[RET_COP]

I run 3" cobra packs from Classic Chambered Exhaust. They are louvered inside but the louvers are small compared to the old exhaust I had. I have no idea what was on there. I measured the ID before I welded them up and If I remember right they measured just under 3" ID. Night and day compared to the last set I had although those were 2 1/2 and not a true 2 1/2. I don't believe I have much restriction at all. I had to re-jet my carb ^^. Compared to auger I can't give you a caparison, RareIron has that information.