Excuse My Dust (1951)

Joe, an inventor in an American small town of 1895 has problems with his new invention, a car driven with a gasoline motor. Everybody is making fun about his "crazy invention", and only his girlfriend believes in him. When he's halfway successful, another woman tries to win his heart, and his girlfriend thinks he has quit on her. But in a race for those new horse-less vehicles, he gets in trouble and only his former girlfriend is able to help him.