Originally Posted by 90civic_Si
depending on if all the stuff that you are putting on is NAME BRAND LIKE AEM DC SPORTS GREDDY.. all that good stuff.. then prolly about a good 30 to 40 hp.... when i added my headers.. resinator w/2.25 piping. and n1 apexi muffler / AEM CAI i added about 45 hp..... but it all depends on the way and how you do it with what kinda sutff.. ya know/
Basic bolt-ons on an otherwise stock motor will not give you 45 hp gains even if they are the best quality out there. You would be lucky to pick up 10hp from those mods.