In 1950, a new DOHC (MT4-2AD) raised power to a maximum of at 6,300 rpm, and in 1953 the engine was enlarged to 1,453 cc, producing at 6,200 rpm. The all new tipo 372 DS twin spark engine with 1,491 cc, which produced at 6,300 rpm, was later used in the O.S.C.A. MT4 TN (for "Tipo Nuovo", "new model") of 1955. With this new engine, the car received the new name FS 372, of which five were built. One of these belongs to Sir Stirling Moss, who raced it in historic races across the globe until his retirement in 2011. Versions of this engine went on to be used in coupé and convertible models of regular Fiats from 1959 to 1966.