Initially, 848 cc engines were included in the Mini Cooper S and a 997 Cubic Centimeter engine was included later for increasing the power to55 bhp from a mere 34 bhp. The car featured a racing tuned engine, a closer-ratio gearbox, twin SU carburetors, and front disc brakes, which was quite uncommon.
John Cooper, owner of the Cooper Car Company and designer and builder of the Formula One had already seen the potential of the Mini for competition. His friend Issigonis was however not convinced. John Cooper appealed to the BMC management, convinced them.