Why would you not consider a tune?.... 500 bucks for 20 Hp gain on a 28 is the best for your buck. I suggest going to the NA engine threads and do some reading. I personally have a 51 and before I knew that I believed I had a n52 and I was going to do a 3 stage swap which you should consider. But assuming you're looking for performance mods I recommend headers, PI and PE, and a tune.
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