Jack Aitken’s No. 31 Whelen Cadillac V-Series.R topped the opening IMSA Watkins Glen practice for the 2025 Sahlen’s Six Hours of The Glen.
The 3.4-mile track, nestled in the rolling hills of upstate New York’s Finger Lakes region, provided a challenging canvas for the 56-car grid, with drivers eager to maximize their limited practice time ahead of the grueling six-hour race.
Teams and drivers arrived with high expectations, and the field—comprising the latest generation of GTP prototypes, LMP2 machinery, and GTD contenders—did not disappoint, delivering a practice session marked by pace, precision, and a few dramatic interruptions.
The 90-minute opening session began under dry but variable conditions, as many teams had anticipated possible rain and adjusted their run plans accordingly.
The session’s early laps saw a flurry of activity as teams sought to gather crucial data on tire performance, fuel consumption, and car balance, all while keeping a wary eye on the skies for any sign of changing weather.
Jack Aitken piloting the red No. 31 Whelen Cadillac V-Series.R for Action Express Racing, emerged as a standout performer.
Coming off a disappointing result at the Le Mans 24 Hours, the British driver delivered a blistering lap of 1:34.584, coming within four-tenths of the GTP lap record and putting Cadillac at the top of the time sheets.
Close behind Aitken was Nick Yelloly in the No. 93 Meyer Shank Racing Acura ARX-06. Yelloly who recently celebrated a victory at Detroit and a Le Mans triumph, continued his strong form with a lap of 1:34.966.
His time was only a few hundredths faster than Tom Blomqvist who was back in the blue No. 60 Acura after a stint in IndyCar. Nick Tandy set the fourth-fastest time in the championship leading No. 7 Porsche Penske Motorsport 963.
Louis Deletraz driving the No. 40 Wayne Taylor Racing Cadillac rounded out the top five, ensuring that multiple manufacturers were represented at the sharp end of the field.
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BMW’s challenge was led by Marco Wittmann in the No. 25 Team RLL M Hybrid V8 who finished within a second of the top time. The No. 23 Aston Martin THOR Team Valkyrie and the returning No. 63 Lamborghini Squadra Corse SC63 also featured in the top half of the GTP order.
In the LMP2 category, the No. 74 Riley Oreca went fastest in the hands of Felipe Fraga edging the No. 22 United Autosports entry piloted by Paul Di Resta.
The GTD Pro class saw Andrea Caldarelli set the fastest lap in the No. 9 Pfaff Motorsports Lamborghini Huracan GT3 EVO2.
However, he was edged by GTD’s Scott Andrews who set the pace in the No. 80 Lone Star Racing Mercedes-AMG GT3 Evo, followed closely by Alec Udell in the No. 36 DXDT Racing Chevrolet Corvette Z06 GT3.R.
The the opening IMSA Watkins Glen practice was not without incident. Two red flags disrupted the flow, both caused by incidents involving the No. 8 Tower Motorsports LMP2 Oreca.
John Farano was the first to encounter trouble, crashing at the entrance to the Esses and sustaining rear-end damage. The car limped back to the pits only for co-driver Charlie Eastwood to suffer a heavier crash at Turn 7 with just 14 minutes remaining.
The second incident required barrier repairs and a lengthy cleanup, reducing the amount of green-flag running available to teams. The session resumed with less than five minutes to go but the limited time meant that few drivers were able to improve their lap times.
Practice 2 for Sahlen’s Six Hours of The Glen is scheduled for Saturday at 9 a.m. EST.
