A Chrysler internal Bulletin, 11B, dated March 5, 1970, was the very beginning of the Challenger Tran Am. It was a limited production model, manufactured to comply with the Sport Car Club of America homoglation rules.

Sam Posey battled Camaros and Mustangs in races across America in 1970. Chrysler delivered a body-in-white (essentially a bare unibody) and a second Challenger for parts, to his shop for the basis of his road-racing machine. Ray Caldwell and Carroll Smith were the team management for the #77 T/A, and the LA-engine based monster was built by none other than Keith Black.

At that same time, the boys at Dodge Main were up to their own R&D as well. A 340 Challenger, wearing a dual snorkel-hood and a bumble-bee stripe (and possibly painted Plum Crazy with dog-dish hubcaps) became the engineering mule for the later JH23J cars.

When the Hamtramck plant started producing the A53 Trans Am models, March 10, 1970, they were producing a very unique machine. These models all recieved the special 340 six barrel. It had a beefier valve train, revised bottom end, and an Edelbrock manifold topped with a trio of dual-throat Holleys.

The Challengers all had a special fiberglass hood (that had different springs than other steel-hooded cars did), Hemi front fenders (different wheel lip radiuses), special spoilers, a quick-ratio steering box, side exit exhaust (even the California cars had these) increased camber in the rear springs, E60x15 tires in the front, and G60x15 tires in the rear. The Trans Am, and its AAR cousin, were the first production cars to have two different size tires. Ever. The T/A only had the Rallye or black steel dog-dish hubcaps for wheels. There has been some confusion as to the type of trim rings that came with the Trans Am, some varieties had polished trim rings, with red stripe aluminum caps, while others had the brushed stainless beauty rings.

The radio antenna was moved to passenger's rear quarter, it was believed that the fiberglass hood would interfere with the antenna's reception capability.

The Challenger T/A models were fairly similar in production, but unique rarities do exist, option code V02, which is two-tone paint, were present in two examples. Another rarity, is the T/A that came with a sunroof. Only one example is known to exist, thanks to Chrysler shipping records.

The exact number of Trans Am cars isn't known, but the accepted number is close to 2400, with an additional 118 sent to Canada, (75 automatic, 43 manual) with 0 known exported to other countries (1 T/A is known to currently be in Kenya).