 and 1.250 inserts part# ALL26186~~
~~installed between intake manifold and insulator. Gaskets may be used (each gasket can be no thicker than .125 inches), one on~~
~~each side of the restrictor. All intake air must pass through the inserts of the restrictor plate. Alternate gear ratio sets 2.88, 1.91,~~
~~1.33, 1.00 or 3.27, 1.98, 1.34, 1.00, 0.68 are permitted. Flo Tek Part # 203-500 are permitted.~~"
Ford Mustang Incl. Cobra & Cobra R (79-93) and Mercury Capri(79-86) with Restricted Prep Engine:
"~~62mm flat plate restrictor is required. Fuel cells must be located within 24 inches of the standard tank. The 24 inch~~
~~measurement is taken from the perimeter of the stock and alternative fuel cell. Fuel filler location is unrestricted with~~
~~installation of a safety fuel cell.~~ MMR Secondary Timing Chain Tensioner Bracket #467893 is permitted."
Ford Mustang Including Cobra 94-04 Full Prep:
"~~Engine built to A/S Build Sheet specifications with the following: Head Casting #s: F3ZE AA (GT40), F1ZE-AA (GT-40), F77E-AA~~
~~(GT- 40P), Port Volume (Max.): 143.00cc IN/54.00cc EX (GT-40 & GT-40P) with a 250 lb weight reduction. Edelbrock Cylinder~~
~~Head Part #s 602579, 602479 are permitted. For regional competition only, unmodified Ford Performance cylinder head part #s~~
~~M-6049-Z304DA7, M-6049-Z304D may be used with Allstar restrictor plate part# ALL26180 and 1.250 inserts part# ALL26186~~
~~installed between intake manifold and insulator. Gaskets may be used (each gasket can be no thicker than .125 inches), one on~~
~~each side of the restrictor. All intake air must pass through the inserts of the restrictor plate. Alternate gear ratio sets 2.88, 1.91,~~
~~1.33, 1.00 or 3.27, 1.98, 1.34, 1.00, 0.68 are permitted. Flo Tek Part # 203-500 are permitted.~~"
Ford Mustang GT (94-04) with Restricted Prep Engine:
"MMR Secondary Timing Chain Tensioner Bracket #467893 is permitted."
Ford Mustang Cobra and GT 94-95(Restricted Prep):
"~~1st Generation 5.0l Coyote 11-14 62mm FPR 2nd Generation 5.0l Coyote 15-17 61mm FPR Alternate transmission Ratios 3.66,~~
~~2.43, 1.69, 1.32, 1.00, .68.~~ MMR Secondary Timing Chain Tensioner Bracket #467893 is permitted."
Ford Mustang including Cobra 96-04 (Restricted Prep):
"~~1st Generation 5.0l Coyote 11-14 62mm FPR 2nd Generation 5.0l Coyote 15-17 61mm FPR Alternate transmission Ratios 3.66,~~
~~2.43, 1.69, 1.32, 1.00, .68.~~ MMR Secondary Timing Chain Tensioner Bracket #467893 is permitted."
Ford Mustang Coupe GT (05-14) Restricted Prep.:
"~~1st Generation 5.0l Coyote 11-14 62mm FPR 2nd Generation 5.0l Coyote 15-17 61mm FPR Alternate transmission Ratios 3.66,~~
~~2.43, 1.69, 1.32, 1.00, .68.~~ MMR Secondary Timing Chain Tensioner Bracket #467893 is permitted. MT82 6 speed is permitted."
Ford Mustang GT (05-14) with Restricted Prep Engine:
"~~1st Generation 5.0l Coyote 11-14 62mm FPR 2nd Generation 5.0l Coyote 15-17 61mm FPR Alternate transmission Ratios 3.66,~~
~~2.43, 1.69, 1.32, 1.00, .68.~~ MMR Secondary Timing Chain Tensioner Bracket #467893 is permitted. MT82 6 speed is permitted."
Ford Mustang GT 5.0l (15-17) Restricted Preparation:
"~~61mm flat plate restrictor required. Fuel cells must be located within 24 inches of the standard tank. The 24 inch measurement~~
~~is taken from the perimeter of the stock and alternative fuel cell. Fuel filler location is unrestricted with installation of a safety~~
~~fuel cell.~~ MMR Secondary Timing Chain Tensioner Bracket #467893 is permitted."
Ford Mustang GT 5.0L (2018-):
"~~60mm flat plate restrictor required.~~ MMR Secondary Timing Chain Tensioner Bracket #467893 is permitted."

2025-05-01 STL E&O: SMX Allowance in STL

#37945 from Greg Amy · Rule change · TB 25-05 (2025-05 Fastrack)

Summary

unclearSTL Mazda MX5 Challenge minimum weight now references GCR 9.1.7.1 instead of 2500 lbs; spec components removed, only alternative tires allowed.

As printed in Fastrack

In STL Spec Lines, Table B, Mazda Spec MX5 Challenge, change as follows:
Minimum Weight: "~~2500~~ See 9.1.7.1."
Notes: "~~Mazda MX5 Challenge car must utilize the following components: Roush CNC cylinder head 0000-01-5300,Mahle~~
~~standard or +0.005 0000-01-5310, OEM camshaft, 11:1 compression ratio, header 0000-06-5407-NC, exhaust 0000-06-5427-NC,~~
~~cold air intake 0000- 06-5150-KT, ECU flash 0000-01-5379, Pagid front brake pads 0000-03-5104-SP or endurance pads 0000-03-~~
~~5104-EN, Pagid rear brake pads 0000-03-5114-SP or endurance pads 0000-03-5114-EN, Penske front shock 0000-04-5291-SA,~~
~~Penske rear shock 0000-04-5292-SA, Penske rear mount kit 0000-04-5358, Front mount kit 0000-04-5359, Front offset bushing~~
~~0000-04-5407-NC, Eibach front springs 0000-04-9700-08, Eibach rear springs 0000-04-9400-07, Eibach helper springs 0000-04-~~

Show 5 more lines

~~9926, Eibach front sway bar 0000-04-5306-FT, Eibach rear sway bar 0000-04-5306-RR, Interior finish panels 0000-07-5822, C&R~~
~~radiator/oil cooler assembly 0000-01-5504-CR, Oil cooler adapter and lines 0000-01-5511-KT, ACT clutch 0000-02-5004-G6,~~
~~wheels 17x8 #0000-04-5706-GM, # 0000- 04-5706-SL, and Toyo RR 235-40-17 dry, Toyo RA1 235-40-17 wet. Alternative tires on~~
~~17x7 wheels per STL rules. No other Super Touring modifications or allowances permitted except as noted in this spec line.~~ Must
conform completely to GCR 9.1.7.1, except alternative tires (only) per STL regs allowed."

Applies to Mazda Miata on this page: Jared Korth, Ricardo Arruda, Gavin Wardle, Ryan Gutile, Bryce Johnson, Andy Chittum, Adrian Comstock

2025-05-01 STU Wheel Size Inconsistency

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

Summary

wordingSTU wheel width rules clarified: cars ≤2,850 lbs max 8 inches, cars >2,850 lbs max 9 inches.

As printed in 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 AS Errors and Omission

#38055 from American Sedan Committee · Rule change · TB 25-05 (2025-05 Fastrack)

Summary

slowerAS Ford Mustang GT 5.0L (15-17) flat plate restrictor reduced from 67mm to 64mm.

As printed in Fastrack

In AS Spec Lines, Ford Mustang GT 5.0l (15-17), Flat Plate Restrictor Size, change as follows:
"~~67mm~~ 64mm"

2025-05-01 AS Request to Add LS1/LS6 Intakes for 5.3L Truck Engine EnO

#38197 from Jim Clark · Rule change · TB 25-05 (2025-05 Fastrack)

Summary

wordingAS LS1/LS6 5.3L truck engine gains four approved intake part numbers: 12561269, 88894095, 89017363, 89017364.

As printed in Fastrack

In GCR, Section 9.1.6.F., add the following to Intake Part #’s:
"17113697, 19418185, 89017230, 89017363, 89017364, ~~and~~ 89017365, 12561269 and 88894095"

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

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

Summary

fasterSTU Spec Line GT3U minimum weight reduced from plus 250 to plus 225 pounds; wheel and tire options clarified with weight adjustments.

As printed in 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

Show 1 more lines

including the 225 lbs."

2025-06-01 AS Errors and Omissions

#38234 from American Sedan Committee · Rule change · TB 25-06 (2025-06 Fastrack)

Summary

wordingAS Ford Mustang GT 05-14 Restricted Prep Engine gains alternative gear ratios: 3.66, 2.43, 1.69, 1.32, 1.00, .65

As printed in Fastrack

In AS Spec Lines, Ford Mustang GT (05-14) with Restricted Prep Engine, add to Gear Ratios the following:
"or 3.66, 2.43, 1.69, 1.32, 1.00, .65"

Applies to Ford Mustang on this page: Roger Eagleton, Ross Murray, Matt Lituchy, Michael Lowe, Pratt Cole

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

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

Summary

unclearSTU 2.8-3.2L N/A engines now allow 245 max tire width; over 3150 lbs may run 275 with 2% weight penalty.

As printed in 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 AS RE: Previous Letter 37695 Update

#38245 from Michael Kamalian · Rule change · TB 25-07 (2025-07 Fastrack)

Summary

fasterAS Ford Mustang GT 5.0 2018- weight reduced from 3600 to 3525 lbs.

As printed in Fastrack

In AS Spec Lines, Ford Mustang GT 5.0 (2018-), change Weight as follows:
"~~3600~~ 3525"

Applies to Ford Mustang on this page: Roger Eagleton, Ross Murray, Matt Lituchy, Michael Lowe

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

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

Summary

wordingSTU Mazda MZR may use Goodwin 61-2510 or Gato Performance 31972 intake manifold.

As printed in 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 STU Requesting Approval of the JDM Honda h23a

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

Summary

cars addedSTU Honda JDM H23a added, 2259cc displacement, minimum weight per Chart, must meet ST engine regulations.

As printed in 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)

Summary

slowerSTU-TCR tire width increases to 275 with weight adder raised from 100 to 150 pounds.

As printed in 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)

Summary

fasterSTL/STU Lotus weight reduced: Evora GT4 to 2700 lbs, Elise Cup R to 2250 lbs, Elise/Exige SC to 2450-2550 lbs.

As printed in 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"

2025-08-01 STL Lotus Weight Reduction

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

Summary

fasterSTL/STU Lotus weight reduced: Evora GT4 to 2700 lbs, Elise Cup R to 2250 lbs, Elise/Exige SC to 2450-2550 lbs.

As printed in Fastrack

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

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

Summary

fasterSTU Lotus Elise SC and Exige SC weight reduced from 2450 to 2250 lbs.

As printed in Fastrack

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

2025-11-01 AS Cadillac CTS-V BOP Weight Change

#38640 from Alex Lozano · Rule change · TB 25-09 (2025-09 Fastrack)

Summary

fasterAS Cadillac CTS-V 04-07 Restricted Prep weight reduced 50 lbs to 3400.

As printed in Fastrack

In AS Spec Lines, Cadillac CTS-V (04-07) Restricted Prep., change Weight as follows:
"(Effective 11/1/2025) ~~3450~~ 3400"

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)

Summary

slowerSTU Honda K24 engine swap weight increases by 2% effective November 1, 2025.

As printed in Fastrack

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

2025-12-01 STU Turbo Inlet Restrictor Table

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

Summary

slowerSTU 36mm restrictor allows 2830 lbs (up 10 lbs from 2820); 37mm allows 2980 lbs (down 5 lbs from 2985).

As printed in 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)

Summary

slowerSTU cars over 3150 lbs lose 275-tire option with 2% weight adder.

As printed in 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 AS 1994 Mustang Spec Line Request

#39104 from Barry Borgschatz, Jr · Rule change · TB 25-12 (2025-12 Fastrack)

Summary

unclearAS Ford Mustang GT 94-04 Restricted Prep Engine now permits Ford Motorsport M-6250-F303 camshaft.

As printed in Fastrack

In AS Spec Lines, Ford Mustang GT(94-04) with Restricted Prep Engine, add to notes the following:
"Ford Motorsport #M-6250-F303 camshaft is permitted."

Applies to Ford Mustang on this page: Roger Eagleton, Ross Murray, Matt Lituchy, Michael Lowe, Pratt Cole

2025-12-01 STU STU Honda Engine weight penalty

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

Summary

fasterSTU Honda K20 and K24 engines lose 2% minimum weight penalty.

As printed in 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 AS Restrictor Plate Change for Gen 2 Ford Coyote Engine

#39501 from American Sedan Committee · Rule change · TB 26-01 (2026-01 Fastrack)

Summary

slowerAS Ford Mustang Restricted Prep engines lose 3 mm restrictor plate, from 64 mm to 61 mm.

As printed in Fastrack

In AS Spec Lines, change Restrictor as follows:
Ford Mustang Incl. Cobra and Cobra R (79-93) and Mercury Capri (79-86) with Restricted Prep Engine: "~~64 mm~~ 61 mm"
Ford Mustang GT (94-04) with Restricted Prep Engine: "~~64 mm~~ 61 mm"
Ford Mustang Coupe GT (05-14) Restricted Prep 5.0L/6 speed 4 valves per cylinder: "~~64 mm~~ 61 mm"
Ford Mustang GT (05-14) with Restricted Prep Engine: "~~64 mm~~ 61 mm"
Ford Mustang GT 5.0L (15-17) Restricted Preparation: "~~64 mm~~ 61 mm"

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)

Summary

fasterSTU Mazda MZR (LF, L3, L5) Turbo classified; Jack Spania Racing 70 mm intake manifold and Fab9 Tuning bottom-mount turbo kit approved.

As printed in 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

Show 7 more lines

Varies Chart Short blocks, heads, and intakes may be freely
swapped within these engine designations. May
use Jack Spania Racing 70 mm sheet-metal
aluminum Intake manifold. Must use stock
throttle body or Acura part number 16400-PND-
A17. Fab9 Tuning bottom-mount turbo kit
approved with one of the STU approved Turbos.

2026-01-01 STL Weight adjustment for STL

#39579 from Super Touring Committee · Rule change · TB 26-01 (2026-01 Fastrack)

Summary

slowerSTL minimum weights increase across all classes, 1300 cc gains 195 lbs to 1950, up to 1850 cc at 2500.

As printed in Fastrack

In GCR, Section 9.1.4.2.H.1. change Minimum Weight on chart as follows:

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

2026-02-01 AS Edelbrock manifold (& timing kit) to Chevy LS Spec Lines Request

#39055 from Jason Smith · Rule change · TB 26-01 (2026-01 Fastrack)

Summary

cars addedAS Chevy LS adds Edelbrock Performer RPM 71187 intake manifold with MSD 6014 ignition and 4776 Holly carburetor as spec line option.

As printed in Fastrack

In GCR, Section 9.1.6.D.2.h.2., add the following:
"(Effective 2/1/2026) i. Weight based on full preparation chassis choice spec line for GM LM7 5.3L
Carburetor Option:
Must use the full prep 4776 holly carburetor and spacer gasket
Edelbrock Performer RPM 71187 intake manifold
MSD 6014 ignition box
(Edelbrock part # kit 7118)"

What the rules allowed changed as listed; this does not say what any particular car ran.