AutoblogGreen

The Detroit Grand Prix is taking place this weekend at a temporary course on Belle Isle in the Detroit River. While the diesel-powered Audi R10s are well known in these parts for their dominance, all the racers here this weekend are running alternatives. Aside from the Audis all the other non-diesel cars are running a spec fuel that is comprised of ten percent ethanol and the rest gasoline. In future years, the ALMS organizers are planning to increase the use of the biofuels.

For the Sunday racing action with the Indy Cars, all the racers are running one hundred percent ethanol this year. One interesting note this weekend has been the performance of the Audis. While the R10 has been dominant since its debut at the beginning of 2006, they only qualified seventh and eighth here. The huge torque output of the diesel V-12 has proved difficult to put down on the tight and bumpy 2.1 mile course on Belle Isle. It just goes to show you that even being the most fuel efficient car on the track doesn't mean you can't have too much power too. At the end of the day the Audis overcame their traction problems and finished second and third overall behind the Porsche RS spyder of Romain Dumas.