Mercedes-Benz M100 engine

The Mercedes-Benz M100 was a single overhead camshaft V8 petrol engine built by Mercedes-Benz from 1964 to 1981, first as a 6.3 litre unit and from 1975 as an enlarged 6.8 litre unit. It was introduced in the flagship Mercedes-Benz 600, succeeding the 3.0 litre straight-six M186 line, and it was later fitted to the S-Class based 300 SEL 6.3 and, in its larger form, to the 450 SEL 6.9. It had a cast iron block, aluminium alloy heads and sodium-filled valves, and the early engines used Bosch eight-point mechanical fuel injection, which the 6.9 replaced with K-Jetronic. The 6.9 also used a dry sump system carrying twelve litres of oil, which let the engine sit lower under the flatter bonnet of the W 116 body.