Drivers and their classic cars from the Formula D group, above, negotiate a turn on the Pacific Raceways’ road course during the 31st annual Pacific Northwest Historics (PNWH) vintage auto races under overcast skies Sunday in Kent.

The field includes hundreds of the world’s rarest and most pristine pre-1985 race cars, many of which tested the 10-turn, 2.25-mile road course.

Pacific Northwest Historics Vintage Racing Charities and the Society of Vintage Racing Enthusiasts (SOVREN) presented the three-day race, a benefit for Seattle Children’s, with the majority of the proceeds supporting uncompensated care at the hospital.

The weekend paid special tribute to the 50th anniversary of IMSA racing.

“One way people describe it is ‘we’re not just collecting art, we’re racing it,’ because these cars are art,” said Martin Rudow, a former racer, president of the PNWH and past president of SOVREN. “They’re beautiful pieces of machinery, and much more so now than then.”

Fan-favorite marques BMW, Mustangs, Camaros, Porsches, Alfa Romeos and Ferrari. Corvettes and Camaros gave chase.

Car owners and tuners came from throughout the Pacific Northwest, along the West Coast and Canada.