Jack Aitken was the fastest driver during the IMSA SportsCar Championship’s opening free practice session for the Detroit Grand Prix.
The 90-minute session began the track action for the Sportscar Classic at the second of the calendar’s two street circuit events.
Twenty-two cars took to the streets of Detroit to begin gathering mileage and data in preparation for the 100-minute race tomorrow, Saturday, 31 May.
Being a street venue, there are a limited number of run-off areas drivers can exploit during their familiarisation process with the bumpy and tight track.
Numerous cars found themselves in the run-offs at Turns 1 and 8. However, it was a tangle between #40 Wayne Taylor Racing (WTR) Cadillac V-Series.R driver Louis Deletraz and #9 Pfaff Motorsport Lamborghini Huracan GT3 EVO2 driver Andrea Caldarelli, which caused a temporary stoppage.
Though it was a brief clash between the two at T1, quickly continuing on their way after the red flag was called, they will both likely lose their fastest lap time during qualifying as a result of causing the brief stoppage – instead using their second-fastest qualifying lap time.
Aitken quickest, Corvette 1-2 in GTD Pro

At the end, Aitken was the fastest for the #31 Whelen Cadillac GTP entry with a 1:07.254 lap time, 0.351 seconds ahead of Renger van der Zande’s #93 Meyer Shank Racing Acura ARX-06 GTP in second place.
Nick Tandy, last year’s pole-sitter, took third in the championship-leading #7 Porsche Penske 963 GTP as he set a 1:07.651, followed by Ricky Taylor’s #10 WTR Cadillac, which set a 1:07.670.
BMW RLL finished in fifth and sixth positions, as Sheldon van der Linde’s #25 BMW M Hybrid V8 beat the #24 of the driver who has claimed all pole positions so far this season, Dries Vanthoor.
In GTD Pro, Alexander Sims set the quickest lap time at the wheel of the #3 Corvette Z06 GT3.R, a 1:10.818, followed by the #4 Corvette driver Nicky Catsburg, who posted a 1:11.009.
Lamborghini driver Marco Mapelli was third in the #9 Pfaff Lamborghini after his 1:11.138.
AO Racing’s ‘Roxy’ Porsche 911 GT3.R took fourth after reigning Drivers’ champion and class winner from last year, Laurin Heinrich, set 1:11.152.
Seb Priaulx, who joined Heinrich on the top podium step last year, rounded out the top five in the #64 Ford Multimatic Mustang GT3 with a 1:11.336.
See here for the full results. FP2 commences at 11:30 ET or 16:30 BST.