Just one month before the factory opening, Audi starts the crucial phase of the FIA World Endurance Championship (WEC) in Mexico. Five of the nine championship races on the calendar are held between September and November. The world tour begins with the first ever world championship race in Mexico City on September 3. For drivers and engineers alike, it is the altitude of the 4.304 kilometre track that represents the biggest change: at a height of more than 2,000 meters above sea level the air is quite literally rarified.
André Lotterer raced here 14 years ago in the ChampCar series. “The fans screamed so loud and excitedly that I had to cover my ears during the driver parade,” remembers Lotterer. Marcel Fässler and Oliver Jarvis experienced the enthusiastic fans nine years ago in the A1GP championship – Jarvis even flew home with a winner’s trophy. And last March, Lucas di Grassi and Loïc Duval raved about the public’s warm reception after the FIA Formula E race in Mexico. The unusual track also runs through a baseball stadium. Benoît Tréluyer is the only Audi driver never to have competed in Mexico in his career.
The six-hour race makes great demands of the six drivers’ fitness. The Autódromo Hermanos Rodríguez lies at an altitude of almost 2,300 meters. As a result, the air is about 25 to 30 per cent thinner than at sea level. The Audi Sport engineers have prepared meticulously for this. The Audi R18 diesel hybrid sports car reaches higher speeds on the straights, as the air resistance sinks. In turn, the lower air density is a disadvantage in corners.
The engine is also affected by the thinner air. The V6 TDI power plant is supplied with air by a turbocharger. Up to now, this has compressed the intake air fourfold, for Mexico the regulations now permit five times the value. Thus, the altitude-related loss of power can to a large extent be compensated for. “However, the higher compression also increases the charge air temperature, which is why we run with adapted cooling,” says Ulrich Baretzky, Head of Engine Development at Audi Sport. A high-altitude application for the engine electronics completes the changes.
Mexico is of special importance for Audi: at the site in San José Chiapa, the company opens at the end of September its most up-to-date production facility, in which the new Audi Q5 will roll off the production line in the future.
The 6-hour race in Mexico starts on Saturday, September 3.
