The Canadian-American Challenge Cup was a series nicknamed the “unlimited” series co-sanctioned by the Sports Car Club of America and the Canadian Automobile Sport Clubs. 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—there were no regulations specifying the car’s dimensions, minimum weight, materials used, or size of the tires. This was all left open to the creativity of the designer.
The nickname “unlimited” came from the regulations allowing engines of unlimited displacement and number of cylinders, that is, unlimited horsepower. Essentially, this was the open sports racing car series, and it became a hotbed of new technology and racing car design.
No Subscription? You’re missing out
Get immediate ad-free access to all our premium content.
Get Started
