Click above for a high-res gallery of the Audi R25 concept from the 2008 LA Design Challenge

Racing fans young and old, near and far have been eagerly awaiting the launch of the new Audi R15, but they'll have to wait a bit longer. The successor to the eminently successful R10 TDi isn't scheduled to make its debut until the 12 Hours of Sebring in March.

Little is known about the R15, but Audi's racing division has been hard at work -- burning the midnight oil, you could say -- developing the LMP1 racer, having recently undergone a thorough shake-down at an undisclosed track in Spain with Le Mans winners Allan McNish, Tom Kristensen and Rinaldo Capello alternating behind the wheel. The smart money is on the R15 adopting a closed-cockpit body-style, and Audi will be sure to make the new R15 even faster and greener than the record-breaking R10 in an effort to stave off Peugeot's new 908HY. But after puling out of the full Le Mans and American Le Mans Series, the only time we'll actually get to see the R15 in action will be at the 24 Hours of Le Mans and the 12 Hours of Sebring later this year.

[Source: Autosport]