I never played this game, I never had a C64 actually. But this makes me think of 'Stunts
', another game with cars and ramps which I had back in the 90's, can't remember exactly when... Well, this game was fun too, it was in 3D (read 320x200 16colors with no texture or shading or whatnot) and you could build your own tracks... Some guys
recently 'remade' it and it looks pretty cool. It's called Crashday
and should be released this year.