Originally Posted by Dale B

A spoiler on the rear of a front-wheel drive car that provides downforce on the rear of the car at speed is a pretty bad idea. That's because that would create less force downward on the drive wheels, where it is needed for performance driving. So feel free to laugh at all the big spoilers on FWD cars that are pretending to be there for extra performance. The majority of them are just there for looks, of course. The owners, however, generally don't know that, in theory at least, they have made things worse, not better. (Although tigerhonaker is also correct that at normal driving speeds, there is very little downforce effect).


In theory, the design of the lip spoiler on the HAH trunk improves aerodynamics by a slight amount, as others have said.