Mercedes-Benz M11 engine

The Mercedes-Benz M11 was a naturally aspirated 2.6 litre straight-six piston engine designed and built by Mercedes-Benz between 1929 and 1935. It was a side-valve unit of 2,581 cc that delivered 50 PS at 3,400 rpm, which in the car that carried it translated into a top speed of about 90 km/h. The engine powered the W11 passenger car, which was sold under several names, including the 10/50 PS, the Typ Stuttgart and the Typ 260. Its naming followed the German convention of the period, in which the first figure gave the tax horsepower, a rating derived from cylinder bore and stroke and used to set the annual car tax, and the second figure gave the manufacturer claimed output in metric horsepower. Power reached the rear wheels through a four-speed manual gearbox whose fourth gear acted as an overdrive.