An auto union, a group of auto makers led by Audi, created the D-Type racer that dominated the European Grand Prix racing circuit during its short lifespan. The D-Type was introduced in the middle of the 1938 season, and was dominating the Grand Prix circuit when World War II broke out and ended the year early.
The car reached speeds of 200 miles per hour or more and was an immediate success. In 1938 the car placed third in the German Grand Prix in its very first race. Other D-Type cars won the Italian Grand Prix and the Donnington Grand Prix in England before the year ended.
In 1939 Hermann Muller won the French Grand Prix, was second at the German Grand Prix and fourth at the Swiss Grand Prix. He also registered wins at Grand Prix races in Yugoslavia and Rumania. Two days after the Yugoslavia race, Germany invaded Poland, starting WWII. That ended the season and since Muller was leading in the standings at the time, he became the unofficial champion.
The car was one of the first to have the gas tank and engine behind the driver. It had a 3.0 liter engine in a V-12 formation. It was originally designed to be a V-16, but restrictions were put in place forcing the company to settle for 12 cylinders. Still, the super charged engine produced 550 horsepower.
Before the 1938 season Grand Prix cars had engines as big as 6 liters, and the racing establishment lowered the size to start the season. That led to the development of the D-Type.
As a V-12, it has two cylinder blocks set at an angle of 45 degrees, with a single overhead camshaft that operated all 32 valves. The car also went through a lot of testing in the wind tunnel of the German Institute for Aerodynamics.
The top automotive engineers in Germany worked to develop the racing car. They were also helped by the government, as Hitler approved giving them and their chief rival Porsche heavy governmental sponsorships to develop the best racing cars possible.