Heathcliff and the Catillac Cats

The cats put a new engine into the Catillac not realizing it is a time machine engine of Professor Craziloon. Before they know it they're back in the old West. After a few close calls with some rough and tough characters and a wild stagecoach chase in pursuit of their stolen caddy, they get the car back in the nick of time to be transported back to the future.