I hear the same exhaust sound every time i hear them pass by
cobb is a pretty popular one, but there are a lot of different ones. wrx explains the sound differences pretty well
probably some type of Borla exhaust system
There are a lot of different exhaust sytems available for the wrx/sti. All of them relatively sound the same because of the boxer engine and unequal length headers that the wrx and sti come with. The difference between exhaust systems is the power gains, style, and again a little difference in sound. All of these differences are very close and the difference in performance gains you get with different exhausts are minimal, and not necessarily noticeable.
