The SA22C / FB RX-7 had a long motorsport career. In 1980 Mazda began developing it for Group 5 regulations. Initially the bodywork was developed, this was tested over an existing racing chassis before an injected 13B was fitted. Testing included comparison with the existing 12A IMSA spec car. Photos from these early tests are shown here. It's hard to see, but it looks like the cars were fitted with SSR Mk2s wheels. The RX-7 would continue to its peak in 1982 with the Group 5 254i achieving 14th place at Le Mans, before the Group C 717C was introduced in 1983
