Night practice at Motul Petit Le Mans, the last practice before qualifying and the race, helps the teams get the setup right for the finish on Saturday night. About a quarter of the race is run after sunset, and much like Sebring, that is often where the race is won or lost. It is also a requirement that each driver do three laps at night to get accustomed to Michelin Raceway Road Atlanta in the dark. Petit Le Mans rookie Kyffin Simpson, driver of the GTD-class No. 66 Gradient Racing Acura NSX, said he’s never raced anyplace so dark.

Whether times in the session indicate who will have the speed in the final hours of the race or not, it was Cadillacs in positions one through five, with the two Acuras fighting for the championship behind. With all the DPi teams within six-tenths of a second, Earl Bamber was back at the top in the No. 02 Chip Ganassi Racing Cadillac with a 1m09.880s lap.

Tristan Vautier was quick again in the No. 5 JDC-Miller Motorsports Cadillac, 0.123s shy of Bamber’s best, followed by Renger van der Zande in the No. 01 CGR Cadillac. The 01 had an unusual incident during the session, losing a wheel and parking in Turn 7. The most bizarre aspect of the incident, though, was the wheel nut getting flung forward and taking out the headlight of the Cadillac.

The two Action Express Racing machines driven by Pipo Derani (No. 31) and Kamui Kobayashi (No. 48) completed the Cadillac sweep of the top five.

The two LMP2 contenders were at the top of the timesheet, Louis Delatraz in the No. 8 Tower Motorsports Oreca besting Ryan Dalziel in the No. 18 Era Motorsport ORECA by 0.739s. The LMP2 laps have been remarkably close to the DPi on time, with the top times in this session less than a second apart.

The top contenders for the LMP3 championship both packed up early in the session, with Felipe Fraga in the No. 74 Riley Motorsports Ligier ahead of Colin Braun in the No. 54 CORE Autosport Ligier. But it was Gabby Chavez who was quickest in the No. 36 Andretti Autosport Ligier with a time of 1m16.028s.

Lexus was on top again in GTD, as Aaron Telitz posted the fastest GT time overall with a 1m19.815s lap in the No. 12 RC F. Just behind him was the leading GTD PRO car, the No. 62 Risi Competizione Ferrari 488 in the hands of James Calado at 1m19.649s. The GTs were well mixed up, with Bryan Sellers third overall in the GTD-category No. 1 Paul Miller Racing BMW M4 GT3, 0.183s off Telitz’s best. Jack Hawksworth just missed putting Lexus atop both classes, posting the second-quick GTD PRO time, 1m19.867 in the No. 14.

Toni Vilander (No. 21 AF Corse Ferrari), and Maximilian Goetz (No. 79 WeatherTech Racing Mercedes-AMG) completed the top three in GTD and GTD PRO, respectively.


Up next: The IMSA WeatherTech SportsCar Championship drivers have most of the day off on Friday, with the only session qualifying that takes place at 3:40 p.m. Eastern.