I don't want to sound like a prick, but basically any exhaust you put on a cavalier will make it sound like a.....cavalier. At it's best it'll have an annoying high pitched buzzing tone that'll shatter the ears of all those you pass by.
-although-
you could make it have a deeper tone and not that horrible raspy noise if you stay away from any exhaust that ends with a resonated tip. Basically if you put in a high flow catalytic converter, got mandrel bent exhaust with slightly larger piping (bent smooth without the dimples) and a high flow muffler (like a flowmaster among others) with a regular pipe coming out (doesn't enlarge at the end), you may be able to get away with it having a deep exhaust note like a forklift does (forklifts around my work don't sound too bad for 4 cylinders). But for the love of god, stay away from ANYTHING labeled SPORT COMPACT. Another thing to give it a deep tone when you step on it that's quiet when you let off is some sort of tubular intake hose with a high flow air filter like a K&N, or just a conical air filter at the end of the intake tube would give it a deep sound when you gave it gas. Good luck!
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'84 Mustang 5.0 LX
My car