1914 Mercedes 18/100 Grand Prix

1914 Mercedes 18/100 Grand Prix

Following the victory in the 1908 French Grand Prix, Mercedes suspended the company's competition program. Instead, the Paul Daimler-led engineering team focused on the development of aero engines. During this period valuable lessons were learned about light weight materials and construction. These were applied when the German manufacturer decided to ready brand new cars for the 1914 French Grand Prix at Lyon.

Leaving little to chance, Mercedes built several experimental six-cylinder engined cars for the 1913 Grand Prix de la Sarthe. Considering the new-for-1914 displacement limit of 4.5 litre and maximum weight of 1100 kg, Mercedes figured a four cylinder engine would suffice. In Mercedes' absence, Peugeot had come to the fore with hugely sophisticated twin-cam, four valve per cylinder engines. These cutting edge machines had taken victories in the 1912 and 1913 French Grands Prix and were certainly the cars to beat in 1914.

Using aero-engine technology, a brand new straight four was developed. It was built on an aluminium crankcase with separate steel cylinders. Welded on the cylinders, the individual heads sported four valves. Keen to do things their own way, Mercedes used just a single overhead camshaft to actuate the valves. The camshaft was driven from the crankshaft by a shaft that was fitted at the rear of the engine. The crankshaft itself was counterbalanced and was forged in the highest grade Austrian steel.

Designed to run at twice the speed of any Mercedes engine that had come before, lubrication of the new 'four' was vital. An intricate system was fitted that combined a wet sump with a high pressure pump. No piston rings were fitted so, by the design, the engine used oil. Additional oil could be fed into the system by a manual pump, to be operated by the riding mechanic. To prevent the plugs from fouling, up to four plugs could be fitted, although the cars raced with three. With an eye on reliability these were powered by two separate magnetos.

The 'M 93654' engine was fed by a single Mercedes up-draft carburettor. The first competition engine to rev over 3,000 rpm, the 'four' produced its peak power of 106 bhp at 3,100 rpm. This was quite an achievement considering no other Mercedes/Daimler engine built up to that point could safely rev over 1,500 rpm. A separately mounted four-speed gearbox was used. This was connected to the rear wheels not through the chains previously used but by a propellor shaft for weight saving reasons.

The chassis of the new Grand Prix racer followed convention with a cross-braced, pressed-steel frame suspended by semi-elliptic leaf springs and solid axles. One of the things carried over from the 1913 experimental cars was the V-shaped radiator and tightly wrapped aluminium body complete with belly pan. To reduce drag even further, even the front axles were 'streamlined'. Unlike most of the rivals the Mercedes '18/100' only featured brakes on the rear axle and an additional transmission brake.

Touted as the most important race yet, the entrants of the French Grand Prix not only represented the respective manufacturers but also their countries of origin. Considering the political tension that was quickly building around Europe, the nationalistic feelings reached boiling points. Mercedes entered five cars and in addition to three Peugeots further high level entries were fielded by Fiat, Opel and Sunbeam. Among the Mercedes drivers was the company's test pilot Christian Lautenschlager, who had surprisingly won the 1908 Grand Prix for Mercedes.

Mercedes' Max Sailer took an early lead in the race but his 18/100 only lasted six of the planned twenty laps. In his wake Peugeot lead driver Georges Boillot gave chase but his style and the added loads from his front brakes required additional tyre changes. The very efficient Mercedes was much kinder on its tyres and required only two sets of tyres for the entire race. Already passed by Lautenschlager, Boillot's Peugeot failed on the final lap. This freed the way for a spectacular 1-2-3 victory for the new Mercedes. Lautenschlager was once again the winner, leading Louis Wagner and Otto Salzer home. The fifth Mercedes had retired early with gearbox problems.

Shortly after the French Grand Prix, War spread across the continent and all racing was suspended. One of the cars had been rushed out of the country for Ralph DePalma to race in the United States. He did so with great verve, winning several races, including the 1915 Indy 500. Pressed for money, Mercedes sold several of the other Grand Prix racers to privateers after the War. Constantly updated by their owners, these were raced with great success until the late 1920s. Among the many victories scored was an outright win in the Targa Florio in the hands of Giulio Masetti.

With wins in the French Grand Prix, the Indy 500 and the Targa Florio, the 1914 Mercedes 18/100 ranks among the finest racing cars ever built. It was also the most advanced car before the War and its long career afterwards showed it was a hard act to follow. During the War one car was closely examined by one W.O. Bentley and especially the valve train of the later Bentleys was inspired by the Mercedes design. Of the six examples built, at least three are known to have survived.

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