gain for a 350Z with the intake and exhaust together was only about 8hp. This was in a national magazine. I was at the grocery store wasting time, so I dont remember which one, sorry...look it up next time you buy milk & cookies. Point is, how can such minimal gains beat a car with about 100hp advantage over it (assuming 400hp stage 3 vs 300hp 350) ? Both are about the same weight and both average about 5.4 sec. 0-60 stock?