George Kurtz completed a clean sweep of the GT America powered by AWS weekend at Sonoma Raceway with a flag-to-flag victory in his DXDT Racing Mercedes-AMG GT3 Evo.
Kurtz overcame a late-race restart and challenge from Charlie Luck to take a 1.649-second win over the No. 45 Wright Motorsports Porsche 911 GT3 R.
Luck, meanwhile, claimed top class honors in the GT3 Masters division for drivers over the age of 55.
Jason Harward benefitted from late-race issues for the No. 191 Rearden Racing Lamborghini Huracan GT3 Evo of Jeff Burton to finish third overall.
Harward ran as high as second in the early stages before dropping to fourth until Burton slowed in the closing minutes with unidentified issues to his Lamborghini.
It also promoted Dmitry Novikov to a top-five finish in his No. 29 Rearden Racing Lamborghini, with Jason Daskalos rebounding to fourth in his Audi R8 LMS ultra.
Daskalos had an early coming together with one of the Lamborghinis early in the 40-minute contest.
Holland Takes First Win in GT4
Robb Holland claimed top class honors in GT4 in his Rotek Racing Ford Mustang GT4 for the first time.
Holland, who finished second in class on Saturday, finished 1.470 seconds ahead of the No. 11 Classic BMW M4 GT4 of Phil Bloom in second.
Race 1 class winner Sean Quinlan completed the class podium in third in his Stephen Cameron Racing BMW.
RESULTS: Race 2