GM teams flex on home turf in first Detroit IMSA practice

On-track action at the Chevrolet Detroit Grand Prix kicked off with the first IMSA WeatherTech SportsCar Championship free practice session of the day, with GM cars leading both classes in the first 90-minute session.

In GTP, Earl Bamber led the way in the red No. 31 Cadillac Whelen V-Series.R, posting a best lap of 1m07.182s about 30 minutes after the start of practice.

Dries Vanthoor went second fastest in the No. 24 BMW M Team WRT Hybrid V8 (1m07.328s), leading Nick Yelloly in the No. 93 Acura Meyer Shank Racing ARX-06 (1m07.384s) in third.

Felipe Nasr in the No. 7 Porsche Penske Motorsport 963 (1m07.665s) was fourth. But Nasr’s co-driver Julien Andlauer brought out a red flag halfway through the session, after contact with the wall at Turn 4 caused debris to shed off the No. 7 Penske Porsche. The duo was the first to be penalized with the loss of their fastest lap in qualifying later this evening.

Sandy Mitchell also brought out a red flag in the No. 9 Pfaff Motorsports Lamborghini Temerario GT3 after going off in the runoff at Turn 3, and the No. 9 Lamborghini will also lose its fastest lap in qualifying. Neither incident caused major damage to either car.

Rounding out the top five in GTP was Ricky Taylor in the No. 10 Wayne Taylor Racing Cadillac.

In GTD Pro, the No. 4 Corvette Racing by Pratt Miller Motorsports Z06 GT3.R of Nicky Catsburg set the fastest time and was the only driver below the one-minute, 11-second threshold with a 1m10.921s.

Ben Barnicoat in the No. 14 Vasser Sullivan Racing Lexus RC F GT3 set a 1m11.199s to go second fastest, ahead of the No. 65 Ford Racing Mustang GT3, which set a 1m11.291s in the hands of Frédéric Vervisch.

Alexander Sims put the No. 3 Pratt Miller Corvette fourth on the leaderboard with a 1m11.408s.

Practice 2 starts at 11:30am ET.

RESULTS