It's one thing to listen to stories about monster pre-war Grand Prix cars, but the sight and sound of one up close and personal has to be experienced to be believed. In 1936, the great Hans Stuck came to the beautiful Worcestershire countryside, tearing apart the peace and tranquillity by driving his V16, 520hp
Auto Union Type C
Grand Prix car up the Shelsley Walsh hillclimb.
One way to draw the crowds!
The thought of driving a modern Formula 1 or LMP1 car up the narrow 914.4-metre long (1,000-yard) track today seems ridiculous. But consider the 211mph Type C runs on skinny vintage tyres and the prospect is, quite frankly, terrifying. And by the way, despite the wet weather Stuck still managed to record a time of 45.2 seconds.
Eight decades later, a Type C returned to Shelsley Walsh. Audi had the great man's son, Hans-Joachim Stuck, drive a perfect replica of his dad's car at the Classic Nostalgia days last weekend (July 16/17). If Stuck Senior was one of the greatest drivers of his generation, Stuck Junior has an impressive record too. IMSA race winner, 1990 DTM champion, accomplished Formula 1 driver and winner of Le Mans twice in a Porsche 962 C, Stuck has a formidable reputation on track, but admitted that he saw this as a particularly significant challenge.
"How crazy must my dad have been to drive this thing up the hill that fast? It's incredible and with no grip at all," Stuck told us after his first run. "It's completely different to any modern car. The gearbox is fantastic but the steering is a bit lazy. The throttle response is fabulous; you know how much torque this thing has? 627lb ft at 2,500rpm. It's amazing, I can never go full throttle anywhere without wheelspin." So that begs the question - what do you do when it's wet then? Stuck laughs. "Go drifting." The oversteer can be difficult to catch though: "You don't feel it at first because you are sitting so far in front of the centre point."
Wheelspinning everywhere, even with these
"Everything is heavy," he continues, "you wonder how those guys could have done an entire Grand Prix. Where did they get the strength from for steering and shifting for that long?" Stuck hasn't taken the Type C to its maximum speed but he has driven it at 140mph and reports that "the buffeting is not too bad actually, the small screen is surprisingly effective." Despite only having twin-leading shoe drum brakes the stopping power is pretty good too. "I don't expect them to stop like carbon fibre brakes, but they do stop well."
Although the Type C definitely looks like something from a long, long time ago, there's nothing antiquated about the engine technology. The 32-valve V16 configuration was chosen because Auto Union wanted to use the maximum capacity in the class. 16 cylinders gave what the designers considered the optimum bore and stroke of 75mm x 85mm and a final capacity of 6,010cc. On the rear of the engine is a Rootes-type supercharger fed by a carburettor. Originally maximum boost was 0.95bar, although the man in charge of Audi's vast fleet of heritage vehicles at Audi Tradition, Timo Witt, says they run slightly less boost, around 0.8bar. "In those days, they had a huge team of engineers rebuilding engines after every race but we need the engine to last," he said.
The replica is precise, using an original car as a pattern but with a few technical changes made for practical reasons and because of the availability of superior quality materials and components. One example is the crankshaft, which was originally made by Hirth and ran in roller bearings. This one runs in plain bearings like any modern engine. Neither the original nor the replica needs a flywheel because there are 16 cylinders and the throttle response is instantaneous. The car's engineers are able to run the engine from cold on a single set of plugs (where once they would have used a different heat range for starting). Because there are so many cylinders, they can't tell whether they are all running sweetly by sound alone. To do that they use a pyrometer (a high-temperature digital thermometer) to check the temperature of each exhaust stub. If one is cooler than the others, it means it is off-song.
Stuck was also reunited with another old friend that day, the Audi IMSA S4 GTO. This car is chassis 001 and was evolved from the Audi 90 IMSA GTO which was dismantled and built into the 'C4' S4 body. Stuck drove the car at its debut meeting, the penultimate round of the 1992 Westbank Modified Series at Killarney, and won both races. At the end of that year it switched to Rothmans livery from the original Audi red and silver, in which it now appears.
Another five-cylinder Audi hero!
It was acquired from the USA by John Hanlon (who owns several other special Audis, including an S1) just a couple of weeks before the event. With 720hp and 531lb ft from the now legendary 2,192cc, five-cylinder engine and quattro four-wheel drive, it whistled, chattered and howled its way up the hill. Both cars underlined the difference 56 years can make in racing car evolution and Stuck told us afterwards: "I drove the sister car at an event in Germany two weeks ago. Fantastic gearbox, good power and brakes, all-wheel drive; it brings back happy memories." These two cars just created a few new memories for us as well.
Watch the Audi IMSA S4 GTO
here
Watch the Auto Union Type C
here