In October 1932, the AISCR (later to become the FIA) announced specifications for a new racing class. It was incredibly simple. A weight limit of 750 Kilos (1653 lbs) without oil, water, and tires. That was about it. Any engine size, super-charged or not, any configuration, any shape. This wide latitude sent the minds of designers and engineers into hyperactive mode. A newly independent Ferdinand Porsche, along with partners Karl Rabe and Adolfo Rosenberger, decided to build a car to these specifications despite not having a customer. A bold move given the depression era environment.
Hans Stuck with the enclosed record-breaking versionPorsche and the team decided on a 45 degree V-16 mounted in a mid-engined configuration with independent suspension at all four corners. With the weight restriction, the engine displacement ended up being 4.3 liters. Getting 16 cylinders into a 4.3 Litre space and then getting high output was the work of Karl Rabe. The machine had a redline of 4500 rpm and produced 295 hp. The team also worked on a 3 seater sports car based on a detuned version of the same engine. However, it was never produced. The body of the racing car utilized the teardrop shape and later included innovative aerodynamic wheel fenders, and a removable coupe top.
Fortunately for Porsche, along came Auto Union which had been newly formed from components including DKW, Audi, and Wanderer. They thought that racing would be a good way to advertise and showcase the strength of the new company. They approached Dr Porsche, and yes, he happened to have a racing design they might be interested in. The design was transferred to Auto Union, and the car was initially called the Auto-Union-P to honor the designer. Porsche had simply called it Design #22. Auto Union approached the German government and convinced them to split incentive money and a stipend previously offered only to Mercedes. This set up the famous battles between the two auto makers, and the term Silver Arrows which applied to the cars from both. In March 1933, Hans Stuck set a new hour record with the Auto Union car at 134.9 mph. Despite the car being notoriously difficult to drive, Stuck went on to win the 1934 Grand Prix of Germany, the Grand Prix of Switzerland, and set several more world records. The slightly modified version of the car with enclosed rear fenders and top ran over 200mph in record attempts. The following year, he won at Monza and Tunisia, among other victories.
The car was a resounding success. Increases in output and evolutions of the chassis lead to more success in subsequent years, and of course there were the classic battles with the Mercedes, and the Alfa Romeos. Eventually, at the end of the 1930s, the war brought everything to a halt, but the legendary status of Design #22 was already established.