Beach Party series feel to it. Plus a number of the same cast and crew. Including director/writer William Asher.
This time around, Frankie Avalon is a up-and-coming race car driver. After arriving in a new town and beating the local champ (Fabian), Avalon is offered a job trying out a new car for a upcoming cross-country race. Being gullible (and having the hots for the race tracks sexy owner, Julie Parrish), he agrees. Ends up the car is loaded with moonshine. Before long, Avalon is catching stress from all ends: he's being blackmailed by IRS agents, catching heat from the moonshiners, being a professional racer, knocking boots with Parrish, getting into multiple fistfights and he sings 5 songs! What a guy.
While F500 does have a "Beach" feel to it, the tone of the film is more adult. There's moonshine drinking, an on-screen death, endless references to sex, fighting, a guy catching on fire, implied stripping, a "beaver" reference, car wrecks, Parrish grabbing Avalon's butt cheeks, etc. I doubt most people would care for it at all, but I enjoyed FIREBALL 500 from beginning to end. The story is goofy, but it was a lot of fun watching Avalon trying to be serious. I also enjoyed all the familiar faces in the background. I didn't care too much for Fabian's hair though.
Recommended for fans of the Beach Party movies.