What is the song when they are both in the camper van driving?

It's been so long since I have seen that film and I can't recall what song it was. Here is a list of the songs on the sound track for it.

Stir Crazy (1980) - Soundtracks - IMDb (http://www.imdb.com/title/tt0081562/soundtrack?ref_=tt_trv_snd)

Thanks Odin, I have the soundtrack but this song is not on it which is strange. Anyway this is the song have no idea who sings it.
https://www.youtube.com/watch?v=mnpdtDDkU2o https://www.youtube.com/watch?v=mnpdtDDkU2o

A song like that could very well be just an instrumental that was made just for the movie.

Shame it's a good tune would like to buy it.