8 hour update: Audi quartet still in front

Tom Kristensen now leads the race by an ever-increasing margin over Michele Alboreto as dusk sets in at the Florida circuit and ominous-looking clouds roll in from the south east.

Alboreto is obviously having another 'off Sebring', lapping slowly and then incurring a pitlane speeding penalty. This hiatus enabled Guy Smith to lead briefly in the Gulf Audi before pitting to replace both front discs (losing five laps in the process). Kristensen cruised up behind Alboreto and passed his team mate easily, then built up a 15sec cushion. The Champion R8 reaped the benefit of its cautious early pace and Dorsey Schroeder looks comfortable in third.

Both Panoz cars are now out. The Salles/Graf car sat out most of the first four hours in the garage and only managed another 14 laps before retiring with a suspension breakage. Gearbox failure accounted for the Brabham/Magnussen car after it had completed 109 laps.

Eliott Forbes-Robinson parked the Thetford Dyson Riley & Scott MkIII C on pitlane in the fifth hour, the Lincoln-badged engine disgorging its vital fluids over the rear bodywork. Jon Field's Lola-Judd is the only other prototype left running.

The Konrad Saleen S7-R now has a comfortable but not unassailable lead in GTS. Terry Borcheller chased down Andy Pilgrim's Corvette in the sixth hour while Chris Kniefel's car sat on its jacks in pitlane. The Pilgrim car has since had a brake pad change, losing a lap, but the Saleen may need to follow suit.

Emmanuel Collard leads GT in the McKenna Porsche 911 GT3-RS. As expected, the Porsche's frugality (relative to the Schnitzer BMW's V8 engine) has enabled it to make fewer stops. The Lehto/Muller M3 made an unplanned but brief visit to the pits at the eighth hour mark. It's surprising the car's clutch has made it this far, because its propensity to stall forces both drivers to make violent getaways. The third-placed Pobst/Menzel/Bernhard McKenna Porsche has dropped off the lead lap after seeming to be inseparable from its team mate in the opening hours.

Biela/Kristensen/Pirro Audi R8 248 laps
Capello/Alboreto/Aiello Audi R8 248
Kelleners/Schroeder/Wallace Champion Audi R8 245
Johansson/Smith Gulf Audi R8 243
Konrad/Borcheller/Gavin Konrad Saleen S7-R 222
Pilgrim/Collins/Freon Chevrolet Corvette C5-R 221
Luhr/Maassen/Collard McKenna Porsche 911 GT3-RS 219
Lehto/Muller BMW M3 GTR 218
Field/Dayton/Sutherland Intersport Lola-Judd 218
Pobst/Menzel/Bernhard McKenna Porsche 911 GT3-RS