The long racing season for the Audi Sports Team Joest begins in March at the 12 Hours of Sebring. On the agenda for the season that runs up to November are seven races, the Le Mans test weekend and numerous tests with the Audi R15 TDI and the new Audi R18, which does not race at Sebring. In order not to interrupt preparations for the 24 Hours of Le Mans on June 11/12, the test and development program with the R18 continues to run in parallel to the opening round of the Intercontinental Le Mans Cup 2011 (ILMC) season.
As a result, one car in particular will bid its farewell at the 12
Hours of Sebring, a car that made its debut here two years ago: the Audi
R15 TDI. It celebrated its 2009 premier with a victory which was the
ninth for Audi in this traditional event in the U.S. state of Florida
since 2000.
For this second appearance at Sebringthe diesel racing sports car will be competing under completely different conditions due to the new technical regulations announced by the Automobile Club de l'Ouest (ACO.) To comply, Audi has developed the "closed cockpit" R18. Older models like the R15 TDI may only compete in heavily modified forms with greatly restricted engine power. Just how these cars will fare against the new models remains to be seen.
Drastic cuts in technology
The new LMP1 prototype regulations limit engine displacement for new models such as the Audi R18 to 3.7 liters. For older vehicles like the Audi R15 TDI, the 5.5 liter V10 must now draw intake-air restrictors of 33.5 mm diameter—this is 4 mm less than before. At the same time, boost pressure is reduced by 23 percent to 2,000 millibar—2,590 millibar was allowed previously. The fuel tank will only contain 65 rather than 81 liters of diesel and the fuel flow restrictor in the autonomous refuelling tank has also been reduced by 5 mm to 28 mm.
"The drivers felt the engine restrictions very early during the test in Florida. They miss several dozen horsepower," explains Ralf Jüttner, technical director of Audi Sport Team Joest. "The reduction in tank volume sounds drastic at first, but the engine obviously also consumes less. The slower flow rate from the external tank means that pit stops will certainly not be any shorter despite the smaller fuel tank volume."
Proven drivers, new partners
The Audi R15 TDI makes its farewell appearance in Florida in the hands of two successful driver lineups; Timo Bernhard and Romain Dumas, who won at Sebring in 2008, share the car with start number "1" with Mike Rockenfeller. Dindo Capello, Tom Kristensen, and Allan McNish, the Sebring winners in 2009, drive the number "2" numbered Audi.
Two new corporate partners are also part of the team for the first time at Sebring. Alongside Bosch, Mahle, Michelin, and TAG Heuer, partnering with the Audi sports car program for 2011 are Alpinestars, specialists for motorsport and extreme sports clothing as well as street wear and, the return of familiar face to Audi Sport, lubricant manufacturer, Castrol.
Questions that people will be looking to answer race weekend:
• How fast is the R15 TDI, which should actually be called "R15 plus
minus" after being modified to comply with the new regulations?
• Can Audi exploit the reliability of the established R15 TDI around the tough Sebring track with its experienced drivers on board?
• How will the balance differ between the modified 2010 cars, the Audi R15 TDI and new LMP1 models?
The 2011 12 Hours of Sebring race begins at 10:30AM EDT on Saturday March 19th.