Ayhancan Guven set the fastest time in the opening practice session for the Indianapolis 8 Hour as 21 out of 23 cars were separated by less than a second.
The Turkish driver steered the No. 32 GMG Racing Porsche 911 GT3 R to a best lap of 1:23.856, outpacing Earl Bamber Motorsports’ Bastian Buus by 0.039 seconds.
Pro-Am entries made up the entire top five, with Buus followed by the No. 8 Flying Lizard Motorsports BMW M4 GT3 of Nick Yelloly, the No. 10 Herberth Motorsport Porsche and No. 75 SunEnergy1 Racing Mercedes-AMG GT3 Evo.
Connor De Phillippi took sixth as the best Pro entry aboard the No. 99 Random Vandals Racing BMW, ahead of the No. 88 Triple Eight JMR Mercedes-AMG in the hands of Arjun Maini.
Maro Engel slotted into eighth for GruppeM Racing, with Jules Gounon turning his first laps aboard the No. 130 Mercedes-AMG in the closing minutes after arriving at the circuit having traveled from Circuit de Barcelona-Catalunya.
The top ten was completed by Robby Foley and Sheldon van der Linde, with the latter’s No. 31 Team WRT BMW just 0.311 seconds slower than Guven.
In total, 21 out of 23 runners were covered by less than a second, with the last-placed No. 64 DXDT Racing Chevrolet Corvette Z06 GT3.R 1.433 seconds off.
The session was interrupted by two red flags. The first was triggered when the No. 8 BMW of Elias Sabo stopped on the front straight with a gearbox issue after a spin.
The second stoppage, which occurred with just over two minutes remaining in the session, was caused by the No. 88 AF Corse Ferrari 296 GT3 becoming stuck in the gravel.
Track action for the Indianapolis 8 Hour continues with Pre-Qualifying, Friday at 10:45 a.m. EDT.
RESULTS: Free Practice