Porsche and Ford flexed their muscle on the first day of IMSA WeatherTech SportsCar Championship competition, taking the top spots in Friday practice at Road America.

Patrick Pilet topped the opening session of the weekend, turning a 2:06.573 in the No. 911 Porsche 911 RSR. The session started out damp, but a drying track allowed teams to change to slick tires to see out the checkered flag.

Corvette Racing’s Oliver Gavin scored the second fastest time in the No. 4 C7.R, followed by the second Porsche, the No. 912 of Gianmaria Bruni.

In the second session, it was Ford on top with Dirk Mueller leading the way in the No. 66 GT.

Mueller took the top spot with a 2:03.967 ahead of Antonio Garcia in the No. 3 Corvette and Bill Auberlen in the No. 25 BMW M6 GTLM.

The sister Ford GT, the No. 67, came fourth and the No. 911 Porsche fifth to make it all four manufacturers in the top five during the session.

The top five were all within 0.179 of a second of each other over the four-mile Road America circuit.

“Historically, we’ve seen a really great race here at Road America almost every year,” said driver of the No. 24 BMW car, John Edwards.

“Some cars are quick on the straightaway, some have good downforce so the carousel and kink you can make up time.

“I think we’re right there in the ballpark, but the question is who can have the edge in qualifying and who can get the track position for the race.”

The course at @roadamerica always supplies great @IMSA GTLM racing. @JEdwardsRacing thinks their @BMWUSARacing car is up to the challenge! pic.twitter.com/WxnOp7bV6V

— Michelin Alley (@MichelinAlley) August 4, 2017

Changing weather made Friday practice at @roadamerica difficult for @janmagnussen and the @CorvetteRacing team, but they made good progress! pic.twitter.com/pUMLQpRqMN

— Michelin Alley (@MichelinAlley) August 4, 2017

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