M14

The board had killed the W01 because a six-cylinder engine was ruinous in a car that small, and told Ferdinand Porsche to come back with something the company could afford to build. His answer in 1928 was the same 5/25 PS project rebuilt around a side-valve four of 1,280 cc, fed by a single Solex downdraft carburetor and making 25 PS at 3,300 rpm. Knowing the four could not match a six for flexibility, he specified a four-speed gearbox to paper over the gaps. Twenty-eight prototypes were completed as tourers and saloons.

Management liked this one considerably better — and then did the arithmetic. Break-even was set at a thousand cars a month, which meant committing ten million reichsmarks immediately, and in 1928 Daimler-Benz would not. The project was filed away, and not one of the 28 cars was ever given a price. Porsche was gone by the following year, replaced by Hans Nibel. The small Mercedes he had been chasing since 1926 finally reached showrooms in October 1931 as Nibel's Typ 170 — with six cylinders after all.