Winfield was not the driver in the race. Though he tried to qualify (he was the team's mechanic), he spun the car. The Novi V8 was built to Winfield's design by Winfield and Leo Goosen at Fred Offenhauser's shop, in the old Miller plant the latter had bought.
It's possible the puzzle photo was taken at Bonneville. After the 1947 Indy 500, Mobil sponsored the car in some record runs there, where it turned some circular laps. On August 21 1947, Marv Jenkins (Ab Jenkins' son) took to the circle track twice, the first time out he averaged 183.6 mph and the second run was 175.4. Note the missing "Governor" livery, which the cars featured at Indy.
Judging by the hood bumps, the puzzle car is the Cliff Bergere car that DNF'd at Indy with a burned piston.