The Mercedes-Benz M08 engine is a naturally-aspirated and supercharged, 4.6-liter and 5.0-liter, straight-8 engine, designed, developed and produced by Mercedes-Benz; between 1928 and 1940.
The engine was a 4,622cc straight-8 side-valve unit for which maximum output was given as at 3,400 rpm
For 1929, the company's first eight-cylinder model was extensively reworked by the newly appointed Technical Director Hans Nibel. The 8-cylinder engine and most other technical details were carried over unchanged from the 1928 car including the ratios chosen for the four-speed manual transmission.
In 1931, the car became available with an enlarged 4,918cc engine which now also featured a twin downdraft carburettor. Maximum output was now listed as at 3,100 rpm and claimed top speed increased to 110 km/h (69 mph).
In 1932 the W08 lost the âÂÂNürburgâ name, being sold simply as the Mercedes-Benz Typ 500. The 4,918cc side-valve engine with its twin downdraft carburetor was unchanged, as were the four-speed optional overdrive transmission, wheelbase, and list of standard body types.
1936 saw an increase in claimed maximum output from the engine to at 3,300 rpm. The cylinder capacity at 4,918cc was unchanged, but there was a marginal raising of the compression ratio. The claimed top speed was now raised further to 123 km/h (76 mph). The model was discontinued in 1939 without any immediate successor. Twenty-four years passed before the next 8-cylinder engined Mercedes-Benz appeared; with the Mercedes-Benz 600, in 1963.