e-tron quattro is a little different, though. The R18 sports a four-wheel drive system that powers one axle with an electric motor, while the other gets its juice from a 510 hp V6. The e-tron quattro also has a sibling, the Audi R18 Ultra, which seeks to compensate for the added weight of a hybrid drive train by using extremely lightweight materials, like carbon fiber, wherever possible -- including the gearbox. Both cars will be making their debut at the Le Mans 24 Hour on June 16th. For more details check out the PR after the break.