Okay, I wanna get either an off-road h-pipe or x-pipe, both are around the same price ($1XX). I heard that an h-pipe is louder than an x-pipe? So i was leaning that way. What kind of Torque and HP gains can i expect with each? What are common installation issues with each? Do i need MIL eliminators? I have an 1989 5.0. My current mods are just cold air intake and flowmasters out back. Thanks everyone