3 1/2" Exhaust

The camshafts,stroker cranks,and aluminum heads,have outprogressed budget mufflers. It's that simple. A pair of 29.99 apiece turbo mufflers will get you to 450 ish. h.p. Done the "X" thing.., not my preference.Simply, spend big money on big parts,don't skimp on intake/exhausts systems.