In 1932 FIAT began the development of a new series of "high-speed", four-stroke Diesel engines with direct injection, characterized by a 60° V-shaped arrangement of cylinders with a bore of 160 mm, a stroke of 180 mm, in a crankcase made with welded steel components. These engines were produced in large numbers in two versions with 12 cylinders (V 1612) and 16 cylinders (V 1616). Thanks to their mass-to-power ratio, engines of both types were used in the naval sector, for various fast boats of the Regia Marina, including MAS (with the 16-cylinder version), patrol boats and minesweepers, as well as in the railway sector. The ATR.100, a 3-body articulated railcars, were equipped with two V1612 engines allowing a maximum speed of over 160 km/h and maintaining a cruising speed limited to 120 km/h for safety reasons. From 1935 to 1961, the ATR.100s remained in active service, maintaining the same type of engines in the various modernisations. After World War II, the V 1612s were also to repower 12 FS Ne 120 heavy shunting locomotives, ex Whitcomb 65DE14, originally equipped with diesel engines produced by the US Buda Engine Company. The engine on display is a railway type V 1612 and its crankshaft is shown separately for educational purposes, together with connecting rods and pistons.