M153

The W 153 was the modern Typ 230, built alongside the older W 143 from 1938 and shown publicly at the Berlin motor show early in 1939: an X-braced oval-tube frame in place of the pressed-steel subframe, under a body developed by Hans Gustav Röhr, who had run passenger-car development for two years and died in August 1937 before it appeared. Its engine was the outgoing six with detail changes forced by fuel policy. Compression was lowered so it would run on 74-octane petrol; the combustion chambers were reworked and the bore widened to recover the loss.

Power was accordingly unchanged, at a claimed 116 km/h — the point of the exercise had been to lose nothing. The inlet manifold now heated itself automatically through a bimetallic element. A higher-compression version went into the 230 S competition two-seaters of 1939, of which 21 were built: nineteen roadsters and two fastback sports saloons, bodied in magnesium alloy for off-road events. Then the war closed in. More than half of the 4,262 W 153s date from 1939, and just 87 emerged in 1942 and 1943 together; the bodyshell outlived the car, returning post-war on the 170 S.