I'm in the process of building a replica group 2 trans am car to eventual run in SVRA group 6TAS. I want to stay as original to the notchback GT350 race cars as Shelby made them. My car is a 67. I'm open to flaring the fenders if that's what Shelby did.
I intend on running DOT tires for now as it will be mostly street with some autocross.
What size wheels and tires did Shelby run?
Does the registry book that's sold her on this site cover the 20-something notchback shelby cars along with full detailed specs?
Thanks!
Eric
According to the 2011 (4th edition) SAAC registry: "Wheels were 15" X 8" front, and 15" X 9"rear, American Racing magnesium wheels. Front and rear had different offsets.
Some cars were shipped with steel 15' X 6" wheels and the buyers were free to use whatever they wanted
Watch the forums "for Sale section for somebody selling this registry. Or Ebay
The registry has 8 plus pages of modification info and photos.
The Group 2 cars raced under the rules in FIA Appendix J. In the first year of Trans Am racing, 1966, Appendix J did not specify specific wheel sizes. Appendix J simply stated that the wheels used had to be the wheels that were supplied by the manufacturer as listed in the Recognition Form approved by the FIA. The 1966 Recognition Form for the Mustang listed wheels sizes as 15 x 7 or 15 x 8.
For 1967, the Recognition Form for the Mustang might be different.
67 FIA appendix j
homologation_form_number_5129_group_1.pdf https://share.google/byxA8bjuwxa9SCoQZ
Roy
From the 67 Group II Bill of Material
Wheels & Tires
2 15" x 8" x 3/8" NEG offset (rear)
2 15"x 7" x 1/8" Pos off set Magnesium wheels (R model)
4 Cobra takeoff tires (English Goodyear)
Here is are a couple pics of the 67 TA Shelby Mustang Car (#12 I think) with the Kode Key Electronics livery restored and vintage raced by the late Walt Boeninger RIP long time member of NorCal Region Shelby Club (SAAC) and former treasurer of the club.
He told me when he restored the car, the correct wheels he could source at the time were the American Magnesium TA wheels from Bud Moore's Team Cougar in 15x8 which he said were "correct" for the Mustang. I really miss Walt. He was a truly good person.
As for current wheels, the only wheels that are identical in appearance to the American Magnesium TA are the ones from Phil Schmidt. The PSE TA one piece rims in 15x8 cast in modern aluminum alloy. Unfortunately the PSE wheels are no longer available.
There is however the magnesium TA wheels from Vintage Engineering. They are ungodly expensive that's if Vic will even make a set for you. They too are in 15x8 with any back spacing you request.
If you come across a preowned set of PSE TA wheels, buy them. But be prepared they will not be cheap.
Happy Holidays,
~Earl J
Here are my set of PSE TA wheels in 15x8 with a 4 3/8" back spacing that Phil recommended. They fit on my car on all four corners. First pic with Goodyear GatorBacks 225/60-15's now with BFG 225's front and 235's rear.
Cheers,
~Earl J
Here are a couple of shots (less than perfect) from back in the day that have been posted in the past.
(https://www.concoursmustang.com/forum/gallery/14/6-101220212627.jpeg)
Was there anything written in the rules for a 67 Coupe to update to the 68 rear flared quarter panels,that would allow a larger wheel & tire? :-\
Any pictures of your 67?
Quote from: EricBohn on November 26, 2025, 04:53:01 PMI'm in the process of building a replica group 2 trans am car to eventual run in SVRA group 6TAS. I want to stay as original to the notchback GT350 race cars as Shelby made them. My car is a 67. I'm open to flaring the fenders if that's what Shelby did.
I intend on running DOT tires for now as it will be mostly street with some autocross.
What size wheels and tires did Shelby run?
Does the registry book that's sold her on this site cover the 20-something notchback shelby cars along with full detailed specs?
Thanks!
Eric
Eric the 67 did not have flares but the 68 TA cars did. Some of the 67 TA cars were brought up to 68 specifacations which there were many. You will have to decide which window in time you want to build Replica.
I believe I remember being in some Cotati races and practice sessions with the Kode Key Mustang. Was it driven "back in the day" by Bob Barker?
Group II was a class spec dictated by the FIA. SCCA used those specs to determine the legality of cars competing in their classes. Shelby was allowed by Ford to build their own TA cars in 1967. They were required to use the specs from Kar Kraft to build their cars. In 68 & 69 Shelby ran cars on loan from Ford and built by Kar Kraft.
TA rules changed each year - The original SCCA GCRs (General Competition Rules) can be found on line for the TransAm series - forgot I had them printed out the scans as a PDF. Flares can be traced directly to horsepower increases needing bigger tire packages. By 73 they were allowing large fiberglass flares but still unibody (full fiberglass fenders, 1/4s, hood and cages from front to rear - more about chassis stiffening than driver protection). When the silhouette cars (full tube) were first built 1980 the only steel part required was the roof panel. In 89 those chassis got full fiberglass sorta looks like a Mustang bodies. Today TransAm is a spec series with 2 levels dictated by sealed engine power levels.
Attached are the 67 & 68 FIA Group II specs for the Mustang.
The primary purpose of Group 2 was to serve as an intermediate class, bridging the gap between Group 1's strictly standard touring cars and the specialized Group 3 GT cars by permitting controlled modifications that enhanced racing capability without departing significantly from road-legal production specifications.[8] This approach maintained a strong connection to everyday road car heritage, encouraging manufacturers to develop affordable, competitive variants that could be raced with minimal deviation from factory builds. By emphasizing close-to-production standards, Group 2 promoted broader manufacturer participation in motorsport, making it accessible for series like touring car championships while ensuring vehicles retained their production lineage
Here is my version of a 67.IMG_1921.jpg
Earl, I really miss Walt and wish that his website for his car and all the TA information could have stayed up. I don't know if anyone saved it or not, Or could put it back up, but it would sure be nice to have.
Walt was the best of the best and the number one club member in Nor Cal SAAC.
Take care and break a leg on the SLOPES, ROY
legendary motorcars has a 1967 TA for sale on their site. #24 of 26 produced. Fred Southerlands car. some great close up photos. :)
Quote from: 98SVT - was 06GT on December 05, 2025, 10:14:08 PMGroup II was a class spec dictated by the FIA. SCCA used those specs to determine the legality of cars competing in their classes. Shelby was allowed by Ford to build their own TA cars in 1967. They were required to use the specs from Kar Kraft to build their cars. In 68 & 69 Shelby ran cars on loan from Ford and built by Kar Kraft.
TA rules changed each year - The original SCCA GCRs (General Competition Rules) can be found on line for the TransAm series - forgot I had them printed out the scans as a PDF. Flares can be traced directly to horsepower increases needing bigger tire packages. By 73 they were allowing large fiberglass flares but still unibody (full fiberglass fenders, 1/4s, hood and cages from front to rear - more about chassis stiffening than driver protection). When the silhouette cars (full tube) were first built 1980 the only steel part required was the roof panel. In 89 those chassis got full fiberglass sorta looks like a Mustang bodies. Today TransAm is a spec series with 2 levels dictated by sealed engine power levels.
Attached are the 67 & 68 FIA Group II specs for the Mustang.
The primary purpose of Group 2 was to serve as an intermediate class, bridging the gap between Group 1's strictly standard touring cars and the specialized Group 3 GT cars by permitting controlled modifications that enhanced racing capability without departing significantly from road-legal production specifications.[8] This approach maintained a strong connection to everyday road car heritage, encouraging manufacturers to develop affordable, competitive variants that could be raced with minimal deviation from factory builds. By emphasizing close-to-production standards, Group 2 promoted broader manufacturer participation in motorsport, making it accessible for series like touring car championships while ensuring vehicles retained their production lineage
Thank you for providing to those of us "behind the fences" a glimpse into period racing (through your attachments).
Quote from: 98SVT - was 06GT on December 05, 2025, 10:14:08 PMGroup II was a class spec dictated by the FIA. SCCA used those specs to determine the legality of cars competing in their classes. Shelby was allowed by Ford to build their own TA cars in 1967. They were required to use the specs from Kar Kraft to build their cars. In 68 & 69 Shelby ran cars on loan from Ford and built by Kar Kraft.
TA rules changed each year - The original SCCA GCRs (General Competition Rules) can be found on line for the TransAm series - forgot I had them printed out the scans as a PDF. Flares can be traced directly to horsepower increases needing bigger tire packages. By 73 they were allowing large fiberglass flares but still unibody (full fiberglass fenders, 1/4s, hood and cages from front to rear - more about chassis stiffening than driver protection). When the silhouette cars (full tube) were first built 1980 the only steel part required was the roof panel. In 89 those chassis got full fiberglass sorta looks like a Mustang bodies. Today TransAm is a spec series with 2 levels dictated by sealed engine power levels.
Attached are the 67 & 68 FIA Group II specs for the Mustang.
The primary purpose of Group 2 was to serve as an intermediate class, bridging the gap between Group 1's strictly standard touring cars and the specialized Group 3 GT cars by permitting controlled modifications that enhanced racing capability without departing significantly from road-legal production specifications.[8] This approach maintained a strong connection to everyday road car heritage, encouraging manufacturers to develop affordable, competitive variants that could be raced with minimal deviation from factory builds. By emphasizing close-to-production standards, Group 2 promoted broader manufacturer participation in motorsport, making it accessible for series like touring car championships while ensuring vehicles retained their production lineage
Great insight, thanks for sharing!