From the archives with Doug Nye

A season to forget

After a triumphant 1935, Mercedes-Benz dropped the ball – and Auto Union grabbed it

Eighty years ago, as the Grand Prix racing season of 1936 approached its conclusion, it was very apparent that Mercedes-Benz had screwed up. For many observers, even then, such a reality seemed a) barely conceivable yet b) something of a relief to see someone else winning… 

That season’s top-tier racing had been dominated by the upstart new rival Auto Union marque – with its superstar driver Bernd Rosemeyer who would win the European Championship title (the World Championship equivalent of the time). Alfa Romeo was also victorious which left only two early wins to Mercedes whose entries would be scratched from four races when the management realised they could not compete. Better a no-show than a bad show. 

During 1935 Mercedes planned a new 60-degree V12 engine, the 5.57-litre Typ DAB, for 1936 but it proved hopelessly overweight at 650lbs, 250lbs more than the 1934-35 straight-eights. Power output was fine at 570bhp, but its great weight would have made the proposed 1936 V12 car impossibly nose-heavy.

In consequence Albert Heess’s engine-design unit instead expanded the original M25 straight-eight Grand Prix engine to the maximum permitted by its 95mm cylinder-bore spacing, to displace 4470cc as the M25E variant.

Four new Grand Prix cars were built for the coming season. Partly to accommodate a larger and heavier engine this new design’s wheelbase was slashed by more than 10 inches to 97 inches overall. This concept was also intended to increase rearward weight bias, hopefully improving traction as power output had escalated.

This drastic reduction in wheelbase was aided by an entirely new lateral-shaft transaxle. It lowered the car’s prop-shaft by stacking the two transmission shafts laterally beneath the final-drive spur gears instead of having the gearbox section in-line as in 1934-35. Worries that the change in drive direction added another pair of power-absorbing gears evaporated when testing proved the loss acceptably low. 

These ‘Model 1936’ cars also adopted a new de Dion-influenced rear suspension system. The 1934-35 swing-axle system was replaced by a solid ‘dead’ axle connecting the wheels side to side, with separate universally jointed open drive shafts to each hub. The axle was a Y-shaped steel-tube fabrication, the arms of the Y carrying the wheel hubs while the single leg extended to a ball-pivot joint on the chassis’ tapered rear end. This ‘Y’ fabrication initially rode vertically between rubber-faced rollers housed in a guide channel at the back of the transaxle casing. In service that system would be replaced by a steel-faced vertical guide in the back of the transaxle, in which a bronze axle-guide would ride.

Springing was by quarter-elliptic leaf springs, while the parallel-link front suspension with horizontal lateral coil-springs housed in the front chassis cross-member was carried over from 1934-35.

The ‘Model 1936’ was given a lovely almost circular-section body, with front and rear suspensions carefully cowled. One minor early problem was that tall, muscular Manfred von Brauchitsch could hardly fit into the new cockpit…

The new Mercedes-Benz won first time out but with ‘Rainmaster’ Rudi Caracciola driving on the rain-soaked, slow circuit at Monte Carlo. Two V16-cylinder rear-engined Auto Unions finished second and third. Second time out was very different – under the baking Libyan sun on the high-speed Mellaha course at Tripoli, both handling and steering were criticised and high raceday winds gave all drivers queasy moments. Auto Unions finished one-two. The less important Tunis GP then gave Mercedes-Benz its second win of 1936 – once the rival (and leading) Auto Union of Varzi had crashed and Rosemeyer’s had caught fire.

In the Pena Rhin race at Barcelona the ‘Model 1936’ cars were heavily criticised for their abrupt pitch change which unsettled the handling and the drivers. And Tazio Nuvolari won in a V12 Alfa Romeo.

Engine troubles also affected Mercedes-Benz. Rosemeyer’s Auto Union led three Alfas home in the EifelRennen at the Nürburgring. Despite extensive engine development the Model 1936 again failed badly in that year’s German Grand Prix – dominated by Rosemeyer’s Auto Union. Thereupon Daimler-Benz decreed a pause in racing activity. Works-team racing was reorganised, with a sub-division of the Experimental Department introduced, to be entitled the Rennabteilung – racing department. Young engineer Rudolf Uhlenhaut,
just 30, was given responsibility for assembling, preparing and testing the GP cars before delivery to Neubauer’s sporting department to be raced.

From August 10-15, 1936, the new department conducted intensive testing at the Nürburgring. Planned race entries at Livorno and Pescara were cancelled. Caracciola and von Brauchitsch test-drove, reporting “…a marked bouncing of the front wheels from the ground and very substantial juddering of the wheels, clearly more on the new car than the old [1935] one. However, with the new car the rear axle rides firmly on the road”. 

Since these old hands had previously contributed to the Model 1936’s development, young Uhlenhaut tried driving himself – after they had left the Nürburgring. He showed enormous natural talent, recalling “I realised that a racing car was much the same as a passenger car – there’s not very much difference, nothing sensational”. He traced the front suspension deficit to the system’s anti-shimmy bushings, and identified inadequate steering geometry as fostering excessive toe-in change. He also found the soft suspension was running out of free movement, allowing persistent bottoming which caused the juddering and steering kick about which Caracciola and Brauchitsch had been bitching. 

Uhlenhaut also found that both the chassis frames of the 1935 and 1936 cars and the 1936 de Dion-style rear suspension ‘Y’ tube needed stiffening; bending under stress and vibrating badly. He made 23 recommendations in all.

Entries were then confirmed for the Swiss Grand Prix on August 23, 1936, where different problems intruded after Caracciola had led – before Rosemeyer’s rear-engined Auto Union had flashed past him. Uhlenhaut reported “The drivers declared themselves generally satisfied with the roadholding” but that “…it was clearly evident that the power of the Auto Union car in the middle and upper speed ranges is far superior… A further participation in racing with the E-motor seems to be useless”. 

Bowing to the inevitable, Mercedes-Benz entries in the Italian Grand Prix, the last of the year, were cancelled. From the rubble of that 1936 racing programme, the Stuttgart engineers would then produce the more sophisticated 1937 W125 straight-eight design, with 5.66-litre supercharged engine which proved the most powerful Grand Prix power unit devised until the turbocharged era of the early 1980s. For 1937 it would be Auto Union who had to sweat blood.

Endurance pacing

Group C produced many a drama – sometimes by accident

In the high summer of 1986 – 30 years ago – the Kouros 1000Km races at the Nürburgring and Spa were two of Group C endurance racing’s more extraordinary contests. At the rain-swept Nürburgring Ray Bellm’s Spice SE86C and Jean-Claude Ferrarin’s Isolia-BMW collided. The pace car deployed while the track was cleared, initially picking-up Jacques Heuclin’s slow ALD-BMW with the rest of the field rapidly closing up behind. 

But Hans-Joachim Stuck in his Rothmans Porsche 962 was so engaged in his pursuit of Mike Thackwell’s Sauber-Mercedes that he rushed up onto the tails of Mauro Baldi’s Porsche 956 and James Weaver’s Kremer Porsche 962. As this trio entered the pit straight, each driver was unaware of the pace car’s presence. Weaver began passing slow-moving balls of spray, then realised the reality and braked hard. Baldi promptly rammed him, spinning both cars through the pace-car queue. 

Meanwhile, the pace car driver himself had reached the site of the C2 collision debris, and braked. His followers swerved in avoidance, including Jochen Mass whose 962 was promptly rammed at high speed by Stuck. Both works Porsches – chassis ‘003’ and ‘004’ I believe – were severely damaged, whereupon the organisers stopped the race, and restarted it as a three-hour affair, won by Mike Thackwell and Henri Pescarolo’s Sauber-Mercedes.

At Spa the race became a tactical duel between pole-sitter Thierry Boutsen/Frank Jellinski’s Brun-entered 962C, the Derek Bell/Stuck works car and the Jan Lammers/Derek Warwick ‘Silk Cut’ Jaguar XJR-6. Towards the end all became seriously concerned by their cars’ fuel consumption.

Boutsen/Jellinski’s Jaegermeister 962 was leading, with Bell/Stuck second but with Derek instructed by Porsche engineer Peter Falk to turn down the wick, letting Warwick through. 

On the very last lap of the 625-mile race, sweeping round the circuit’s back stretch, Boutsen felt his engine spluttering as it struggled to scavenge the last few droplets from its near-empty tank. Warwick rushed up onto the stricken car’s tail into the last corner at La Source. He muscled by, intent upon stealing last-gasp victory, but the Jaguar’s V12 engine then starved – just as the Belgian’s chimed in full-bore. Thierry was fired down the hill and shot across the timing line to win by just 0.8sec, with Bell/Stuck third.

This sensational result prolonged the 1986 Group C Drivers’ World Championship outcome into the final round at Mt Fuji, Japan, on October 6. Derek Warwick’s Jaguar was judged initially to have finished second behind Paolo Barilla/Piercarlo Ghinzani’s winning Joest-entered Porsche 956, only for the result to be changed two hours later, demoting the ‘Silk Cut’ Jaguar to third since the official timekeepers had inadvertently credited it with an extra lap. This gave Bell and Stuck a point lead over Derek so the World title was transferred to them in their absence – since both had left the circuit. Later still, FISA would declare Bell solitary World Champion since at the Norisring earlier in the season, driving solo, he had finished 11th, and Stuck 15th.

Fun and games, eh? As happens so often with over-complicated regulations, it’s those who employ them who end up looking foolish.