While BMW Team RLL initially struggled to comes to grips with Michelin’s new WEC-spec tires that debuted at Mazda Raceway Laguna Seca, the German manufacturer now believes it’s closer to unlocking their full potential in order to close the gap to the competition in the GT Le Mans class.
BMW experienced one of its worst races in the Continental Monterey Grand Prix at the beginning of May, with the two M6 GTLMs finishing last in class as they got their first taste of Michelin’s new rubber.
“It’s always difficult to say, as there are so many influencing factors,” BMW Motorsport director Jens Marquardt told Sportscar365.
“Obviously we felt that it was going quite well in IMSA up to Laguna Seca, but then we were definitely struggling with those tires that for us were new there.
“We didn’t have time to really look at them before, so that got us off pace.”
While most of the other manufacturers competing in the IMSA Weather SportsCar Championship already had experience with Michelins in the FIA World Endurance Championship, BMW was initially faced with a big challenge.
As Ferrari, Porsche, Ford and Corvette all headed to France to compete in the 24 Hours of Le Mans, BMW Team RLL underwent an extensive testing program in the U.S.
The M6 GTLM tested twice on the resurfaced Watkins Glen track in May, before heading to Road Atlanta for another fact-finding mission at the beginning of June.
“Since the last race we’ve had some testing and what we can see here this weekend is that we’ve been able to adjust the car to the new tires,” Marquardt said.
“I wouldn’t say we’re happy at the moment, but from our point of view it’s the step that we expected to make.”
Practice and qualifying showed that BMW is indeed on the pace again, with Dirk Werner putting the No. 25 BMW atop the time sheets on Friday and splitting the two Ford GTs on the grid for today’s six-hour race.
With Michelin offering GTE tires optimized for different engine configurations (front, mid and rear), while maintaining similar levels of performance across all cars, the mid-engined Fords and Ferraris were able to adapt quicker.
The larger, and heavier turbocharged BMW M6 GTLM, meanwhile, wasn’t necessarily initially suited to the rubber, but Marquardt believes that has now changed thanks to the continued development work.
“It looked like it affected us the most at Laguna Seca,” he said. “Porsche and Corvette didn’t seem to struggle as much as us there, but somehow we managed to catch up on that.”
Marquardt also pointed out that the Balance of Performance does not cover the effects a new tire can have on a car.
“I definitely like the way IMSA goes about its BoP,” he said. “It really is the best way, the scientific approach that was used before the season, measuring the cars properly, dyno testing the engines, WindShear [wind tunnel]…
“Le Mans didn’t look like much of a race [in GTE-Pro]. It’s a different BoP there anyway, so with regards to the championship here it’s different.”
BMW seeks its first win with the new M6 GTLM, in a class that has seen three different manufacturers claim victory in the opening four races this season.
John Dagys contributed to this report