I have used a Macs tunes pipe header, I cut 3/4" of the header off..J-B welded the 3/4"piece onto the bottom of the moouse can, and put a 1/4"ID X2" aluminum tube on the top of the can. I used a silicone cuppler to join the 2 of em and used a pipe hanger to support the can. I dont know that it was effective for any HP increase, but it was a functional muffler.