 Auto Union Typ D
These were two difficult years 1938 and 1939 for the racing department of Auto Union. Bernd Rosemeyer suffered a fatal accident at his record attempt in late January. The contract with Ferdinand Porsche had ended
already. In his place, a team led by Robert Eberan-Eberhorst developed the cars further.
The time of the cars with the big engines has gone. The regulations now prescribes up to 3 liters displacement and 750 kg weight. Compared to the predecessor the car chassis is similar, the engine has thoroughly
changed. The arrangement of the carburettors before charging has been maintained.
It has 'only' 12 cylinders, thereby another cylinder angle and a completely different engine control, each cylinder bank with a camshaft above and a third one in the middle. This is directly driven by the vertical shaft. At the same
time the vertical shaft drives two horizontal intermediate shafts being connected to the other camshafts.
1938 only one compressor drives the engine to 309 kW (420 hp) with a maximum of 1 bar. 1939, there are two of them working in two stages. The result is a greatly increased power output per liter. The achievable speed is
not far from that of its predecessor.
Nevertheless, the remaining drivers like Nuvolari, Stuck, Müller and Hasse can no longer meet the successes of 1936. Below you can see the for the saison of 1940 provided GP car with 1.5-liter displacement. Due to the
start of World War II in September 1939, it is never used.
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