Audi is back with the quattro, only a Le Mans prototype this time. Boasting the e-tron technology, the LMP1 car is the first to be powered by a hybrid powertrain, supported by a diesel engine.
Christened, Audi R18 e-tron quattro, the Le Mans prototype will make its race debut on May 5. The six-hour hour qualifier is to be held at Spa-Francorchamps in Belgium, where it will fight to qualify for the main event scheduled on June 16/17.
“Audi has always consciously selected championships and categories in racing that have a close relationship to production and therefore have technical relevance for the Audi customers,” explains Head of Audi Motorsport Dr. Wolfgang Ullrich, who personally drove the new Audi R18 e-tron quattro onto the stage on Wednesday evening during its world premiere in the Audi Training Center at Munich airport – electrically and almost silent. “quattro, TFSI and TDI are three excellent examples of how motorsport has stimulated production development. A similar tendency is apparent with the e-tron quattro: we test a completely new technology on the race track before it’s introduced to the Audi production line.”
The operating principle of the R18 e-tron quattro starts with a kinetic energy recovery braking system on the front axle which sends electricity into a flywheel accumulator before being sent back down to the electric motors on the front wheels. Energy from the accumulator can only be retrieved under acceleration above 120 km/h (74 mph).
The R18 e-tron features Kinetic Energy Recovery System, that recovers the energy on the front axle during braking. This energy is retrieved during acceleration above 120k mph at the flywheel accumulator and delivered to the front axle. Meanwhile, a V6 TDI power plant producing over 510 hp continues transmit power to the rear wheels. It is similar to KERS in Porsche 911 GT3 Hybrid, which uses petrol in support of electricity on the rear and cannot work on sole electricity.
Audi started working on the new hybrid from February 2010. Only 18 months passed from the initial conceptual ideas to the first test. “This is a relatively short cycle for a technology that has never been tested in motorsport and which still doesn’t even exist in production,” stresses Dr. Martin Mühlmeier, Head of Technology at Audi Sport. “The challenge is correspondingly big.”
In addition to the R18 e-tron, Audi Sport also developed the R18 Ultra to compete in the Le Mans. This quatto features the same base of the R18 e-tron but without the hybrid drive. The trick is to build the lightest Le Mans racer, Audi Sport has ever made.
“The TDI engine invented by Audi is still the most efficient drive in the world,” says Dr. Wolfgang Ullrich. “We are convinced that the TDI has even more potential. This is why Audi not only supports the hybrid in motorsport as it does in production, but in parallel also the further development of the conventional drive.”
To compensate for the additional weight of the hybrid system, Audi focused purely on the keeping the structure as light as possible throughout the development of the 2011 Le Mans winner. Moreover, Audi Sport also developed a new transmission system with carbon fiber composite housing for the R18 racer.
“The new R18 ultra is a distinct evolution of last year’s Le Mans race winning car,” summarizes Head of Audi Motorsport Dr. Wolfgang Ullrich. “Our drivers’ impressions were very positive from the first moment. Without the weight optimized R18 ultra we would have not been capable of realizing the R18 e-tron quattro which is absolutely identical with the exception of the hybrid system.”
Audi Sport Team Joest will field two R18 e-tron quattro and two R18 ultra prototypes in the Le Mans 24 Hours on June 16/17. The two hybrid cars are driven by last year’s winning trio Marcel Fässler (CH), André Lotterer (D) and Benoît Tréluyer
