Because my gsR gained 12hp@ the wheels from an ITR style manifold(sk2), 4 from the ITR thottle body, all with stock gsR cams, then i added ITR cams and gained another 14 over that.

all done @ coastal chassis dyno from a stock gsR to modded, and dyno'd after each mod



i mean if you cant afford to do it all, you have to do it piece by piece, but factory cams still have a little left in them to add a few parts to compliment the motor