I got a pair of cherry bomb glasspacks from autozone for like 20 bucks a piece. Basically the same thing, you can get them in all sorts of different lengths, from 12 inches to a bit over 30. The shorter the louder. I put 26's on mine and at idle it's about middle of the road for noise compared to the other 5.0's in the area, the tone is a bit more harsh and pissed compared to chambered.