Group 2 wheels and tires

[highland green]

legendary motorcars has a 1967 TA for sale on their site. #24 of 26 produced. Fred Southerlands car. some great close up photos.

[68blk500c]

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

Thank you for providing to those of us "behind the fences" a glimpse into period racing (through your attachments).

[FL SAAC]

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

Great insight, thanks for sharing!