I have an 85 GT with bone stock exhaust...I want to go with Mac full length 1 5/8 headers Mac off road h-pipe no cats...and the full cat back system....1st how will it sound...will it be loud...right now its so quiet....and how much HP will the system give me...My plan after that will to bolt on an B&M 144 blower making 6 psi....im hoping to get into the low 13's high 12's i hope what do you think?