Bill Auberlen and Dillon Machavern mastered tricky wet conditions to win round seven of the IMSA Michelin Pilot Challenge season at Road America for Turner Motorsport.
The BMW pair took their second victory in three races after a tense run to the line for Auberlen, who drove the last 76 minutes of the two-hour race on the same tank of fuel amid progressively heavier rainfall and diminishing visibility around the four-mile circuit.
Winward Racing’s Mercedes-AMG GT4s finished second and third, with Alec Udell and Bryce Ward coming through 15.7 seconds behind the winning No. 95 BMW M4 GT4.
Turner and Winward filled out the top four places, as Indy Dontje and Russell Ward completed the podium in their AMG ahead of Robby Foley and Vin Barletta’s BMW entry.
Machavern and Foley built up a large lead after breaking away from an early three-way battle with the fellow Watkins Glen-winning Notlad Racing by RS1 Aston Martin Vantage GT4 and the No. 4 Winward Mercedes of Dontje and Ward.
Machavern started from pole position and held his place through the opening laps despite pressure from Patrick Gallagher in the Aston and Ward, who rolled off in fourth.
Gallagher grabbed the lead after 19 minutes when Machavern went out of shape exiting the Carousel, but the Notlad driver was unable to open a gap to the two cars behind.
The first, and in some cases only, pit stops for the GS field took place just before a Full Course Yellow which appeared after 45 minutes due to Ryan Hardwick’s Wright Motorsports Porsche stopping in a compromised position with an electrical issue.
Winward took the lead during the pit cycle — during which the leaders continued on wet Michelin tires — as Dontje emerged ahead of Auberlen, Stevan McAleer in the Aston Martin and Udell in the other Winward car which qualified down in ninth.
However, Dontje appeared to struggle for pace in the early stages of his stint, with Auberlen easily passing the Dutchman into Turn 1 at the restart with just over an hour remaining. McAleer also went through at Turn 2, restoring the order from the first laps.
Auberlen increased the gap over McAleer to 10 seconds in half an hour, shortly after which the Notlad Racing driver was forced to pit off-schedule with a left-rear puncture.
Just before McAleer exited the lead battle, the Winward Racing Mercedes-AMGs had slipped to fifth and sixth behind Spencer Pigot’s MIA McLaren 570S GT4 and Trent Hindman in the Archangel-prepared VOLT Racing Porsche 718 Cayman GT4 Clubsport.
Another car to hustle the curiously off-pace Winward machines was the No. 21 Riley Motorsports Toyota GR Supra GT4, however Scott Andrews was forced to retire the car after picking up steering damage due to side-on contact with Dontje at Canada Corner.
Dontje and Udell’s initial lack of pace in the second stint went on to prove beneficial in the long run, as Pigot and Hindman both pitted for fuel top-ups with 10 minutes to go, releasing the Winward pair into second and third.
Winward’s riskier single-stop strategy paid dividends to an extent, although the Texan team’s hopes of snatching a one-two were extinguished when Auberlen managed to guide his Turner BMW to the end without needing a fuel splash.
Evidence of the strict fuel-saving required was provided by PF Racing’s fifth-placed Ford Mustang GT4, which stopped at the base of the hill leading up to the checkered flag.
Michael McCann and Andrew Davis consequently picked up a top-five result in their McCann Racing Audi R8 LMS GT4, while Pigot and Sheena Monk settled for sixth after their McLaren’s late stop.
Eric Foss and Jeff Mosing placed seventh in the No. 56 Murillo Racing Mercedes-AMG which also made two pit visits. Hindman and Alan Brynjolfsson’s Porsche was eighth.
Black Dog Speed Shop’s McLaren and the other Murillo Mercedes completed the top ten.
KMW Scores Alfa’s Maiden TCR Victory
Roy Block and Tim Lewis Jr claimed a landmark TCR win for KMW Motorsports with TMR Engineering, which became the first Alfa Romeo team to triumph in the class.
Block started fourth on the grid but dropped a handful of places, only for KMW to vault into the lead by pitting just before the second FCY intervention. The first short FCY of the day occurred in the opening minutes of the race after a spin for one of the GS Audis.
Lewis led the restart from Ryan Eversley, who would later make an extra stop to switch back to wet tires after gambling on slicks for the second stint.
The Alfa Romeo driver kept ahead of a charging Parker Chase in the No. 98 Bryan Herta Autosport Hyundai Elantra N TCR for around half an hour, until the positions switched coming out of the Carousel.
Chase looked set to deliver his and Ryan Norman’s second win of the year in the car that led the opening stages of Saturday’s encounter, only for the 20-year-old to leave the track coming out of Turn 2 with 17 minutes left on the clock.
That excursion through the grass saw Chase slip back to fourth, and handed the lead back to Lewis who tamed the increasingly wet conditions to take his and Block’s first win of the campaign after they finished second last time out at Lime Rock Park.
Denis Dupont and Rory van der Steur took their best result of 2021 with the No. 19 Hyundai Veloster N TCR in second, while Chase and Norman ended up third.
RESULTS: Road America 120