It was with his own HWM cars that Abecassis raced in his only two Formula One World Championship Grands Prix, at the Bremgarten circuit, in the 1951 and 1952 Swiss Grand Prix. He was more successful as a sports car driver with Aston Martin and won his class at the 24 Hours of Le Mans in , sharing his DB2 with Macklin. He also finished second in the 12 Hours of Sebring in 1953, partnered by Reg Parnell. In 1953, Abecassis constructed an HWM sports car for his own personal use, powered by a Jaguar straight-6 engine, with which he successfully contested many national British races until 1956.