Luhr and Werner win at St Petersburg

Luhr and Dumas ran side-by-side several times along the pit-straight in the last half an hour of a crash-strewn, chaotic encounter on the 1.8-mile street track.

But in the end, the nimble LMP2 RS Spyder simply couldn't match the torque of the powerful diesel-powered LMP1 TDI into Turn One, and following a final late-race caution period Luhr ran off the final laps to take the victory.

There was consolation for Dumas and teammate Timo Bernhard, who notched up the team's 13th consecutive victory in LMP2.

David Brabham brought the Highcroft Racing Acura home third after a similarly intense battle with the sister Penske Porsche driven by Patrick Long, which was at the centre of more than one excursion on a track that put precise passing of back-markers at a premium.

Both drivers inherited their positions however, after the Dyson Racing Porsche Spyder of Guy Smith peeled into the pits from a secure third position at the end of the previous caution period with a slow puncture.

The Englishman, a former Le Mans 24 Hours winner, finally finished a disappointing fifth ahead of the Andretti Green Racing Acura driven by Bryan Herta and Christian Fittipaldi.

Luhr's Audi was in fact the only LMP1 car to make the finish in a race that witnessed three multi-car accidents. The sister Audi, driven by Frank Biela and Emmanuele Pirro, was retired after the Italian made an ill-advised attempt to pass Adrian Fernandez's Acura at Turn Four on lap 64, 90 minutes into the two-hour race.

The Mexican would return to the track to bring the Lowe's car home seventh in the LMP2 class.

Jon Field's Intersport Lola LMP1 also retired after sustaining heavy damage when he spun while trying to defend sixth position on lap 34, bringing out the second of four caution flags.

Perhaps the biggest shunt of all however came about when Long clipped Joel Feinberg's Dodge Viper while lapping him. Feinberg could only sit and watch as his prone car was hit hard by Terry Borcheller's Aston Martin. Both cars were heavily damaged, both drivers were not, but the operation to clean up the debris was significant and lengthy.

Indeed the casualty rate was high in the competitive GT2 category, with both Risi Competizione Ferraris running into trouble. The front-running car of Mika Salo and Jaime Melo nearly cooked the Finn when the air conditioning broke, forcing the former Formula One driver to pit earlier than scheduled.

Then as Melo embarked on a comeback drive, the electronics on the F430 GT gave up for good.

The sister car of Patrick Friesacher and Harrison Brix was also running strongly when the Austrian former Minardi driver shot off down an escape road having clipped Butch Leitzinger's spun Dyson Porsche Spyder - the American having lost control while fighting the hard-charging Long.

Through all the carnage came Dirk Muller in the Tafel Racing Ferrari to take the win. The German had in fact passed Flying Lizard Porsche driver Jorg Bergmeister on track for the lead of GT2 before the latter also collected Leitzinger's stricken Spyder.

Even the normally sedate GT1 category had drama as the two factory Corvette C6.Rs changed position on the last lap with the Oliver Gavin/Olivier Beretta example beating that of Jan Magnussen and Johnny O'Connell.

Pos  Cl  Drivers                          Car                   Laps
 1.  P1  Luhr/Werner                      Audi R10 TDI          81
 2.  P2  Dumas/Bernhard                   Porsche RS Spyder     81
 3.  P2  Brabham/Sharp                    Acura ARX-01b         81
 4.  P2  Maassen/Long                     Porsche RS Spyder     81
 5.  P2  Dyson/Smith                      Porsche RS Spyder     81
 6.  P2  Herta/Fittipaldi                 Acura ARX-01b         80
 7.  P2  Bonilla/Devlin                   Mazda Lola B07-46     80
 8.  GT  Gavin/Beretta                    Corvette C6.R         79
 9.  GT  O'Connell/Magnussen              Corvette C6.R         79
10.  P2  Fernandez/Diaz                   Acura ARX-01b         78
11.  GT  Farnbacher/Muller                Ferrari 430 GT        77
12.  GT  van Overbeek/Pilet               Porsche 911 GT3 RSR   77
13.  GT  Werner/Basseng                   Porsche 911 GT3 RSR   76
14.  GT  Jeannette/Mowlem                 Ferrari 430 GT        76
15.  GT  Brix/Friesacher                  Ferrari 430 GT        75
16.  GT  Hand/Milner/Sutherland           Panoz Esperante       75
17.  GT  Neiman/Law                       Porsche 911 GT3 RSR   74
18.  GT  Gigliotti/Peterson               Riley Corvette C6     74
19.  P2  van der Steur/Pecorari           Radical SR9 AER       74
20.  P2  Leitzinger/Franchitti            Porsche RS Spyder     71
21.  GT  Bergmeister/Henzler              Porsche 911 GT3 RSR   71
22.  GT  Salo/Melo                        Ferrari 430 GT        69
23.  GT  Robertson/Murry                  Doran Ford GT Mk.VII  64
24.  P1  Biela/Pirro                      Audi R10 TDI          63
25.  GT  Borcheller/Ducote                Aston Martin DBR9     48
26.  P1  Field/Dayton/Berry               Lola B06/10 AER       33
27.  GT  Feinberg/Hall                    Dodge Viper Comp Cou  20
28.  GT  Carrapatoso/Swartzbaugh/Stanton  Porsche 911 GT3 RSR   - 
29.  GT  Drayson/Cocker                   Aston Martin DBRS9    -