Issigonis‘ friend John Cooper, owner of the Cooper Car Company and designer and builder of Formula One and rally cars, saw the potential of the Mini for competition. Issigonis was initially reluctant to see the Mini in the role of a performance car, but after John Cooper appealed to BMC management, the two men collaborated to create the Mini Cooper, a nimble, economical and inexpensive car. The Austin Mini Cooper and Morris Mini Cooper debuted in 1961.
The original 848 cc engine from the Morris Mini-Minor was increased to 997 cc, boosting power from 34 bhp to 55 bhp (25 to 41 kW).The car featured a racing-tuned engine, twin SU carburettors, a closer-ratio gearbox and front disc brakes, uncommon at the time in a small car. One thousand units of this version were commissioned by management, intended for and designed to meet the homologation rules of Group 2 rally racing. The 997 cc engine was replaced by a shorter stroke 998 cc unit in 1964.