Well i already had a guy in mine to do all the work so i was gonna do a cat back system however we were trying to decide what muffler to use...my buddy has a glasspack on his explorer (4.6 v6) and the VX is louder stock so i kinda figured it wouldnt make the VX much louder. If anyone has tried a glasspack let me know if not i may just bolt one up just to hear the sound and let you guys know. I would rather have a decent muffler and substitute sound so i kinda think glasspack would be out, but i do want to go as loud as possible without sacrificing reliability. If anybody has a clip of a vx idling with a PV that would be helpful....Cyrk if you could get that clip up it would be nice maybe then i may not have to do the full system myself. Thanks!!