The BMW M328 is an overhead valve straight-six petrol internal combustion engine which was produced from 1936 to 1940. It was a high-performance development of the BMW M78 engine that was produced alongside the M78. Compared with the M78, the M328 has an aluminium cross-flow cylinder head with hemispherical combustion chambers. The M328 was used in the BMW 328 and BMW 327/28 coupes. After World War II the engine was also licensed to Bristol Cars in the United Kingdom. Design The M328 had an unusual valvetrain design; although the camshaft is located in the engine block, the exhaust valves are actuated by a transverse pushrod from the intake valves. This results in a valve layout similar to a DOHC engine. With a bore of and a stroke of , the displacement was , the same as its M78 predecessor. Fuel supply was via three Solex "30 JF downdraft" carburetors. The M328 engine has a compression ratio of 7.5:1 and produces at 5000 rpm. Versions Applications: 1936-1940 328 1937-1940 327/28 See also BMW List of BMW engines References Notes Bibliography M328 Straight-six engines Gasoline engines by model