i have a muffler delete exhaust already with stock h pipe if i install the o/r x pipe on with stock manifold would i lose to much back pressure? a guy in my unit says the mustangs need some back pressure or u loose hp from too much free flow...
about me...this is my 3rd mustang all have been s197 i started with the 08 v6 traded it in for 05 gt auto then traded it in for 05 roush stage one manual... so far i have done the basics... i have installed the steeda cold air and sct 93 bama tune i noticed a pretty good difference not sure if...
