Audi R15 & Peugeot 908 HDI FAP - Million-Dollar Diesels

Cars may not be your thing, and the idea of road racing may only conjure images of Jean Girard from the movie Talladega Nights, but if you're reading Diesel Power, we know you're into high-performance diesels. Seeing as how that's the case, it would be irresponsible for us not to bring you up to speed on what may be the highest performance diesel vehicles in the world: the Audi R15 and the Peugeot 908 HDi FAP

Both of these cars were built to win the 24 Hours of Le Mans endurance race that runs every June near Le Mans, France. Audi debuted its diesel R10 race car back in 2005, six months before the Peugeot 908, and has now moved on to its second-generation diesel racer-the R15 you see here. Both cars battled it out on American soil at the 12 Hours of Sebring in March, and Diesel Power was on hand to soak in the technology. After 12 hours of racing, the new Audi R15 defeated the Peugeot 908 by 22.279 seconds, but the real test of these cars will come on June 13, 2009 when they meet again at Le Mans.

The Audi R15's all-new 5.5L...        read full caption The Audi R15's all-new 5.5L V-10 diesel (rated to make more than 600 hp and 775 lb-ft) was much more difficult to get a photo of. Audi told us the engine uses the same architecture (twin Garrett turbos, Bosch common-rail injection, aluminum block and cylinder heads) as the R10's 5.5L V-12, but the new engine makes do with two less cylinders, which shortens it 4 inches and reduces its weight by 10 percent. We took note of the new 3-1/2-inch titanium stacks that route the exhaust up toward the rear wing to create additional downforce.	At the Audi pit, the action...        read full caption At the Audi pit, the action began much earlier in the morning. Unlike Peugeot, Audi pulled its cars in forward so the technicians could run the engines' exhaust straight out of the tent. This setup prevented us from getting anywhere near the cars while the rear body panels were off. In fact, even when the engines were exposed, they were almost always covered with sheets of gray material. The good news is that when the 5.5L V-10s fired up and idled, they had a familiar diesel engine sound. When the cars were whipping around the track at 5,000 rpm you could barely hear the engines at all.	The Audi R15 cockpit looks...        read full caption The Audi R15 cockpit looks sparse by comparison, which makes sense because clutter in the open-top car could have a negative impact on aerodynamics, considering it averages 128 mph around the 3.7-mile Sebring racetrack. All of the R15's information is conveyed to the driver via this steering-wheel mounted digital display. Evidently English is the unofficial language of Audi's race program, because none of the indicators or warnings are in German.
	Just one of these Audi R15...        read full caption Just one of these Audi R15 carbon-fiber front clips probably costs as much as our diesel truck. Each one is fitted with new LED-based headlights that Audi plans to bring into production soon. Luckily, on the days we were at Sebring, none of the cars were involved in any wrecks.