The Canadian-American Challenge Cup was co-sanctioned by the SCCA and CASC; it was nicknamed the “unlimited” series. Although there was a basic set of rules, the cars had to be two-seaters with bodywork covering the wheels, have doors, a windscreen, brake lights and various safety requirements, otherwise there was no regulation on the cars dimensions, minimum weight, materials used or size of the tires. This was all open to the creativity of the designer. The term “unlimited” came from the…

Photo: Chuck Andersen