BMW M328

BMW M328 engine
Overview
Production	1936-1940
Layout
Configuration	Straight-6
Displacement	2.0 L (1,971 cc)
Cylinder bore	66 mm (2.60 in)
Piston stroke	96 mm (3.78 in)
Cylinder block material	Aluminium
Cylinder head material	Aluminium
Valvetrain	OHV
Combustion
Fuel type	Petrol
Chronology
Predecessor	BMW M78
Successor	BMW M335

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.

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 66 mm (2.60 in) and a stroke of 96 mm (3.78 in), the displacement was 1,971 cc (120.3 cu in), 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 59 kW (79 bhp) at 5000 rpm.

Version	Displacement	Power	Torque	Years
M328	1,971 cc (120.3 cu in)	59 kW (79 bhp) @ 5000 rpm	126 N⋅m (93 lb⋅ft) @ 4000 rpm	1936-1940

Applications:

• 1936-1940 328
• 1937-1940 327/28
• 1947-1950 HH

• BMW
• List of BMW engines

• De Ste. Croix, Philip; Noakes, Andrew (September 2010). The Ultimate History of BMW (Hardcover). United Kingdom: Parragon Book Service Limited. ISBN 9781407549781.
• Gillies, Mark; Sedgwick, Michael (October 28, 2010). A-Z of Cars, 1945-1970 (Paperback). United Kingdom: Herridge & Sons Limited. ISBN 9781906133269.
• Hudock, Greg (October 14, 2012). BMW 3 Series – E36 Restoration Tips & Techniques (ebook). United Kingdom: Brooklands Books. ISBN 9781855209701.
• Lewin, Tony (December 25, 2004). The Complete Book of BMW. N.p.: MotorBooks International. pp. 191, 192, 251, 253, 257. ISBN 9781610592055.
• Lewin, Tony; Purves, Tom (2016). The BMW Century: The Ultimate Performance Machines (Hardcover). Motorbooks Press. ISBN 9780760350171.
• Norbye, Jan P. (1984). BMW, Bavaria’s Driving Machines (Hardcover). Skokie, Illinois, United States: Random House Value Publishing, Publications International. ISBN 9780517424643.