Audi reigned supreme within the 24 Hours of Le Mans for many years. The German team's prominence deterred any other producer from improving, leaving privateer teams like Pescarolo Sport as Audi's only challengers. All this changed when Peugeot joined the fray in 2007 using the 908 HDI Fap. Its very efficient design shown hard to beat, driving the German engineers to new extremes with combined outcomes. Strong team performance and great driving nevertheless transformed the tables in Audi's favor three times in the last four years. The most significant of these changes is a cut in maximum displacement of a third for the diesel engines favored by both Audi and Peugeot.
With considerably less power available, efficiency became the key word through the development of the new Audi R18. This inspired that Audi R18 engine to believe outside of the box and create a machine that is both a visual and mechanical departure from its predecessors. After extensive calculations, the designers arrived at the conclusion that a closed car was the only way to go; the lower drag figures far outweighed the possible drawbacks like the slower driver changes.
Learn more on Audi R18
Going for a coupe nevertheless has not been a decision taken casually as all of Audi's victories at Le Mans were scored with open cars and the only fixed head prototype the Germans ever fielded, the R8C of 1999, has not been a success. Although the overall configuration of the Audi R18 is different, it does share lots of aerodynamic cues with the R15, particularly the 'platypus' nose and the very low 'side-pods'. In fact, the side-pods on the R18 are even lower than on the R15. This is achieved by a very unique layout of the all-new V6 diesel engine. As the result of utilizing only one turbo, the R18 engine also needed only a single exhaust system and particulate filter. The triangular exhaust exit is available directly underneath the rear wing mount. After being fed through intercoolers, the charged air is fed to the cylinders from the underside. According to official figures the compact V6 engine produces more than 540 bhp but just how much more we shall most likely not know any time soon. While the previous Audi diesel prototypes sufficed with just five forward speeds, the R18 features a new six-speed gearbox that is again an outcome of the cut in power and torque.