SEBRING, Florida -- Frank Biela became the second four-time winner in the history of the Twelve Hours of Sebring, teaming with Emmanuel Pirro and Marco Werner to drive an Audi R10/TDI prototype to a six-lap victory on Saturday.

An Acura prototype finished second in its debut.

The winners led from the fifth hour after their sister Audi lost the lead and four laps during a long pit stop to replace the battery, and then the starter, as the crew tried to figure out the electrical problem that plagued the defending champion team.

Biela, the Monte Carlo driver who also won in 2000, 2003 and 2004, joined Audi's Tom Kristensen as the only four-time winners of America's most prestigious sports car race. Kristensen shared the 2000 victory with Biela.

"This is a special place to win, with all the history,'' Biela said. "I am honored to be listed with Tom as the only four-time winners. And I am happy to help Audi win again here. This is wonderful.''

The winners completed 364 laps around the 3.7-mile (6-kilometer) Sebring International Raceway to give Audi its eighth straight victory at Sebring. It was the third Sebring victory for Werner and second for Pirro.

"It was far from easy,'' Werner said. "We were pushing very hard every time and the car was perfect... I looked at the wall of pictures of all the old guys who have won this race. Wow! Now my picture is on the wall, too!''

Kristensen teamed with Rinaldo Capello and Allan McNish to finish fourth, 11 laps behind.

Acura made an impressive debut, with Indy Racing League star Dario Franchitti joining Bryan Hertz and Tony Kanaan in the Andretti Green Acura ARX-01a for the grueling 12-hour race. They finished second overall and first in the LMP2 class, and Herta led the race overall in the third hour during an exchange of pit stops with the Audis.

Herta was running just a lap down in the ninth hour when a 40-second penalty, because a crew member did not have his goggles on during a pit stop, helped the Audi stretch its lead to two full laps. Then the faster Audi pulled away to the final six-lap margin of victory.

"It's a tremendous effort for Acura in their first ALMS race and Sebring race,'' Herta said. "Everyone at Andretti Green Racing and Acura worked so hard to put this program together -- and in such a short time. I didn't know what to expect here at Sebring. I couldn't image coming out and winning out of the box.''

Third overall went to another Acura, driven by Adrian Fernandez, Luis Diaz and David Martinez, all of Mexico. They were two laps behind Herta's Acura at the finish.

The GT1 class battle was a close one between the two factory Corvette C6-Rs. The No. 4 car of Olivier Beretta, Oliver Gavin and Max Papis finished seventh overall, 17.8 seconds ahead of the No. 3 car of Ron Fellows, Johnny O'Connell and Jan Magnussen.

The finish was most exciting in the GT2 where Jamie Melo survived a 20-second penalty during his final pit stop and then a side-by-side collision in his Ferrari 430 G with Jorg Bergmeister's Porsche 911 GT3 RSR to win the class by 0.202 seconds.

e a spirited charge in the final half hour. Mika Salo and Johnny Mowlem shared the driving duties with Melo to give Ferrari its first Sebring victory since 1998.