Aitken puts Cadillac ahead in first Detroit GP practice

Cadillac Whelen’s Jack Aitken set the fastest time in Friday morning’s first practice session for the Chevrolet Sports Car Classic in Detroit.

The red No. 31 Cadillac V-Series.R led Practice 1 with a best time of 1m07.254s, set in the closing minutes of the 90-minute session. Renger van der Zande, in the No. 93 Acura Meyer Shank Racing ARX-06 was second fastest with a 1m07.605s.

Despite a recent Balance of Performance nerf, the No. 7 Porsche Penske Motorsport 963 still had enough one-lap pace in it to go third-quickest in the hands of GTP championship leader Nick Tandy. He set a 1m07.651s, within four tenths of Aitken’s best.

Ricky Taylor in the No. 10 Wayne Taylor Racing Cadillac was fourth quickest, followed by the two BMW M Team RLL Hybrid V8s of Sheldon van der Linde and Marco Wittmann.

As teams and drivers looked to approach the limit on the rough streets of downtown Detroit, 11 out of the 22 cars in the field slipped down into the runoff areas at least once.

Two of those cars were the No. 40 WTR Cadillac and the No. 9 Pfaff Motorsports Lamborghini Huracan GT3, which brought out a red flag after Louis Deletraz and Andrea Caldarelli went off simultaneously into the escape road at the end of Franklin Street. Both cars were eventually able to continue with the rest of their session, but they will also lose their fastest lap in qualifying later today for causing a red flag in practice.

The two Pratt Miller Motorsports Chevrolet Corvette Z06 GT3.Rs led the GTD PRO class. A string of fastest laps from the No. 3 Corvette of Alexander Sims put him at the top of the table with a 1m10.818s. He went 0.2s ahead of the sister No. 4 Corvette of Nicky Catsburg, who turned in a best lap of 1m11.009s

Marco Mapelli was third fastest in the aforementioned No. 9 Pfaff Lamborghini, just a few thousandths up on championship leader Laurin Heinrich in the No. 77 AO Racing Porsche 911 GT3 R in fourth; Sebastian Priaulx in the No. 64 Ford Multimatic Motorsports Mustang GT3 rounded out the top five in GTD PRO.

UP NEXT: Practice 2 begins at 11:30am ET.

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