Lighter and more powerful, the 100S developed for racing and enjoyed success around the world. Not long after the Austin-Healey 100 went into production, Donald Healey started the process of creating a version to go racing. Five test cars were produced during this time that went on to participate in races and land-speed record attempts. By 1955 the 100S was ready.
Built around a steel boxed-section frame with X-brace, double wishbones with coil springs, a live axle and semi-elliptic leaf springs. The straight four engine had a revised alloy head with higher compression and better breathing SU carburettors. Power rose by 40 hp to a new high of 132 hp with 168 lb-ft of peak torque.
