I'd guess late 70's, early 80's. I just remember the commercial... they something about the guy like "he was the guy with the fast car", then "she was the girl with the shimmy" and she says "I'm gonna shake it till I break it". Interested in part cuz I'm betting they went on to become famous after making this low budget drive in flick.
It sounds sort of like ALOHA, BOBBY AND ROSE (1975), but the tag lines you quoted don't quite fit.
(https://upload.wikimedia.org/wikipedia/en/1/1b/Film_Poster_for_Aloha%2C_Bobby_and_Rose.jpg)
Or it could be CORVETTE SUMMER (1978)
http://youtu.be/4W9pmT6JTO4 (http://youtu.be/4W9pmT6JTO4)
Or EAT MY DUST (1977)
http://youtu.be/05U2KaGlIC8 (http://youtu.be/05U2KaGlIC8)
or GRAND THEFT AUTO (1977)
http://youtu.be/Q1pPXOBHkbA (http://youtu.be/Q1pPXOBHkbA)
or JOYRIDE (1977)
http://youtu.be/-lpME21dy78 (http://youtu.be/-lpME21dy78)
Damn-there were sooo many of these types of movies back then! I could go on forever!
Bobbie Jo & The Outlaw?
All good choices bu I don't think that any are the right one. They are similar though, and from the right era. Anyone have any other ideas?