originally I had the voodoo brand I think of banana tube expansion chamber that came w/ the kit I ordered (IIRC i talked the guy into throwing it in cuz I got a aluminium gt frame kit plus a relatively premium engine kit at the same time) but I had problems w/ it not quite fitting, then when i bent it around the frame for a proper fit I was a bit careless & cracked it & didn't mount it quite well enough.... it actually sheared right off where it curves around the frame & left me w/ about 6in straight pipe. straight pipe ==> runs like crap, maybe 1/2 power, plus it sounds like an F'ing ammo dump burning down I bought a cheap stock exhaust used on some MB's from a friend for $10, but it's so restrictive at the end that power's no better than the straight pipe (though noise sure is). It's pictured in the attachment anyway, long story short, I took matters into my own hands & made this somewhat frightful expansion chamber exhaust. I made the main chamber part by cutting out the inside of a can of spray paint, putting it over the broken straight pipe, & bending it into the geometry I wanted as best I could. it's held in place w/ some wire & cable; a few layers of foil & muffler repair cold weld adhesive putty; and a little duct tape & hi temp engine paint. Also, there's a second aluminum bottle cut open & nestled on over the expansion chamber (steel paint can)'s outlet, w/ a tiny bit of foil & steel wool for sound dampening in the between space I didn't really expect it to work, but now that I sealed the leaks it's giving me better performance than the often $70+ (or unavailable out of stock) voodoo expansion chamber I had originally had. power seems boosted in mid range & higher engine speed conveniently, there's a radar speed camera on a challenging uphill by my house, so I can charge the hill & use it to gauge power output. results have been: badly out of tune, or >50% choke -- won't make it up. voodoo banana expansion chamber exhaust -- 24mph Straight pipe -- 17mph (& lucky not to be arrested for disturbing the peace!) Stock lo end replacement exhaust -- 18mph Murphy McMonkeyPatcher kludge pictured below - 26mph!! Clearly, the right way to do exhaust modding involves learning to weld. but I'm finding it possible to get surprisingly acceptable results w/out access to welding equipment. Any thoughts, tips or experiences you'd wanna share on this?