Auto Union Takes on the Grand Prix
Work on the first ever Auto Union Grand Prix car began on March 7, 1933. Exactly one year later, in March 1934, driver Hans Stuck would use the car to set a new world speed record on the Avus Ring in Berlin. And that was just the start of the cars that, because of their speed, styling and colour, would come to be known as the Silver Arrows.
In 1933, the Auto Union was just one year old, but already determined to challenge Mercedes on the Grand Prix circuit. Lacking the expertise in racing-car design to do this on their own, they turned to a figure whose name would become legendary in sports and racing car circles - Dr. Ferdinand Porsche.
Porsche had had success working on racing cars for Austro-Daimler and Mercedes, but, together with racer Adolf Rosenberger, he came up with something groundbreaking for the new Auto Union racing car - a mid engine.
Now, some eighty-odd years later, the mid-engined layout has been universally accepted in motor sport and to return to a front-engine would be as unthinkable as Porsche and Rosenberger's idea must have seemed in 1933. But Rosenberger had some experience with the layout, having previously piloted the concept several years earlier, and he and Porsche believed (correctly) that the setup offered huge benefits. For one thing, it would give the car better traction as there would be more weight over the rear axle. In addition, there would be no driveshaft running through the cabin, so the driver could be seated lower down in the car, which would reduce the centre of gravity and allow for more aerodynamic bodywork.
Porsche's innovations didn't stop at re-locating the engine, either. Racing rules limited the car to a maximum weight of 750 kg, but in spite of this, he opted for a sixteen-cylinder powerplant in a V-formation, and kept the weight down by casting the engine block and cylinder head in alloy. The intake manifold was squeezed in between the 45-degree cylinders, while a massive Rootes-type supercharger fed this from the back of the engine.
Both front and rear suspension were independent. The front suspension was mounted on the leading crossmember of the car's ladder frame, while the rear featured swing-axles and radius arms, with a single transverse leaf spring. Stopping the car was achieved through Lockheed hydraulic drum brakes, while the flexible engine meant that the car only needed a four-speed gearbox.
The first of these fearsome machines was named the Auto Union Type A and its first major track victory would come, fittingly enough, in the German Grand Prix of 1934 with Stuck at the wheel. The Type A produced 295 hp, but work continued on the car and for 1935, the Type B would up this to 375 hp and add torsion bar rear springs which improved the car's handling, even though the tyre technology of the day could barely keep up with the Auto Union's technology.
An Auto Union Type C in its element on the racetrack
1936 saw the Type C debut, for which Porsche outdid himself, increasing the engine's displacement to over six litres, giving 530 hp. In this form, Stuck and the hugely-talented young driver Bernd Rosemeyer, campaigned the car with excellent results, making it Germany's most successful car of the 1936 season. With Porsche occupied on what would eventually become the VW Beetle, few changes were made to the Type C for 1937, and in 1938, development of the V12-powered Type D began.
Races and Records
In the 1934-1939 period, a total of 61 circuit races were entered by Auto Union, including 30 Grands Prix. A total of 24 races were won, with 23 second places and 17 third. In addition to circuit racing, however, other versions of the Auto Union were highly successful at hillclimbing, road racing and record breaking - during the same period, the car won 18 out of 23 hillclimbs. Stuck was German hillclimb champion in 1934, 1935 and 1938, while Rosemeyer won the title in 1936 - the same year he won the Eifelrennen, German, Swiss and Italian Grands Prix and came second in the Hungarian Grand Prix, winning himself the title of European Champion, just the second year that the title had existed. Auto Union drivers also won the German road racing championship in 1934, 1936 and 1938.
Rosemeyer seated in one of the Auto Union racers
But being European World Champion was just one of Rosemeyer's achievements. In October 1937, he because the first person to drive at over 400 km/h on an ordinary road, taking a Type B to 404.6 km/h on the Frankfurt to Darmstadt autobahn.
The Model Record Cars
Brumm's 1/43 scale model depicts the Type B used for this feat, with its enclosed rear wheels, in excellent detail, with racing number 4.
The Brumm Type B Record Car
The company has also modelled an Avus racing version of the same car with open rear wheels and racing number 3.
Type B Avus with open rear wheels
The Auto Union racers were fitted with various different bodies for different types of racing - some of the hillclimb cars even boasted double-rear-wheels. But none were as spectacular to look at as the streamliners.
One of the stunning re-created Auto Union Streamliners currently in the Audi collection
When designing the original Type A, Porsche was required to bring it in at under 750kg in order to meet then-current circuit regulations. However, there was one type of race where there was no weight limit, the Avusrennen.
In 1936, Berlin's Grand Prix track, Avus, underwent redevelopment, gaining a new banked north curve, with a banking of 43 degrees making what was already a fast track even faster. With no weight limits placed on cars that raced there, streamlined cars had made regular appearances, and for 1936, Auto Union built and entered two streamliners of their own. Much heavier than the standard cars, their flowing, fully-enclosed bodywork boasted futuristic design features like pop-up canopies covering the cockpits and automatic internal jacking systems.
Reigning European champion Rosemeyer was one of the only drivers who could drive such a monster to its full potential and during practice, he set an unofficial lap record of 4:04.2. Ultimately, after having to stop for tyres, Rosemeyer finished fourth, but his final lap 4:11.2, an average speed of 276.39 km/h - the fastest racing lap of the pre-war era.
The Model Streamliner
The Revell Streamliner
Revell's 1/18 scale model of the 1937 Streamliner has fully captured the car's flowing lines, measuring approximately 30 cm in length. The model features a detailed V16 engine beneath the removable engine cover, as well as an opening canopy, rubber tyres and working steering.
The Revell model's authentically-detailed V16 engine and opening features
The Auto Union Racing Cars Today
Just six of the Auto Union racers remain today. Eighteen of the team cars were found hidden in a colliery outside Zwickau by the Russians in 1945. The cars were shipped back to Moscow and distributed to car manufacturers and engineering institutes there, most getting lost along the way.
However, one complete car has since been found and rescued, and five others have been restored or recreated from recovered parts by British firm Crosthwaite and Gardiner.
To mark the Audi Centenary, and the 75th anniversary of the Silver Arrows, the six cars will come together in November at the Audi mobile museum in Ingolstadt - more Silver Arrows than have ever been together since the 1930's. Entitled Family Silver - the Era of the Silver Arrow Grand Prix Cars, the exhibit will run until the end of February 2010.
All three of the stunning models shown above are now up for auction in our special forum section here, along with all the models from last week. All proceeds go to the Helen & Douglas House, which provides hospice and respite care for children and young adults.
For more information about the range of model cars available from Audi, please visit www.audi.co.uk/merchandise
Next Week: Two strokes to postwar recovery!