Burn 'Em Up O'Connor (1939)

Racing-car enthusiast Jerry O'Connor and his dim-witted mechanic Buddy Buttle get their chance to join the crew of race-car builder Pinky Delano, who just suffered a setback when one of his drivers was killed by failing to make a turn on the track. Then, one by one, his other drivers suffer the same fate, until it is Jerry's turn to drive in the big race. Buddy tries an experiment and determines these were no accidents, but is it too late to help Jerry, who has started the race?