BoP Lab / Buttonwillow Raceway Park

FP + GT3U + EP 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.

Pos	Car	Driver	Class	#	Lap	Theoretical	Qual	Race	5-lap stint	Consistency	Trap	S1	S2	S3
1	Mazda Miata	Joe Carr	EP	12	1:52.034 B-P	1:52.034	1:59.603 A-Q1	1:59.157 A-R1	1:59.373 A-R1	+0.724 A-R1	131.6 A-R1	31.719 B-P	32.405 B-P	49.966 B-P
2	Mazda MX-5	Glen McCready	EP	4	1:53.088 B-Q2	1:52.984	1:53.088 B-Q2	1:53.487 B-R2	1:54.617 B-R2	+2.232 B-R2	125.6 B-P	30.761 B-R2	32.765 B-Q1	49.458 B-Q2
3	Mazda RX-7	Michael Lewis 2+ cars	FP	32	1:55.440 B-R2	1:55.401	1:56.121 B-Q1	1:55.440 B-R2	1:56.358 B-R2	+2.235 B-R2	128.8 A-R2	31.255 B-R2	33.299 B-Q2	50.847 B-R2
4	Mazda RX-7	Michael Lewis 2+ cars	GT3U	32	1:55.650 B-R2	1:55.440	2:00.536 B-Q1	1:55.650 B-R2	1:56.657 B-R2	+2.951 B-R2	129.8 B-P	31.468 B-R2	33.670 B-R2	50.302 B-R2
5	Nissan Sentra SE-R	Brian Linn	FP	123, 3	1:55.722 B-R2	1:55.294	1:57.239 B-Q1	1:55.722 B-R2	1:56.460 B-R2	+1.971 B-R2	128.3 B-P	31.416 B-R2	33.400 B-R2	50.478 B-R2
6	Volkswagen GTI	Tim Linerud	FP	95	1:56.016 B-P	1:56.016		2:06.156 B-R1	2:07.807 B-R1	+3.270 B-R1	93.4 B-R2	33.738 B-R1	35.656 B-P	55.246 B-P
7	Mazda MIata	Steven Powers	FP	145	1:56.276 B-R2	1:55.982	1:57.032 B-Q1	1:56.276 B-R2	1:56.620 B-R2	+0.759 B-R2	134.3 A-Q2, A-R2	31.570 B-R2	33.696 B-R2	50.716 B-R2
8	Mazda RX-7	Kurt Frietzsche	EP	40	1:56.468 B-Q1	1:55.599	1:56.468 B-Q1	1:56.573 B-R1	1:57.721 B-R1	+1.914 B-R1	120.7 A-R2	31.324 B-Q1	34.071 B-R1	50.204 B-R1
9	Mazda RX-7	Brandon Droese	EP	02	1:56.943 B-Q1	1:56.657	1:56.943 B-Q1	1:58.611 B-R1	1:58.767 B-R1	+0.718 B-R1	94.1 B-Q1, B-R1	31.953 B-R1	33.891 B-Q1	50.813 B-Q1
10	Fiat X/1 9	Daniel Snow	FP	1	1:59.128 B-R2	1:58.152	2:00.398 B-Q1	1:59.128 B-R2	1:59.511 B-R2	+0.364 B-R2	137.8 A-R2	31.878 B-R2	34.053 B-R2	52.221 A-R2
11	BMW E30	Sean Lovett	EP	37	2:00.712 A-Q2	2:00.625	2:00.712 A-Q2	2:01.864 A-R2	2:02.200 A-R1	+0.528 A-R1	127.6 A-Q2	32.761 A-Q1	34.806 A-Q1	53.058 A-Q2
12	Porsche Boxster	William Robinson	EP	198	2:01.940 A-Q1	2:01.634	2:01.940 A-Q1	2:02.887 A-R1	2:03.347 A-R1	+1.312 A-R1	130.6 A-Q2	32.969 A-Q1	35.257 A-Q1	53.408 A-Q1
13	Mazda RX-7	Justin Graham	GT3U	50	2:03.073 B-R2	2:03.073	2:07.538 B-Q1	2:03.073 B-R2	2:07.183 B-R1	+2.448 B-R1	101.0 B-R1	33.001 B-R2	35.220 B-R2	54.852 B-R2
14	Mazda MX-5	Whitfield Gregg	EP	17	2:03.660 B-Q2	2:03.314	2:03.660 B-Q2	2:04.085 B-R1	2:05.470 B-R2	+2.529 B-R2	97.7 B-R2	33.862 B-R2	35.422 B-R1	54.030 B-Q2
15	Porsche 914-4	Garey Raymond >115%	FP	29	2:15.932 B-R2	2:15.932	2:21.274 B-Q1	2:15.932 B-R2	2:17.314 B-R2	+3.922 B-R2	84.8 B-R1	37.237 B-R2	39.091 B-R2	59.604 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 MIata	EP/FP	2	1:52.034Joe Carr	1:57.032Steven Powers	1:56.276Steven Powers	134.3Steven Powers	31.570Steven Powers	32.405Joe Carr	49.966Joe Carr
Mazda Miata	EP	1	1:52.034Joe Carr	1:59.603Joe Carr	1:59.157Joe Carr	131.6Joe Carr	31.719Joe Carr	32.405Joe Carr	49.966Joe Carr
Mazda MIata	FP	1	1:56.276Steven Powers	1:57.032Steven Powers	1:56.276Steven Powers	134.3Steven Powers	31.570Steven Powers	33.696Steven Powers	50.716Steven Powers
Mazda MX-5	EP	2	1:53.088Glen McCready	1:53.088Glen McCready	1:53.487Glen McCready	125.6Glen McCready	30.761Glen McCready	32.765Glen McCready	49.458Glen McCready
Mazda RX-7	EP/FP/GT3U	4	1:55.440Michael Lewis	1:56.121Michael Lewis	1:55.440Michael Lewis	129.8Michael Lewis	31.255Michael Lewis	33.299Michael Lewis	50.204Kurt Frietzsche
Nissan Sentra SE-R	FP	1	1:55.722Brian Linn	1:57.239Brian Linn	1:55.722Brian Linn	128.3Brian Linn	31.416Brian Linn	33.400Brian Linn	50.478Brian Linn
Volkswagen GTI	FP	1	1:56.016Tim Linerud		2:06.156Tim Linerud	93.4Tim Linerud	33.738Tim Linerud	35.656Tim Linerud	55.246Tim Linerud
Fiat X 1/9	FP	1	1:59.128Daniel Snow	2:00.398Daniel Snow	1:59.128Daniel Snow	137.8Daniel Snow	31.878Daniel Snow	34.053Daniel Snow	52.221Daniel Snow
BMW E30	EP	1	2:00.712Sean Lovett	2:00.712Sean Lovett	2:01.864Sean Lovett	127.6Sean Lovett	32.761Sean Lovett	34.806Sean Lovett	53.058Sean Lovett
Porsche Boxster	EP	1	2:01.940William Robinson	2:01.940William Robinson	2:02.887William Robinson	130.6William Robinson	32.969William Robinson	35.257William Robinson	53.408William Robinson
Porsche 914-4	FP	1	2:15.932Garey Raymond	2:21.274Garey Raymond	2:15.932Garey Raymond	84.8Garey Raymond	37.237Garey Raymond	39.091Garey Raymond	59.604Garey Raymond

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

2023-04-01 EP Investigate Parity of Z3

#33343 from Tim Schreyer · Rule change · TB 23-01 (2023-01 Fastrack)

Summary

slowerEP BMW Z3 2.5L intake restrictor reduced from 58mm to 56mm flat plate.

As printed in Fastrack

Effective 4/1/2023 In EP Spec Line BMW Z3 2.5L, change Notes as follows:
"58 56mm Flat Plate Intake Restrictor is required with both stock or alternate throttle body."

2023-05-01 FP Classification Request for 1978 Toyota Celica

#34097 from Bob Pharr · Rule change · TB 23-05 (2023-05 Fastrack)

Summary

cars added1978-80 Toyota Celica classified FP Prep Level 2, 2100-2205 lbs, 2190cc SOHC, 11.0:1 compression, .450" valve lift max.

As printed in Fastrack

In FP Spec Lines, classify Toyota Celica (78-80) as follows:

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

2023-06-01 EP 914-6 Valve Size Correction

#34185 from Kip VanSteenburg · Rule change · TB 23-06 (2023-05 Fastrack)

Summary

fasterEP Porsche 914-6 2.0L intake valves increase to 2.0 mm, exhaust valves corrected to 38.0 mm.

As printed in Fastrack

In EP Spec Lines, Porsche 914 - 6 2.0L, change Valves IN & EX mm/(in.) as follows:
"(I) 4~~1.9~~ 2.0/(1.65)
(E) 38.1 0/(1.50)"

2023-06-01 FP Request to Classify Sonic and Fiesta in HP

#34264 from Greg Amy · Rule change · TB 23-06 (2023-05 Fastrack)

Summary

wordingFord Fiesta HP and Chevrolet Sonic FP model year ranges extended from 2016 to 2019.

As printed in Fastrack

In HP, adjust model years of the "Ford Fiesta (11-16)" spec line as follows:
"Ford Fiesta (11-16 9)"
In FP, adjust model years of the "Chevrolet Sonic (12-16)" spec line as follows:
"Chevrolet Sonic (12-16 9)"

2023-07-01 FP ITC to FP?

#34286 from David Snow · Rule change · TB 23-06 (2023-07 Fastrack)

Summary

cars addedHP Volkswagen Rabbit Cabriolet 1780 removed; Rabbit 1588 and 1715 reclassified with engine sizes and year ranges specified.

As printed in Fastrack

In HP Spec Lines, Volkswagen Rabbit Cabriolet 1780, delete in its entirely:
In HP, Spec Lines, Volkswagen Rabbit, change Title as follows:
“Volkswagen Rabbit 1588 ~~(includes Cabriolet / convertible)~~”
“Volkswagen Rabbit 1715 ~~(81-84) (excl. conv.)~~”
“Volkswagen Rabbit ~~GTI~~ 1780 ~~(83-84)~~”

2023-07-01 FP Correct Intake Valve Size on 1500cc Midget/Spitfire

#34419 from Production Committee · Rule change · TB 23-06 (2023-05 Fastrack)

Summary

wordingFP and HP Sprite, Midget, and Spitfire 1500 intake valve size corrected to 36.6/(1.44).

As printed in Fastrack

In FP Spec Lines, Austin-Healey Sprite Mk. I, II,III, IV MG Midget Mk I,II, III, IV & 1500, change Intake Valve Size as follows:
"(I) 36.6~~5.3~~/(1.44)"
In FP Spec Lines, Triumph Spitfire Mk. IV & 1500, change Intake Valve Size as follows:
"(I) 36.6~~5.5~~/(1.440)"
In HP Spec Lines, Triumph Spitfire 1500, change Intake Valve Size as follows:
"(I) 36.6~~5.5~~/(1.440)"
In HP Spec Lines, Triumph Spitfire Mk. III & IV 1500, change Intake Valve Size as follows:
"(I) 36.6~~5.5~~/(1.440)"

2023-07-01 EP Correct Intake Valve Size on 1500cc Midget/Spitfire

#34419 from Production Committee · Rule change · TB 23-06 (2023-05 Fastrack)

Summary

wordingFP and HP Sprite, Midget, and Spitfire 1500 intake valve size corrected to 36.6/(1.44).

As printed in Fastrack

2023-09-01 EP Hub Note Clean Up In EP TR8 Spec Line

#34649 from Jeff young · Rule change · TB 23-09 (2023-09 Fastrack)

Summary

wordingEP Triumph TR8 78-81 removes alternate front hub allowance note; stock hubs now required.

As printed in Fastrack

In the EP Spec Lines, Triumph TR8 (78-81), remove the following wording from Notes:
"~~Alternate front hubs are allowed provided they are of the same external dimensions as stock and weigh no less than the stock~~
~~hubs.~~"

2023-09-01 EP Triumph GT6 Adjustments

#34662 from ANTHONY PARKER · Rule change · TB 23-09 (2023-09 Fastrack)

Summary

unclearEP Triumph GT6 carburetors change from SU or Stromberg to 1.5" Auto-type.

As printed in Fastrack

In EP Spec Lines, Triumph GT6, change Carburetor. No. & Type as follows:
"(2) 1.5” ~~SU or Stromberg~~ Auto-type carburetor(s)"

2023-09-01 EP Triumph GT6 Adjustments: Brakes

#34663 from ANTHONY PARKER · Rule change · TB 23-09 (2023-09 Fastrack)

Summary

wordingEP Triumph GT6 brakes may now use TR-6 standard or alternate calipers and discs.

As printed in Fastrack

In EP Spec Lines, Triumph GT6, add the following to Brakes Alt.: mm/(in.):
"(F) Calipers & discs from TR-6 (std. or alt)"

2023-12-01 FP Porsche 944/924S Rule Change Request

#35002 from Adam Achepohl · Rule change · TB 23-12 (2023-12 Fastrack)

Summary

cars addedEP Porsche 944/924S combines 2.5L and 2.7L variants with new weights: 2250–2415 lbs depending on engine and year.

As printed in Fastrack

In EP Spec Lines, delete the Porsche 944/924S 2.5L (2V) (83-88) spec line entirely, and create a new spec line for Porsche
944/924S 2.5L(2V) 2.7L(2V) (83-89) as follows:

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

2023-12-01 EP Porsche 944/924S Rule Change Request

#35002 from Adam Achepohl · Rule change · TB 23-12 (2023-12 Fastrack)

Summary

cars addedEP Porsche 944/924S combines 2.5L and 2.7L variants with new weights: 2250–2415 lbs depending on engine and year.

As printed in Fastrack

In EP Spec Lines, delete the Porsche 944/924S 2.5L (2V) (83-88) spec line entirely, and create a new spec line for Porsche
944/924S 2.5L(2V) 2.7L(2V) (83-89) as follows:

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

2023-12-01 FP FP and HP Toyota Corolla

#35030 from Keith Church · Rule change · TB 23-12 (2023-12 Fastrack)

Summary

fasterFP Toyota Corolla 2TC loses 43 lbs to 1810; HP Corolla loses 50–52 lbs to 1910–2006.

As printed in Fastrack

In FP Spec Lines, Toyota Corolla 2TC (71-74), change weight as follows:
"~~1853~~ 1810"
In HP Spec Lines, Toyota Corolla (71-74), change weight as follows:
“~~1960~~ 1910
* ~~2009~~ 1958
** ~~2058~~ 2006”

2023-12-01 FP Triumph GT6 Adjustments

#35054 from ANTHONY PARKER · Rule change · TB 23-12 (2023-12 Fastrack)

Summary

fasterEP Triumph GT6 minimum weight reduced to 1800 lbs.

As printed in Fastrack

In EP Spec Lines, Triumph GT6, change weight as follows:
"~~1830~~ 1800"

2023-12-01 EP Triumph GT6 Adjustments

#35054 from ANTHONY PARKER · Rule change · TB 23-12 (2023-12 Fastrack)

Summary

fasterEP Triumph GT6 minimum weight reduced to 1800 lbs.

As printed in Fastrack

In EP Spec Lines, Triumph GT6, change weight as follows:
"~~1830~~ 1800"

2024-01-01 FP FP data

#35060 from Production Committee · Rule change · TB 24-01 (2024-01 Fastrack)

Summary

slowerFP Acura Integra LS and Honda Del Sol VTEC minimum weights increase 25–78 lbs across all configurations.

As printed in Fastrack

In FP Spec Line, Acura Integra LS (94-01), change weight as follows:
"~~2235~~ 2260
*~~2291~~ 2317
**~~2347~~ 2373"
In FP Spec Line, Honda Del Sol VTEC (94-97), change weight as follows:
"~~2190~~ 2265
*~~2245~~ 2322
**~~2300~~ 2378"

2024-01-01 FP Request to Review Z3 2.5 Spec Line

#35073 from Tim Schreyer · Rule change · TB 24-01 (2024-01 Fastrack)

Summary

slowerEP BMW Z3 2.5L weight increases to 2500 lbs, 2563 lbs with turbo, 2625 lbs with supercharger.

As printed in Fastrack

In EP spec line, BMW Z3 2.5L, change weight as follows:
"~~2450~~ 2500
*~~2511~~ 2563
**~~2573~~ 2625"

2024-01-01 EP Request to Review Z3 2.5 Spec Line

#35073 from Tim Schreyer · Rule change · TB 24-01 (2024-01 Fastrack)

Summary

slowerEP BMW Z3 2.5L weight increases to 2500 lbs, 2563 lbs with turbo, 2625 lbs with supercharger.

As printed in Fastrack

In EP spec line, BMW Z3 2.5L, change weight as follows:
"~~2450~~ 2500
*~~2511~~ 2563
**~~2573~~ 2625"

2024-01-01 FP Corrections to Honda Spec Lines in FP

#35250 from Jonathan Spiegel · Rule change · TB 24-01 (2024-01 Fastrack)

Summary

unclearFP Honda throttle body specs corrected: Civic 1.5 to 42", Si to 55", CRX variants adjusted.

As printed in Fastrack

In FP Spec Lines, change Fuel Injected Equipped Throttle Body Inside Diameter as follows:
Acura Integra GSR (92-93): "58"
Honda Civic 1.5 (88-91): "NA 42"
Honda Civic EX (90-91): "55"
Honda Civic Si (88-91): “42 55”
Honda CRX 1.5 (88-91): “~~33 (primary) 42 (secondary)~~ 42”
Honda CRX / CRX Si (84-87): ”42 33 (primary) 42 (secondary)”
Honda CRX Si (88-91): ”NA 55”

2024-01-01 FP Miata Alternate Head

#35253 from Don Tucker · Rule change · TB 24-01 (2024-01 Fastrack)

Summary

fasterEP Mazda MX-5 1.8L 1990-97 minimum weight drops to 2150 lbs; 1994-97 variants to 2000, 2050, 2100 lbs respectively.

As printed in Fastrack

In EP Spec Lines, Mazda MX-5 /Miata 1.8L (90-97), change weight as follows:
"~~2200~~ 2150"
Mazda MX-5 /Miata (94-97)
"~~2035~~ 2000
*~~2086~~ 2050
**~~2137~~ 2100"

Applies to Mazda MIata on this page: Joe Carr

Applies to Mazda MX-5 on this page: Glen McCready, Whitfield Gregg

2024-01-01 EP Miata Alternate Head

#35253 from Don Tucker · Rule change · TB 24-01 (2024-01 Fastrack)

Summary

fasterEP Mazda MX-5 1.8L 1990-97 minimum weight drops to 2150 lbs; 1994-97 variants to 2000, 2050, 2100 lbs respectively.

As printed in Fastrack

In EP Spec Lines, Mazda MX-5 /Miata 1.8L (90-97), change weight as follows:
"~~2200~~ 2150"
Mazda MX-5 /Miata (94-97)
"~~2035~~ 2000
*~~2086~~ 2050
**~~2137~~ 2100"

Applies to Mazda MIata on this page: Joe Carr

Applies to Mazda MX-5 on this page: Glen McCready, Whitfield Gregg

2024-01-01 FP Triumph GT6 Adjustments

#35255 from Anthony Parker · Rule change · TB 24-01 (2024-01 Fastrack)

Summary

fasterEP Triumph GT6 dual 1.75" carbs weight drops to 1940 lbs; triple Weber 40 DCOE options consolidated.

As printed in Fastrack

In EP spec line, Triumph GT6, make the following change in the Notes section:
"Two (2) 1.75” auto-type carburetors @ 1970 40 lbs. Three (3) Weber 40 DCOE on IR manifold with 28mm chokes @ 1990
lbs. Laycock overdrive, May use 5 speed gearbox w/o overdrive. ~~Three (3) Weber 40mm DCOE w/28mm venturi on individual~~
~~runner manifold @ 2020 lb.~~"

2024-01-01 EP Triumph GT6 Adjustments

#35255 from Anthony Parker · Rule change · TB 24-01 (2024-01 Fastrack)

Summary

fasterEP Triumph GT6 dual 1.75" carbs weight drops to 1940 lbs; triple Weber 40 DCOE options consolidated.

As printed in Fastrack

2024-01-01 FP Honda S2000 throttle body

#35272 from Aaron Johnson · Rule change · TB 24-01 (2024-01 Fastrack)

Summary

fasterEP Honda S2000 fuel injected throttle body inside diameter increases from 62mm to 64mm.

As printed in Fastrack

In EP spec line, Honda S2000, make the following changes to its spec line:
Fuel Injected Equipped Throttle Body Inside Diameter: "62 64"
Notes: "Comp. Ratio limited to 12.0:1. Valve lift limited to .500”. An adaptor plate can be used to mount the 62mm throttle body
from '00-05 to the '06-09 intake manifold. The adaptor plate can be no more than 1.25" thick, and its bore must not exceed the
"Fuel Injected Equipped Throttle Body Inside Diameter" maximum spec of 64mm."

2024-01-01 EP Honda S2000 throttle body

#35272 from Aaron Johnson · Rule change · TB 24-01 (2024-01 Fastrack)

Summary

fasterEP Honda S2000 fuel injected throttle body inside diameter increases from 62mm to 64mm.

As printed in Fastrack

2024-01-01 FP Correction within Triumph TR8 Spec Line

#35315 from Production Committee · Rule change · TB 24-01 (2024-01 Fastrack)

Summary

wordingEP Triumph TR8 dry sump allowance moved from carburetor line to notes section.

As printed in Fastrack

In EP spec line, Triumph TR8 (78-81), move the "Dry sump allowed" wording to the appropriate location as follows:
Carburetor. No. & Type: “Zenith Stromberg carbs or fuel injection. ~~Dry sump is allowed.~~”
Notes: “Comp. Ratio limited to 12.0:1, Valve lift limited to .500”. Dry sump is allowed.”

2024-01-01 EP Correction within Triumph TR8 Spec Line

#35315 from Production Committee · Rule change · TB 24-01 (2024-01 Fastrack)

Summary

wordingEP Triumph TR8 dry sump allowance moved from carburetor line to notes section.

As printed in Fastrack

2024-01-01 FP Correction to EP 924S/944 Spec Line

#35317 from Production Committee · Rule change · TB 24-01 (2024-01 Fastrack)

Summary

wordingEP Porsche 944/924S 2.5L and 2.7L weight minimums corrected: 2479cc to 2306/2363 lbs, 2681cc to 2358/2415 lbs.

As printed in Fastrack

In EP spec line, Porsche 944/924S 2.5L (2V) / 2.7L (2V) (83-89), change Weight as follows:

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

2024-01-01 EP Correction to EP 924S/944 Spec Line

#35317 from Production Committee · Rule change · TB 24-01 (2024-01 Fastrack)

Summary

wordingEP Porsche 944/924S 2.5L and 2.7L weight minimums corrected: 2479cc to 2306/2363 lbs, 2681cc to 2358/2415 lbs.

As printed in Fastrack

In EP spec line, Porsche 944/924S 2.5L (2V) / 2.7L (2V) (83-89), change Weight as follows:

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

2024-02-01 FP Update 1988-1991 Civic to Match 1988-1991 CRX

#35399 from Enrik Benazic · Rule change · TB 24-02 (2024-01 Fastrack)

Summary

fasterHP Honda Civic 1.5 (88-91) weight reduced to 2175 lbs base, 2229 lbs with power adder, 2284 lbs with two.

As printed in Fastrack

In HP, make the following weight change:
Honda Civic 1.5 (88-91)
~~“2245~~ 2175
*~~2301~~ 2229
**~~2357~~ 2284”

2024-02-01 EP Update 1988-1991 Civic to Match 1988-1991 CRX

#35399 from Enrik Benazic · Rule change · TB 24-02 (2024-01 Fastrack)

Summary

fasterHP Honda Civic 1.5 (88-91) weight reduced to 2175 lbs base, 2229 lbs with power adder, 2284 lbs with two.

As printed in Fastrack

In HP, make the following weight change:
Honda Civic 1.5 (88-91)
~~“2245~~ 2175
*~~2301~~ 2229
**~~2357~~ 2284”

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

2024-03-01 FP GCR Correction - Redundant HP Spec Lines

#35623 from Production Committee · Rule change · TB 24-03 (2024-03 Fastrack)

Summary

wordingHP removes four redundant VW spec lines: Rabbit Cabriolet 1780, Scirocco 1588, Scirocco 1780 8-valve, Scirocco 1588.

As printed in Fastrack

In HP Spec Lines, delete the following redundant spec lines in their entirety:
Spec line #10 - VW Rabbit Cabriolet 1780
Spec line #3 - VW Scirocco 1588
Spec line #4 - VW Scirocco 1780 (8-valve) (83-88)
Spec line #5 - VW Scirocco 1588

2024-03-01 EP GCR Correction - Redundant HP Spec Lines

#35623 from Production Committee · Rule change · TB 24-03 (2024-03 Fastrack)

Summary

wordingHP removes four redundant VW spec lines: Rabbit Cabriolet 1780, Scirocco 1588, Scirocco 1780 8-valve, Scirocco 1588.

As printed in Fastrack

2024-03-01 FP Update FP Protege (01-03) Model Info

#35715 from Production Committee · Rule change · TB 24-03 (2024-03 Fastrack)

Summary

wordingFP Mazda Protégé ES (01-03) model designation updated to include /5 variant.

As printed in Fastrack

In FP Spec Lines, Mazda Protégé ES (01-03) change vehicle as follows:
"Mazda Protégé ES/5 (01-03)"

2024-05-01 FP Request to Replace CRX Plastic Panels

#35876 from Darryl Saylor · Rule change · TB 24-05 (2024-05 Fastrack)

Summary

wordingFP Honda CRX 84-87 can replace plastic front header, rocker skirt, door cap panels with stock-appearance replicas in alternate materials.

As printed in Fastrack

In FP spec line "Honda CRX / CRX Si (84-87)", add the following wording to the Notes section:
"The plastic OE front header/nose body panel, lower rocker side-skirt, and lower door cap panel can be replaced by a
replica, which may be constructed of an alternate material, provided its appearance remains stock."

2024-05-01 FP FP data and parity

#35896 from Production Committee · Rule change · TB 24-05 (2024-05 Fastrack)

Summary

slowerFP Acura Integra and Honda Civic models now require 55mm Flat Plate Intake Restrictor.

As printed in Fastrack

In the following FP spec lines, add the following wording to the Notes section:
Acura Integra (90-93)
Acura Integra LS (94-01)
Acura Integra GSR (92-93)
Honda Civic Del Sol VTEC (94-97)
Honda Civic Si (99-00)
"55mm Flat Plate Intake Restrictor is required."

2024-06-01 FP NIssan 300ZX Z31 to EP

#35830 from Murphy Nichols · Rule change · TB 24-06 (2024-06 Fastrack)

Summary

cars addedNissan 300ZX 84-89 classified to EP at 2550 lbs minimum, 2960cc 6-cyl SOHC, fuel injection, 12.0:1 compression limit, 0.500" valve lift limit.

As printed in Fastrack

In EP Spec Lines, classify Nissan 300ZX (84-89), as follows:

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

2024-06-01 EP NIssan 300ZX Z31 to EP

#35830 from Murphy Nichols · Rule change · TB 24-06 (2024-06 Fastrack)

Summary

cars addedNissan 300ZX 84-89 classified to EP at 2550 lbs minimum, 2960cc 6-cyl SOHC, fuel injection, 12.0:1 compression limit, 0.500" valve lift limit.

As printed in Fastrack

In EP Spec Lines, classify Nissan 300ZX (84-89), as follows:

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

2024-06-01 FP RX7 1993 and Up Request In EP Spec Lines, classify

#36031 from Edward Zabinski · Rule change · TB 24-06 (2024-06 Fastrack)

Summary

cars addedMazda RX-7 92-97 newly classified EP Prep Level 2 at 2200–2310 lbs with 13B 6-port rotary engine.

As printed in Fastrack

Mazda RX-7 (92-97) as follows:

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

2024-06-01 EP RX7 1993 and Up Request In EP Spec Lines, classify

#36031 from Edward Zabinski · Rule change · TB 24-06 (2024-06 Fastrack)

Summary

cars addedMazda RX-7 92-97 newly classified EP Prep Level 2 at 2200–2310 lbs with 13B 6-port rotary engine.

As printed in Fastrack

Mazda RX-7 (92-97) as follows:

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

2024-06-01 FP Clean-up Multiple EP RX-8 Spec Lines In EP

#36156 from Production Committee · Rule change · TB 24-06 (2024-06 Fastrack)

Summary

wordingEP Mazda RX-8 (04-11) alternate spec line removed; one primary line remains.

As printed in Fastrack

Spec Lines, make the following changes to the two Mazda RX-8 spec lines.
Remove spec line entirely:
~~Mazda RX-8 (04-11)~~
Remove the wording "alternate":
Mazda RX-8 (04-11)~~(alternate)~~
Spec Mazda (SM/SMX) None.

2024-06-01 EP Clean-up Multiple EP RX-8 Spec Lines In EP

#36156 from Production Committee · Rule change · TB 24-06 (2024-06 Fastrack)

Summary

wordingEP Mazda RX-8 (04-11) alternate spec line removed; one primary line remains.

As printed in Fastrack

2024-08-01 FP Errant entry in HP production line item

#36231 from Angus Crome · Rule change · TB 24-08 (2024-08 Fastrack)

Summary

wordingHP Volkswagen Golf and Jetta 85-92 track correction: front 1537mm (60.5in), rear 1529mm (60.2in).

As printed in Fastrack

In HP Spec Lines, change Track (F/R)mm/(in.) as follows:
Volkswagen Golf (GTI, GT, GL) (85-92): "2 1537/1529 (60.5/60.2)"
Volkswagen Jetta (GLI, GL) (85-92): "2 1537/1529 (60.5/60.2)"

2024-08-01 EP Errant entry in HP production line item

#36231 from Angus Crome · Rule change · TB 24-08 (2024-08 Fastrack)

Summary

wordingHP Volkswagen Golf and Jetta 85-92 track correction: front 1537mm (60.5in), rear 1529mm (60.2in).

As printed in Fastrack

In HP Spec Lines, change Track (F/R)mm/(in.) as follows:
Volkswagen Golf (GTI, GT, GL) (85-92): "2 1537/1529 (60.5/60.2)"
Volkswagen Jetta (GLI, GL) (85-92): "2 1537/1529 (60.5/60.2)"

2024-10-01 FP Errors/emissions Honda Civic/CRX

#36700 from Martin Burk · Rule change · TB 24-10 (2024-10 Fastrack)

Summary

fasterFP Honda CRX/CRX Si 84-87 block material changes from Iron to Alum.

As printed in Fastrack

In FP Spec Lines, Honda CRX / CRX Si (84-87), change Block Mat'l as follows:
"~~Iron~~ Alum"

2024-11-01 FP 1275 HP Spridget Level 2 Only

#36518 from Darryl Saylor · Rule change · TB 24-09 (2024-09 Fastrack)

Summary

fasterHP Sprite and Midget 1275cc and 1098cc Level 2 compression ratio raised to 12.0:1.

As printed in Fastrack

In HP Spec Lines, Austin-Healey Sprite MkI, II, III, IV MG Midget (ALL) - Level 2 - 1275cc, change Notes as follows:
"(Effective 11/1/2024) Compression ratio limited to 11 12.0:1"
In HP Spec Lines, Austin-Healey Sprite MkI, II, III, IV MG Midget (ALL) - Level 2 - 1098cc, change Notes as follows:
"(Effective 11/1/2024) Compression ratio limited to 11 12.0:1"

2024-11-01 EP 1275 HP Spridget Level 2 Only

#36518 from Darryl Saylor · Rule change · TB 24-09 (2024-09 Fastrack)

Summary

fasterHP Sprite and Midget 1275cc and 1098cc Level 2 compression ratio raised to 12.0:1.

As printed in Fastrack

2024-11-01 EP NA Miata Track Width Correction

#36902 from Production Committee · Rule change · TB 24-11 (2024-11 Fastrack)

Summary

wordingEP Mazda Miata front and rear track widths increased to 1516/1534 mm (59.7/60.4 in.) across all generations.

As printed in Fastrack

In EP Spec Lines, Track (F/R) mm/(in.), change as follows:
Mazda MX-5 /Miata 1.6L (-1993) - ~~"1478/1491 (58.2/58.7)~~ 1516/1534 (59.7/60.4)"
Mazda MX-5 /Miata 1.8L (90-97) - ~~"1483/1509 (58.4/59.4)~~ 1516/1534 (59.7/60.4)"
Mazda MX-5 /Miata (94-97) - "~~1483/1509 (58.4/59.4)~~ 1516/1534 (59.7/60.4)"

2024-12-01 EP Triumph GT6 Adjustments

#37112 from Anthony Parker · Rule change · TB 24-12 (2024-12 Fastrack)

Summary

slowerEP Triumph GT6 switches to three Weber 40 DCOE carbs with 28mm chokes, weight rises 50 lbs to 1990.

As printed in Fastrack

In EP Spec Lines, make the following changes in the "Triumph GT6" spec line:
Carburetor No. & Type: (2): "~~1.5”~~ 1.75" Auto-type carburetor(s)"
Notes: "~~Two (2) 1.75” auto-type carburetors @ 1940 lbs.~~ Three (3) Weber 40 DCOE on IR manifold with 28mm chokes @ 1990
lbs. Laycock overdrive, May use 5 speed gearbox w/o overdrive."

2025-01-01 FP Request to Reduce Weight of BMW 325i/is E30 (84-91) Spec Line

#37119 from Tim Schreyer · Rule change · TB 25-01 (2025-01 Fastrack)

Summary

fasterEP BMW 325i/is E30 (84-91) weight reduced 50–52 lbs across three spec lines to 2150, 2204, 2258.

As printed in Fastrack

In EP SPEC LINES, BMW 325i/is (E30) (84-91), change Weight as follows:
"~~2200~~ 2150
*~~2255~~ 2204
**~~2310~~ 2258"

2025-01-01 EP Request to Reduce Weight of BMW 325i/is E30 (84-91) Spec Line

#37119 from Tim Schreyer · Rule change · TB 25-01 (2025-01 Fastrack)

Summary

fasterEP BMW 325i/is E30 (84-91) weight reduced 50–52 lbs across three spec lines to 2150, 2204, 2258.

As printed in Fastrack

In EP SPEC LINES, BMW 325i/is (E30) (84-91), change Weight as follows:
"~~2200~~ 2150
*~~2255~~ 2204
**~~2310~~ 2258"

2025-01-01 FP Fix Error in Spridget Spec Line

#37437 from Jason Stine · Rule change · TB 25-01 (2025-01 Fastrack)

Summary

wordingFP Spridget and Midget 1275cc and 1500cc spec line corrections to bore, stroke, displacement, and valve sizes.

As printed in Fastrack

In FP SPEC LINES, Austin-Healey Sprite Mk. I, II,III, IV MG Midget Mk I,II, III, IV & 1500, change the following:
1275cc:
Bore x Stroke: "~~68.1x78.4 (2.68x3.09)~~ 70.6x81.3 (2.78x3.20)"
Displacement: "~~(77.78)~~ 1275"
Valves IN & EX: ~~"(I) 32.1/(1.26) (E) 28.4/(1.12)~~ (I) 33.3/(1.31) (E) 29.5/(1.16)"
1500cc:
Bore x Stroke: "~~1.1x84.3~~ 73.7x87.4 (2.90x3.44)"
Displacement: "~~1491 (90.95)~~ 1493"

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Valves IN & EX: "(I) 36.6/(1.44) (E) ~~28.7~~ 29.7/(1.17)"

2025-01-01 FP Create ruleset that allows GTL cars to run in FP

#37485 from Club Racing Board · Rule change · TB 25-01 (2025-01 Fastrack)

Summary

cars addedF Production now allows GT-Lite cars meeting Appendix N specifications to compete, effective 2025-01-01.

As printed in Fastrack

“~~(Effective January 1, 2026)~~ (Effective January 1, 2025)." Any GT-Lite (GTL) car meeting all of the requirements of Appendix N
GT-LITE CATEGORY SPECIFICATIONS for inclusion into F PRODUCTION" may compete in the F-Production class. For GTL cars
competing in FP, the level of preparation and modifications will be determined by Appendix N and not by PCS 9.1.5.”

2025-02-21 FP Effective date for Jan 2025 GCR updates

#37654 from Doug Piner · Rule change · TB 25-02 (2025-02 Fastrack)

Summary

slowerEP BMW Z3 2.5L requires 52mm flat plate intake restrictor; Z3 2.8L 55mm; 328i/is E36 58mm; 328i/ci E46 58mm; 325i/is E46 56mm; 325i/is E36 56mm; 325is M-Technic 56mm.

As printed in Fastrack

In EP Spec Lines, add to Notes as follows:
BMW Z3 2.5LL "(Effective 2/21/2025) 52mm Flat Plate Intake Restrictor is required."
BMW Z3 2.8L (97-00): "(Effective 2/21/2025) 55mm Flat Plate Intake Restrictor is required."
BMW 328i/is E36 (96-99): "(Effective 2/21/2025) 58mm Flat Plate Intake Restrictor is required."
BMW 328i/ci E46 (01-06): "(Effective 2/21/2025) 58mm Flat Plate Intake Restrictor is required."
BMW 325i/is E46 (01-06): "(Effective 2/21/2025) 56mm Flat Plate Intake Restrictor is required."
BMW 325i/is E-36 (92-95): "(Effective 2/21/2025) 56mm Flat Plate Intake Restrictor is required."
BMW 325is M-Technic (1994): "(Effective 2/21/2025) 56mm Flat Plate Intake Restrictor is required."

2025-02-21 EP Effective date for Jan 2025 GCR updates

#37654 from Doug Piner · Rule change · TB 25-02 (2025-02 Fastrack)

Summary

slowerEP BMW Z3 2.5L requires 52mm flat plate intake restrictor; Z3 2.8L 55mm; 328i/is E36 58mm; 328i/ci E46 58mm; 325i/is E46 56mm; 325i/is E36 56mm; 325is M-Technic 56mm.

As printed in Fastrack

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

2025-03-01 FP Request Competition Adjustment to BMW Z3 2.5L

#37120 from Tim Schreyer · Rule change · TB 25-01 (2025-01 Fastrack)

Summary

slowerEP BMW Z3 and 3-series models get smaller intake restrictors: Z3 2.5L to 52mm, Z3 2.8L to 55mm, 328i to 58mm, 325i to 56mm.

As printed in Fastrack

In EP Spec Lines, change Notes as follows:
BMW Z3 2.5LL "(Effective 3/1/2025) ~~56mm~~ 52mm Flat Plate Intake Restrictor is required."
BMW Z3 2.8L (97-00): "(Effective 3/1/2025) ~~59mm~~ 55mm Flat Plate Intake Restrictor is required."
BMW 328i/is E36 (96-99): "(Effective 3/1/2025) ~~62mm~~ 58mm Flat Plate Intake Restrictor is required."
BMW 328i/ci E46 (01-06): "(Effective 3/1/2025) ~~62mm~~ 58mm Flat Plate Intake Restrictor is required."
BMW 325i/is E46 (01-06): "(Effective 3/1/2025) ~~60mm~~ 56mm Flat Plate Intake Restrictor is required."
BMW 325i/is E-36 (92-95): "(Effective 3/1/2025) ~~60mm~~ 56mm Flat Plate Intake Restrictor is required."
BMW 325is M-Technic (1994): "(Effective 3/1/2025) ~~60mm~~ 56mm Flat Plate Intake Restrictor is required."

2025-03-01 EP Request Competition Adjustment to BMW Z3 2.5L

#37120 from Tim Schreyer · Rule change · TB 25-01 (2025-01 Fastrack)

Summary

slowerEP BMW Z3 and 3-series models get smaller intake restrictors: Z3 2.5L to 52mm, Z3 2.8L to 55mm, 328i to 58mm, 325i to 56mm.

As printed in Fastrack

2025-03-01 FP Interpretation of Production Rules on Mirrors

#37235 from Lawrence Slivinski · Rule change · TB 25-03 (2025-03 Fastrack)

Summary

wordingEP, FP, HP: interior or exterior mirrors meeting rule 9.3.36 now permitted.

As printed in Fastrack

In GCR, add new rule as Section 9.1.5.E.10.f:
"Any interior or exterior mirror(s) that meets rule 9.3.36 may be used."

2025-03-01 EP Interpretation of Production Rules on Mirrors

#37235 from Lawrence Slivinski · Rule change · TB 25-03 (2025-03 Fastrack)

Summary

wordingEP, FP, HP: interior or exterior mirrors meeting rule 9.3.36 now permitted.

As printed in Fastrack

In GCR, add new rule as Section 9.1.5.E.10.f:
"Any interior or exterior mirror(s) that meets rule 9.3.36 may be used."

2025-03-01 FP FP Class Adjustments

#37458 from Production Committee · Rule change · TB 25-01 (2025-01 Fastrack)

Summary

slowerFP Acura Integra and Honda Civic models get smaller 51mm intake restrictors, down from 55mm; Del Sol VTEC weight increases to 2290–2405 lbs.

As printed in Fastrack

In FP SPEC LINES, change Notes as follows:
Acura Integra (90-93): "(Effective 3/1/2025) ~~55mm~~ 51mm Flat Plate Intake Restrictor is required."
Acura Integra LS (94-01): "(Effective 3/1/2025) ~~55mm~~ 51mm Flat Plate Intake Restrictor is required."
Acura Integra GSR (92-93): "(Effective 3/1/2025) ~~55mm~~ 51mm Flat Plate Intake Restrictor is required."
Honda Civic Si (99-00): "(Effective 3/1/2025) ~~55mm~~ 51mm Flat Plate Intake Restrictor is required.
In FP SPEC LINES, change as follows:
Honda Civic Del Sol VTEC (94-97): "
Weight: "(Effective 3/1/2025) ~~2265 *2322 **2378~~ 2290 *2347 **2405

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Notes: "(Effective 3/1/2025) ~~55mm~~ 51mm Flat Plate Intake Restrictor is required."

2025-03-01 FP Weight Reduction for Honda S2000

#37466 from Michael Unger · Rule change · TB 25-03 (2025-03 Fastrack)

Summary

fasterEP Honda S2000 1997cc base loses 75 lbs to 2375; 2157cc base loses 60 lbs to 2450.

As printed in Fastrack

In EP, Spec Lines make the following weight changes:

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

2025-03-01 EP Weight Reduction for Honda S2000

#37466 from Michael Unger · Rule change · TB 25-03 (2025-03 Fastrack)

Summary

fasterEP Honda S2000 1997cc base loses 75 lbs to 2375; 2157cc base loses 60 lbs to 2450.

As printed in Fastrack

In EP, Spec Lines make the following weight changes:

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

2025-03-01 FP Mazda 1999 Miata 1.8L

#37488 from Joe Carr · Rule change · TB 25-03 (2025-03 Fastrack)

Summary

fasterEP Mazda MX-5/Miata 99-05 minimum weight drops to 2100 lbs, 2153 lbs with power adder, 2205 lbs with two adders.

As printed in Fastrack

In EP Spec Lines, make the following weight change:
Mazda MX-5 /Miata (99-05):
"~~2150~~ 2100
*~~2204~~ 2153
**~~2258~~ 2205"

2025-03-01 EP Mazda 1999 Miata 1.8L

#37488 from Joe Carr · Rule change · TB 25-03 (2025-03 Fastrack)

Summary

fasterEP Mazda MX-5/Miata 99-05 minimum weight drops to 2100 lbs, 2153 lbs with power adder, 2205 lbs with two adders.

As printed in Fastrack

In EP Spec Lines, make the following weight change:
Mazda MX-5 /Miata (99-05):
"~~2150~~ 2100
*~~2204~~ 2153
**~~2258~~ 2205"

2025-03-01 FP Errors & Omissions

#37648 from Bryan Floyd · Rule change · TB 25-03 (2025-03 Fastrack)

Summary

cars addedFP GTL Volkswagen Jetta Mark IV 4dr FWD 98.2 wheelbase newly classified.

As printed in Fastrack

In FP Spec Lines, Appendix N, GTL-FP Cars - Volkswagen, classify Jetta Mark - IV as follows:
GTL-FP Cars - VOLKSWAGEN
Model Years Body Style Drive-line Wheelbase (in) Notes
Jetta Mark - IV 4dr FWD 98.2

2025-03-01 FP GTL/FP consolidation 2025 Rules

#37659 from James Gregorius · Rule change · TB 25-03 (2025-03 Fastrack)

Summary

inductionFP Spec Lines option: carburettor chokes permitted as alternative to SIR, same size as listed SIR.

As printed in Fastrack

In FP Spec Lines, Appendix N: L.9, Fuel Injection System, add the following:
"As an option, induction system “Chokes” may be used where a SIR is required. Said chokes shall be fitted to each barrel of
carburetor/throttle body and all airflow into engine must pass through them. Choke size will be the same as listed SIR unless
noted."

2025-03-01 GT3U 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 FP Request for Classification of Chevrolet Spark

#37755 from Kristian Smith · Rule change · TB 25-04 (2025-04 Fastrack)

Summary

cars addedChevrolet Spark 16-22 classified HP Pre at 1850 lbs minimum weight, fuel injected, 1399 cc.

As printed in Fastrack

In HP Spec Lines, classify the Chevrolet Spark (16-22):

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

2025-04-01 EP Request for Classification of Chevrolet Spark

#37755 from Kristian Smith · Rule change · TB 25-04 (2025-04 Fastrack)

Summary

cars addedChevrolet Spark 16-22 classified HP Pre at 1850 lbs minimum weight, fuel injected, 1399 cc.

As printed in Fastrack

In HP Spec Lines, classify the Chevrolet Spark (16-22):

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

2025-04-01 FP Request to Lower Ford Festiva Minimum Weight to 1600 LBS

#37939 from Doug DeRonne · Rule change · TB 25-04 (2025-04 Fastrack)

Summary

fasterHP Ford Festiva 88-93 minimum weight drops to 1600 lbs, variants to 1640 and 1680 lbs; compression ratio raised to 11.0:1.

As printed in Fastrack

In HP Spec Lines "Ford Festiva (88-93)" change as follows:
Weight:
"~~1700~~ 1600
*~~1743~~ 1640
**~~1785~~ 1680"
Notes:
"Compression ratio limited to ~~10.5~~ 11.0:1. Valve lift limited to .450”."

2025-04-01 EP Request to Lower Ford Festiva Minimum Weight to 1600 LBS

#37939 from Doug DeRonne · Rule change · TB 25-04 (2025-04 Fastrack)

Summary

fasterHP Ford Festiva 88-93 minimum weight drops to 1600 lbs, variants to 1640 and 1680 lbs; compression ratio raised to 11.0:1.

As printed in Fastrack

In HP Spec Lines "Ford Festiva (88-93)" change as follows:
Weight:
"~~1700~~ 1600
*~~1743~~ 1640
**~~1785~~ 1680"
Notes:
"Compression ratio limited to ~~10.5~~ 11.0:1. Valve lift limited to .450”."

2025-04-01 GT3U TCR Rulesets

#37981 from Club Racing Board · Rule change · TB 25-04 (2025-04 Fastrack)

Summary

fasterSTU-GT3U non-TCR cars may reduce weight by 4% after all other modifiers.

As printed in Fastrack

In STU-GT3U Spec Lines, Table C, add the following:
"Table C: STU-GT3U
Refer to section 9.1.2."
In GCR, Section 9.1.4.H.7, change as follows:
"All current STU cars, except TCR cars, may reduce their weight by 4% after all other modifiers"

2025-05-01 GT3U 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

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including the 225 lbs."

2025-06-01 FP Base Weight Adjustment for H-Production X1/9 Spec Lines

#38255 from Matthew Brannon · Rule change · TB 25-06 (2025-06 Fastrack)

Summary

fasterHP Fiat X-1/9 base weights reduced 50–53 lbs across 1300 and 1500 spec lines.

As printed in Fastrack

In HP Spec Lines, change Weight as follows:
Fiat X-1/9 & Bertone1500: “~~1790~~ 1740 *~~1835~~ 1784 **~~1880~~ 1827”
Fiat X-1/9 1300: “~~1650~~ 1600 *~~1691~~ 1640 **~~1733~~ 1680”
Fiat X-1/9 1300: “~~2060~~ 2010”
Fiat X-1/9 1500: “~~1950~~ 1900”

2025-06-01 EP Base Weight Adjustment for H-Production X1/9 Spec Lines

#38255 from Matthew Brannon · Rule change · TB 25-06 (2025-06 Fastrack)

Summary

fasterHP Fiat X-1/9 base weights reduced 50–53 lbs across 1300 and 1500 spec lines.

As printed in Fastrack

2025-07-01 FP BMW Z4 update

#38490 from Bryce McGuire · Rule change · TB 25-07 (2025-07 Fastrack)

Summary

slowerEP BMW Z4 03-05 restricted to 52mm flat plate intake restrictor.

As printed in Fastrack

In EP Spec Lines, BMW Z4 (03-05), add to Notes the following:
“52mm Flat Plate Intake Restrictor.”

2025-07-01 EP BMW Z4 update

#38490 from Bryce McGuire · Rule change · TB 25-07 (2025-07 Fastrack)

Summary

slowerEP BMW Z4 03-05 restricted to 52mm flat plate intake restrictor.

As printed in Fastrack

In EP Spec Lines, BMW Z4 (03-05), add to Notes the following:
“52mm Flat Plate Intake Restrictor.”

2025-07-01 FP EP Fiat 124 Spider Competition Adjustment Request

#38498 from John Baucom · Rule change · TB 25-07 (2025-07 Fastrack)

Summary

fasterEP Fiat 124 Spider 1600 & 2000 weight drops 50 lbs to 2000; carburetors gain 2mm chokes to 36mm.

As printed in Fastrack

In EP Spec Lines, Fiat 124 Sport Spider 1600 & 124 Spider 2000, change as follows:
Weight: "~~2050~~ 2000"
Carburetor No. & Type: "(2) Weber 40 IDF-40IFI, (2) Solex C40P116, 34 36mm choke(s) req’d, (2) Weber 45DCOE w/ 34 36 mm
choke(s) on I.R. manifold or fuel injection."

2025-07-01 EP EP Fiat 124 Spider Competition Adjustment Request

#38498 from John Baucom · Rule change · TB 25-07 (2025-07 Fastrack)

Summary

fasterEP Fiat 124 Spider 1600 & 2000 weight drops 50 lbs to 2000; carburetors gain 2mm chokes to 36mm.

As printed in Fastrack

2025-10-01 FP HP Plymouth Arrow spec omission

#38995 from Production Committee · Rule change · TB 25-10 (2025-10 Fastrack)

Summary

wordingHP Plymouth Arrow transmission max speeds clarified to 4 or 5.

As printed in Fastrack

In HP Spec Lines, Plymouth Arrow (76-80), add the following wording to Trans. Speeds(max):
"4 or 5"

2025-10-01 EP HP Plymouth Arrow spec omission

#38995 from Production Committee · Rule change · TB 25-10 (2025-10 Fastrack)

Summary

wordingHP Plymouth Arrow transmission max speeds clarified to 4 or 5.

As printed in Fastrack

In HP Spec Lines, Plymouth Arrow (76-80), add the following wording to Trans. Speeds(max):
"4 or 5"

2025-10-01 FP Add Wheel Diameter to Appendix G

#39008 from Production Committee · Rule change · TB 25-10 (2025-10 Fastrack)

Summary

wordingEP, FP, HP wheel diameter added to Appendix G as absolute maximum specification.

As printed in Fastrack

In Appendix G.2.3, change as follows:
"Rim width and diameter are is absolute maximums."

2025-10-01 EP Add Wheel Diameter to Appendix G

#39008 from Production Committee · Rule change · TB 25-10 (2025-10 Fastrack)

Summary

wordingEP, FP, HP wheel diameter added to Appendix G as absolute maximum specification.

As printed in Fastrack

In Appendix G.2.3, change as follows:
"Rim width and diameter are is absolute maximums."

2025-10-01 FP Add TB ID tolerance to general Prod rules

#39009 from Production Committee · Rule change · TB 25-10 (2025-10 Fastrack)

Summary

wordingEP, FP, HP throttle body inside dimensions must remain stock with +/-.25mm tolerance; butterfly dimensions stock in FP, HP only.

As printed in Fastrack

In GCR, Section 9.1.5.E., change as follows:
9.1.5.E.1.b.4: "The inside dimensions of the throttle body casting/housing (as measured at the throttle butterfly) must remain
stock (tolerance of +/-.25mm), but the throttle body can otherwise be ported and polished."
9.1.5.E.2.b.4: "The inside dimensions of the throttle body casting/housing and all dimensions of the throttle butterfly must
remain stock (tolerance of +/-.25mm)."

2025-10-01 EP Add TB ID tolerance to general Prod rules

#39009 from Production Committee · Rule change · TB 25-10 (2025-10 Fastrack)

Summary

wordingEP, FP, HP throttle body inside dimensions must remain stock with +/-.25mm tolerance; butterfly dimensions stock in FP, HP only.

As printed in Fastrack

2025-11-01 FP Please Lower Weight of 280Z

#38871 from Matthew Miller · Rule change · TB 25-09 (2025-09 Fastrack)

Summary

fasterEP Nissan 280Z minimum weight reduced from 2560 to 2400 lbs.

As printed in Fastrack

In EP Spec Lines, Nissan 280Z, change Weight (lbs) as follows:
"(Effective 11/1/2025) ~~2560~~ 2400
*~~2624~~ 2460
**~~2688~~ 2520"

2025-11-01 EP Please Lower Weight of 280Z

#38871 from Matthew Miller · Rule change · TB 25-09 (2025-09 Fastrack)

Summary

fasterEP Nissan 280Z minimum weight reduced from 2560 to 2400 lbs.

As printed in Fastrack

In EP Spec Lines, Nissan 280Z, change Weight (lbs) as follows:
"(Effective 11/1/2025) ~~2560~~ 2400
*~~2624~~ 2460
**~~2688~~ 2520"

2025-11-01 FP Miata Weight Adjustment Follow Up

#38949 from Don Tucker · Rule change · TB 25-10 (2025-10 Fastrack)

Summary

fasterEP Mazda MX-5 1.8L 90-97 weight reduced to 2125 lbs from 2150 lbs.

As printed in Fastrack

In EP Spec Lines, Mazda MX-5 / Miata 1.8L (90-97), Effective 11/1/2025 make the following weight change:
"~~2150~~ 2125"

2025-11-01 EP Miata Weight Adjustment Follow Up

#38949 from Don Tucker · Rule change · TB 25-10 (2025-10 Fastrack)

Summary

fasterEP Mazda MX-5 1.8L 90-97 weight reduced to 2125 lbs from 2150 lbs.

As printed in Fastrack

In EP Spec Lines, Mazda MX-5 / Miata 1.8L (90-97), Effective 11/1/2025 make the following weight change:
"~~2150~~ 2125"

2025-11-01 FP Weight Break for 1098 Midget / Sprite

#38970 from Kendall Jones · Rule change · TB 25-10 (2025-10 Fastrack)

Summary

fasterHP Austin-Healey Sprite/Midget 1098cc minimum weight drops 80 lbs to 1550.

As printed in Fastrack

In HP Spec Lines, Austin-Healey Sprite/Midget 1098cc, Effective 11/1/2025make the following weight change:
"~~1630~~ 1550"

2025-11-01 EP Weight Break for 1098 Midget / Sprite

#38970 from Kendall Jones · Rule change · TB 25-10 (2025-10 Fastrack)

Summary

fasterHP Austin-Healey Sprite/Midget 1098cc minimum weight drops 80 lbs to 1550.

As printed in Fastrack

In HP Spec Lines, Austin-Healey Sprite/Midget 1098cc, Effective 11/1/2025make the following weight change:
"~~1630~~ 1550"

2025-11-01 FP HP Volvo 142 spec omission

#38994 from Production Committee · Rule change · TB 25-10 (2025-10 Fastrack)

Summary

slowerHP Volvo 142/142E gains compression ratio limit 12.0:1 and valve lift limit .425".

As printed in Fastrack

In HP Spec Lines, Volvo 142/142E P-1800 Engine, Effective 11/1/2025 add the following wording to Notes:
"Comp. Ratio limited to 12.0:1. Valve lift limited to .425”."

2025-11-01 EP HP Volvo 142 spec omission

#38994 from Production Committee · Rule change · TB 25-10 (2025-10 Fastrack)

Summary

slowerHP Volvo 142/142E gains compression ratio limit 12.0:1 and valve lift limit .425".

As printed in Fastrack

In HP Spec Lines, Volvo 142/142E P-1800 Engine, Effective 11/1/2025 add the following wording to Notes:
"Comp. Ratio limited to 12.0:1. Valve lift limited to .425”."

2025-11-01 FP HP Mini DOHC 1.6

#38996 from Production Committee · Rule change · TB 25-10 (2025-10 Fastrack)

Summary

slowerHP Mini Cooper 07-15 valve lift reduced to .390", from .450".

As printed in Fastrack

In HP Spec Lines, Mini Cooper (07-13) (includes 09-15 convertible and 12-15 Coupe), Effective 11/1/2025 make the following
changes to the Notes:
"Compression ratio limited to 11.0:1, Valve lift limited to ~~.450”~~.390"."

2025-11-01 EP HP Mini DOHC 1.6

#38996 from Production Committee · Rule change · TB 25-10 (2025-10 Fastrack)

Summary

slowerHP Mini Cooper 07-15 valve lift reduced to .390", from .450".

As printed in Fastrack

2025-11-01 FP 83-88 FP Scirocco Spec Line Creation

#38997 from Production Committee · Rule change · TB 25-11 (2025-11 Fastrack)

Summary

cars addedFP Scirocco 83-88 established as spec line with 1733–1803 lbs, 1715–1780 cc SOHC, 40/33 mm valves, Solex carbs or fuel injection.

As printed in Fastrack

In FP Spec Lines, classify Volkswagen Scirocco (83-88) as follows:

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

2025-11-01 FP Add to Rabbit description

#39019 from Production Committee · Rule change · TB 25-11 (2025-11 Fastrack)

Summary

wordingFP and HP Volkswagen Rabbit descriptions updated: Convertible changed to Cabriolet in FP; Cabriolet added to three HP engine variants.

As printed in Fastrack

In FP Spec Lines, make the following spec line correction:
"Volkswagen Rabbit (Includes ~~Convertible~~ Cabriolet)"
In HP Spec Lines, make the following spec line correction:
"Volkswagen Rabbit 1588 (Includes Cabriolet)"
"Volkswagen Rabbit 1715 (Includes Cabriolet)"
"Volkswagen Rabbit 1780 (Includes Cabriolet)"

2025-11-01 EP Add to Rabbit description

#39019 from Production Committee · Rule change · TB 25-11 (2025-11 Fastrack)

Summary

wordingFP and HP Volkswagen Rabbit descriptions updated: Convertible changed to Cabriolet in FP; Cabriolet added to three HP engine variants.

As printed in Fastrack

2025-11-01 FP Clean-up 9.1.5.E.7e

#39025 from Production Committee · Rule change · TB 25-11 (2025-11 Fastrack)

Summary

wordingEP, FP, HP: rear drum brake to disc conversion clarified; rotors solid, diameter limited to largest front rotor permitted.

As printed in Fastrack

In GCR, Section 9.1.5.E.7., change as follows:
"e. Cars fitted with rear drum brakes, can convert to rear disc brakes without penalty. N~~ote that the “Brakes Std.” and “Brakes~~
~~Alt.” listings on a vehicle’s spec line do not prohibit a car that was fitted with rear drum brakes stock, from converting to rear~~
~~disc brakes under this rule~~. When converting from rear drum brakes to rear disc brakes:
1. Rear brake rotors must be solid and can be no larger in diameter than the largest permitted front brake rotor, as defined on
the vehicle’s spec line.
2. Rear calipers and mounting brackets are unrestricted but must be made of a ferrous or aluminum material. ~~The standard and~~
~~alternate brake listings on a vehicle’s specification line, does not prohibit a car that was fitted with rear drum brakes as stock~~

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~~from converting to rear disc brakes under this rule.~~
3. The “Brakes Std.” and “Brakes Alt.” listings on a vehicle’s spec line do not prohibit a car that was fitted with rear drum brakes
as stock from converting to rear disc brakes under this rule."

2025-11-01 EP Clean-up 9.1.5.E.7e

#39025 from Production Committee · Rule change · TB 25-11 (2025-11 Fastrack)

Summary

wordingEP, FP, HP: rear drum brake to disc conversion clarified; rotors solid, diameter limited to largest front rotor permitted.

As printed in Fastrack

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2025-11-01 FP Add TB size to Ford Mustang (94-98) Spec Line

#39130 from Production Committee · Rule change · TB 25-11 (2025-11 Fastrack)

Summary

wordingEP Ford Mustang (94-98) fuel injected throttle body inside diameter specified at 60.

As printed in Fastrack

In EP Spec Lines, Ford Mustang (94-98) add the following to the Fuel Injected Equipped Throttle Body Inside Diameter column:
"60"

2025-11-01 EP Add TB size to Ford Mustang (94-98) Spec Line

#39130 from Production Committee · Rule change · TB 25-11 (2025-11 Fastrack)

Summary

wordingEP Ford Mustang (94-98) fuel injected throttle body inside diameter specified at 60.

As printed in Fastrack

In EP Spec Lines, Ford Mustang (94-98) add the following to the Fuel Injected Equipped Throttle Body Inside Diameter column:
"60"

2025-11-01 FP Correct Existing VW Scirocco Spec Line

#39140 from Production Committee · Rule change · TB 25-11 (2025-11 Fastrack)

Summary

fasterFP Volkswagen Scirocco: remove two engine variants (1715cc and 1780cc), lighten one variant to 1663 lbs, allow 15×7 wheels instead of 13×7.

As printed in Fastrack

In FP Spec Lines, Volkswagen Scirocco, change spec line as follows:

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

2025-12-01 FP TR2 Notes E&O

#39180 from Anthony Parker · Rule change · TB 25-12 (2025-12 Fastrack)

Summary

unclearEP Triumph TR2-TR4A allows 5-speed gearbox without overdrive; removes Weber carb and weight specification.

As printed in Fastrack

In EP Spec Lines, Triumph TR2, 3, 3A, 4, 4A, TR4, TR4A, IRS, make the following change to the Notes:
"Front apron assembly may be made of alternate material. ~~Three (3) Weber 40 DCOE on IR manifold with 28mm chokes @ 1990~~
~~lbs.~~ Laycock overdrive, may use 5 speed gearbox without overdrive."

2025-12-01 EP TR2 Notes E&O

#39180 from Anthony Parker · Rule change · TB 25-12 (2025-12 Fastrack)

Summary

unclearEP Triumph TR2-TR4A allows 5-speed gearbox without overdrive; removes Weber carb and weight specification.

As printed in Fastrack

2025-12-01 FP Balance of Power

#39187 from Jim Simaras · Rule change · TB 25-12 (2025-12 Fastrack)

Summary

slowerEP BMW Z3 2.5L restrictor reduced 52mm to 50mm, weight increased to 2550 lbs base; five other BMW models get smaller restrictors.

As printed in Fastrack

In EP Spec Lines, make the following changes to Restrictors:
BMW Z3 2.5L: "~~52mm~~ 50mm Flat Plate Intake Restrictor"
BMW Z3 2.8L (97-00): "~~55mm~~ 53mm Flat Plate Intake Restrictor"
BMW 328i/is E36 (96-99): "~~58mm~~ 55mm Flat Plate Intake Restrictor"
BMW 328i/ci E46 (01-06): "~~58mm~~ 55mm Flat Plate Intake Restrictor"
BMW 325i/is (E46) (01-06): "~~56mm~~ 53mm Flat Plate Intake Restrictor"
BMW 325is M-Technic (1994): "~~56mm~~ 53mm Flat Plate Intake Restrictor"
BMW 325i/is E-36 (92-95): "~~56mm~~ 53mm Flat Plate Intake Restrictor"

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In EP Spec Lines, BMW Z3 2.5L, change Weight as follows:
"~~2500~~ 2550
*~~2563~~ 2614
**~~2625~~ 2678"

2025-12-01 EP Balance of Power

#39187 from Jim Simaras · Rule change · TB 25-12 (2025-12 Fastrack)

Summary

slowerEP BMW Z3 2.5L restrictor reduced 52mm to 50mm, weight increased to 2550 lbs base; five other BMW models get smaller restrictors.

As printed in Fastrack

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In EP Spec Lines, BMW Z3 2.5L, change Weight as follows:
"~~2500~~ 2550
*~~2563~~ 2614
**~~2625~~ 2678"

2025-12-01 FP Competition Adjustment Request

#39259 from David Strittmatter · Rule change · TB 25-12 (2025-12 Fastrack)

Summary

fasterFP Lancia Scorpion minimum weight drops 80 lbs, to 1950.

As printed in Fastrack

In FP Spec Lines, Lancia Scorpion, change Weight as follows:
"~~2030~~ 1950"

2025-12-01 FP Factory Roll Bar Removal on VW Convertible

#39268 from Tim Linerud · Rule change · TB 25-12 (2025-12 Fastrack)

Summary

wordingFP Volkswagen Rabbit Convertible no longer required to remove factory roll bar.

As printed in Fastrack

In FP Spec Line, Volkswagen Rabbit (Includes Convertible), remove the following wording in Notes:
"~~Factory roll bar must be removed on Cabriolet.~~"

2025-12-01 FP FP Parity Request

#39325 from Mason Workman · Rule change · TB 25-12 (2025-12 Fastrack)

Summary

slowerFP Acura Integras and Honda Civics gain 50–79 lbs; Mazda Miata and Mercury Capri compression ratio to 11.0:1, valve lift to .425".

As printed in Fastrack

In FP, change Weight as follows:
Acura Integra (90-93):
"~~2235~~ 2285
*~~2291~~ 2342
**~~2347~~ 2399"
Acura Integra LS (94-01):
"~~2260~~ 2310
*~~2317~~ 2368

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**~~2373~~ 2426"
Acura Integra GSR (92-93):
"~~2325~~ 2375
*~~2383~~ 2434
**~~2441~~ 2494"
Honda Civic Del Sol VTEC (94-97):
"~~2290~~ 2340
*~~2347~~ 2399
**~~2378~~ 2457"
Honda Civic Si (99-00):
"~~2250~~ 2300
*~~2306~~ 2358
**~~2363~~ 2415"
FP Spec Lines, change Notes as follows:
Mazda Miata 1.6L (90-97): "Comp. Ratio limited to ~~10.0:1~~ 11.0:1, Valve lift limited to ~~.390”~~ .425"."
Mercury Capri 1.6L (91-94): "Comp. Ratio limited to ~~10.0:1~~ 11.0:1, Valve lift limited to ~~.390”~~ .425"."

2025-12-01 FP Adjust former-GTL Honda's with B/D-Series Engines

#39374 from Production Committee · Rule change · TB 25-12 (2025-12 Fastrack)

Summary

slowerFP Honda B/D-series engines gain 105–120 lbs minimum weight across seven variants.

As printed in Fastrack

In GCR, Appendix N GTL inclusion into FP, Engines - HONDA, change Disp. (cc) – Weight (lbs) as follows:
"D15 – 1493cc – ~~1895~~ 2000
D15b7 – 1493cc – ~~1895~~ 2000
D16 – 1590cc – ~~1945~~ 2055
D16A – 1590cc – ~~1945~~ 2055
B16A – 1595cc – ~~1950~~ 2065
B18 – 1797cc – ~~2050~~ 2170
B18 – 1834cc – ~~2065~~ 2185"

2026-01-01 EP Request to Update E30 BMW Throttle Body Diameter Verbiage

#39363 from Tim Schreyer · Rule change · TB 26-01 (2026-01 Fastrack)

Summary

wordingEP BMW 325i/is E30 throttle body specified as 60mm in fuel injection notes.

As printed in Fastrack

In EP Spec Line BMW 325i/is E30 (84-91), change Drivetrain Notes as follows:
"Fuel Injection, TB: 60mm"

2026-02-01 FP Request Toyota 5E Series Engines

#38208 from Scott Schick · Rule change · TB 26-02 (2026-02 Fastrack)

Summary

cars addedFP class adds Toyota 5E DOHC 1497cc engine, 1900 lbs minimum weight, 23mm SIR induction.

As printed in Fastrack

In FP Appendix N, add spec line for the Toyota 5E engine to the "Engines - TOYOTA" section:

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

2026-02-01 FP Request for Toyota 4E Series Engines

#38209 from Scott Schick · Rule change · TB 26-02 (2026-02 Fastrack)

Summary

cars addedFP Toyota 4E DOHC 1331cc engine added to Appendix N with 1900 lbs minimum weight.

As printed in Fastrack

In FP Appendix N, add spec line for the Toyota 4E engine to the "Engines - TOYOTA" section:

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

2026-02-01 FP Dual Carbs for the Fiat X1/9

#39593 from Daniel Snow · Rule change · TB 26-02 (2026-02 Fastrack)

Summary

unclearFP Fiat X1/9 gains dual carburetor options with 28mm side-draft alternates and revised valve/transmission specs.

As printed in Fastrack

In FP Spec Lines, change as follows:
Fiat X-1/9 & Bertone 1300:
"(1) Weber 32 DMTR or DATRA/100 w/32mm bores
(1) 40 DCNF w/32mm choke(s)
(2) auto-type side-draft w/28mm choke(s) on I.R. manifold
Orientation of the alternate carburetor is unrestricted. The alternate carb adapter may not be thicker than 1.25”. The adapter
may have a bore larger than the throttle bore of the approved alternate carburetor.
Valve Size: (I) 35.5/(1.40) (E) 31.3/(1.23)~~30.5/(1.20) (E) 1.23~~

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Trans. Speeds: 5"
Fiat X-1/9 & Bertone:
"Fuel Injection
(1) 34 DMTR~~, (1) 36 DCNF w/34mm choke(s), or (1) 40DCNF w/34mm choke(s)~~
(1) 36 or 40 DCNF w/34mm choke(s)
(2) auto-type side-draft w/28mm choke(s) on I.R. manifold
Orientation of the alternate carburetor is unrestricted. The alternate carb adapter may not be thicker than 1.25”. The adapter
may have a bore larger than the throttle bore of the approved alternate carburetor.
Valve Size: (I) 35.5/(1.40) (E) 33.0/(1.30)
Trans. Speeds: 5 or 4"

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