(93 Ex Coupe D16Z6)
i don't have a header but my cai and exhaust helped out UNBELIEVABLY the stock system was WAY too restrictive.
I have the iceman cai. when it's in it's short ram configuration it's better than stock... when it's sitting in the bumper IT"S REDICULOUS how much of a difference it makes (even compared to it as a short ram) the exhaust isn't a HUGE difference but it does make a difference. as far as a header is concerened yes if your getting a turbo later you might as well open your windows at 100 with the cash sitting on the passenger seat. but if your not going to do turbo then it's worth it with a cat. other wise you create an air volume incompatability between what the aftermarket header will try to let out and what the cat will let it put in it. this in effect causes a hiccup in the exhaust gasses.
I'm not sure if it's the kind of exhaust you get but everytime i drive by another honda they hit the gas like they're in a v8 and it sounds like shit (way to open) it sounds like a 90 year old angry smoker vomiting or something. my car has a rather nice growl. don't get me wrong with the cai in place and im in vtec my exhaust is nothing short of (REALLY LOUD).
as far as the original question best bang for the buck
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