The Chevrolet Corvettes have shown they can take the fight to the crack Vitaphone Maserati squad in this weekend's Spa 24 Hours after the opening hour of the race.
Vitaphone's MC12s qualified one-two-three in a rain-interrupted session on Thursday, but the three Corvettes moved through early on in the race this afternoon.
At one stage ex-Formula 1 racer Enrique Bernoldi led in the Sangari Team Brazil C6.R from the Selleslagh Racing Team car of Oliver Gavin after both worked their way past the Maseratis.
Bernoldi fell back in a rain shower after around 40 minutes, but Gavin built a lead of over 10 seconds before the first round of scheduled pitstops. The Briton stayed aboard and currently leads the #1 MC12 of Andrea Bertolini by around 25s.
Mike Hezeman's Pekaracing Corvette lies third at present, ahead of a battle between Bernoldi and Pedro Lamy in the #2 MC12 started by poleman Alex Muller.
GT2 is led by the IMSA Performance Porsche 911, in which Patrick Pilet pulled clear of ex-F1 driver Gianmaria Bruni (AF Corse Ferrari 430) during the opening hour. Pilet now leads Bruni's co-driver Jaime Melo by 15s.
Like the GT2 Porsche, the GT3 911 appears to be able to run longer between stops than its class rivals. Niki Lanik stayed out the longest of the frontrunners to take the GT3 lead, but has just lost out to the faster Ford GT of Thomas Mutsch.
The Phoenix Audi of Marcel Fassler comfortably leads the G2 category and has established itself in the top 10 overall.
The works Nissan of Michael Krumm is the leading 2010-generation GT1, with its only rival losing time in the pits. The Marc VDS Ford GT came in after just half an hour with a gearbox problem and has still not returned to the track.