Which combination of Intake/Y-pipe/Cat/Catback would result to the greatest power gain for a N/A 4th gen. can you also give a ballpark price of everything too.

 

Y-pip and Cat-back is the best combo, CAT is a wast of money, just punch it out! lol, hm....
the exhaust system on the 4th gen is very restrictive, 2pre-cat on the y-pip, CAT, another silence before the muffler.

OH! here is the preious owner of my car(Andi), he dynoed with just Y-pip and Pop charger.
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