Auto Union types C and D
Racing cars made between 1933 and 1939 in Auto Union’s Horch factory, in the German town of Zwickau, were probably the most successful ones in the early years of racing. In those hard times, before WW2, Auto Union had fierce competition with Mercedes and their cars known as ’Silver Arrows’, as the cars of the two German teams dominated Grand Prix racing. Auto Union made racing cars types from A to D, but this time, we will turn our focus to the types C and D.
Auot Union cars were quick, but hard to drive
Auto Union racing cars were based on the 1923 Benz Tropfenwagen and Porsche’s experimental P-Wagen. At the time, due to the unusual mid-engined configuration, there was stiffness of the contemporary ladder chassis and suspension. The car’s turning angle changed as the momentum of the centrally-mounted engine increased on the chassis, causing an oversteer. All Auto Unions had an independent suspension, with parallel trailing arms and torsion bars at the front. At the rear, Porsche tried to counter the tendency to oversteer by using an advanced (for the time) swing axle suspension on the early cars. This undoubtedly was a car which was very difficult to drive.
Video : Grand Prix´s of 1937 – The battle of Mercedes and Auto Union
Trying to overpower Mercedes’ bigger budget
Type C had 16 cylinder six-litre engines with almost 550 horsepower that produced a fascinating maximum speed of 380 km/h. During 1936, the team’s most successful season, they won 6 of 12 Grand Prixs, bringing the Drivers’ championship title to Auto Union, won by Bernd Rosemeyer. Other big names of that time for Auto Union were Hans Stuck, Achille Varzi, Rudolf Hasse and Ernst von Delius.
Mercedes had a much bigger budget than Auto Union, and for the next year it developed the new W125 model, while Auto Union kept the almost unchanged C-type. Regardless, they did surprisingly well, winning five Grands Prix competitions, compared to Mercedes’ seven victories.
Tragic times of Type D
Type D, used in 1938, when the racing legend Tazio Nuvolari had already joined the team, wasn’t as successful. The new model, made to meet the revised regulations, had a 12 cylinder 3-liter engine with a compressor and a 4.5-liter without it. The primary change, except for the engine, was the replacement of the swing axles with a De Dion rear suspension. However, it retained the 750 kg limit of its predecessor.
That year was tragic for Auto Union as Rosemeyer died during an attempt to set a new land speed record, and some memebers of the board wanted to shut down the racing team. Hans Stuck was fired, but soon re-signed. Auto Union type D won only two races in 1938, and two more in 1939.