Page 1 of 3 Next >> 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. Page 1 of 3 Next >>