Rule changes for the 2011 Le Mans mean Audi has moved to a closed-cockpit design after more than a decade using roofless prototype cars.
Audi is sticking to turbodiesel power, despite the fact that the regulations have changed, reducing the maximum allowable capacity from 5.5 litres to 3.7 litres.
According to Audi's motorsport boss, Dr Wolfgang Ullrich, the company wasn't keen to switch to a fixed-roof car, but the new regulations made it the only sensible option.
"The rules mean you have to have a roof to be competitive," he said. "Driver changes are always easier with open cars, but the changes have taken that away. The smaller-capacity engines also make aerodynamic efficiency more important."
Peugeot 908's latest addition), and striking LED headlights, which include a (dare we say 'gauche'? - yes, we do) set of daytime running lights that form the shape of a number '1'.
The R15-plus isn't dead yet, though - it will compete in the Sebring 12 hours early next year, while the R18 will not make its race debut until Spa in May, before heading to Le Mans.