Lord K's Garage #151: Silver Fish

Back to the racetrack! Meet one of the most unusual and highly successful Diesel Era racing cars - the Auto Union Type A.

Four months ago, we heard the story of its mighty rival, the Mercedes-Benz W25 dubbed 'The Silver Arrow'. Today, the Garage is happy to present 'The Silver Fish'.

In 1932 German manufacturers Audi, DKW, Horch and Wanderer joined forces to form Auto Union*. The main goal of this joint venture was to get a better position in the market and offer some real resistance to Mercedes-Benz. Although all four continued to produce cars under their own name, they shared technology and a four-ring badge on the radiator. When Mercedes-Benz announced their intent to enter Grand Prix racing in 1934, Auto Union could of course not stay behind, especially considering the huge support offered by the German government. With no real racing experience at hand this was easier said than done. They eventually employed the services of Dr. Ing. h. c. Ferdinand Porsche and Adolf Rosenberger, who were already in the process of building a new Grand Prix car (the so-called P-Wagen).

Porsche had previously been employed by Austro Daimler and Mercedes-Benz for whom he designed the highly successful S-Type racing car. Earlier, in 1923, he co-designed (and Rosenberger piloted) the Benz Tropfenwagen (Teardrop Car), seen here as a pure racer (above) and in its 'street-legal' guise (below).

Almost a decade earlier Rosenberger had successfully raced a mid-engined car and he convinced Porsche to follow that route for their new Grand Prix racer. They felt there were several major benefits of this layout. Firstly there would be considerably more weight on the rear axle, which should improve traction. Another advantage was that a prop-shaft running through the driver's compartment was no longer required. This meant that the driver could sit considerably lower in the car, lowering the centre of gravity and also the wind resistance.

The location of the engine was just the first of many unconventional design elements of the Porsche/Auto Union Grand Prix car. Even though Porsche was restricted to a maximum weight of 750 kg, he opted for a sixteen cylinder engine, keeping the mass down by using exotic alloys for the block and head.

The cylinders were angled at 45 degrees, leaving just enough space for the intake manifold, which fed from the rear of the engine by a huge Rootes-Type Supercharger. Porsche opted for a simple and lightweight valvetrain consisting of a central camshaft, operating the valves to push-rods and rockers. In its first version, displacing just under 4.4 litres, the V16 engine produced 295 bhp at just 4500 rpm.

Completed by a five speed gearbox, the drivetrain was installed in an unusually conventional tubular ladder frame with four cross-members. The front cross-member carried the independent suspension, which was by two trailing links. The bottom ones were connected to each other with a torsion bar running through the cross-member. The top links sported friction dampers. The rear suspension was independent as well with swing axles and one radius arm on each side to control the braking and acceleration forces. There was a single transverse leaf spring and a friction damper for each side. Lockheed hydraulic drum brakes were fitted all around.

Dubbed the Auto Union Type A, the revolutionary mid-engined Grand Prix car made a very high profile debut at Avus in May of 1934. The new Mercedes-Benz cars were also present, but a problem discovered in practice forced them to withdraw. Auto Union driver Hans Stuck took the lead during the very wet first lap and had built up a one minute lead after just one lap. Behind him two Alfas fought for second and eventually for the lead when Stuck was forced to retire with a clutch failure. August Momberger was the only surviving Auto Union driver and he crossed the line in third, which was quite a disappointment after Stuck's superb first lap, but there clearly was plenty of potential in the Auto Union GP car.

In the next few races, Auto Union's debut performance was put in perspective by the now fully functioning Mercedes-Benz W25s and the all-star driving team. Only Stuck could match them and scored Auto Union's first major victory at the all important German Grand Prix at the Nürburgring. The unusual layout of the Auto Union suited hillclimbs particularly well and Stuck won four of them in 1934.

The Type A served as a platform for a pair of even more unusual record cars. Before you see them, it's important to understand that 'Lucca' and 'Avus' were a Type A development. When you come across an article or a caption elsewhere, erroneously presenting these vehicles as a Type B (or even C, though the latter is a result of confusion between the racing category, i.e. Class C, and the car type) derivatives, don't you believe it.

The Auto Union team went to Gyon for record attempts but the circumstances were bad with snow so after two test runs the team went to Italy instead. After having dismissed the Milan - Varese road they finally made the record runs at Florence. On the return run of his 3rd attempt Stuck set a time of 11.01 on the kilometer in his 'Lucca' enclosed car, making him the first driver to run over 200 mph on a road but it was not accompanied by any good run in the other direction so Stuck failed to take Caracciola's record. But a combination of the 3rd and 4th runs gave Stuck the 1 Mile record which also was the fastest record made on a road - 320.267 km/h (199.005 mph).**

To avoid further confusion, just click on the picture above and read a short article by Roger Taylor, delivering the true story of these amazing machines.

A line drawing (also by Roger Taylor) will help you tell the difference between the two streamliners. And for a dessert, two nice shots of the Tripoli/Avus Auto Union:

* Article: Wouter Melissen, Ultimatecarpage.com with minor additions by LK

** Source: Speed Record Attempts

Headline picture: Ferdinand Porsche, Hans Stuck and the Type A at the Masaryk Grand Prix, Brno, Czechoslovakia. 1934