I know i saw a link before on this forum for comparison of cat-back exhaust with the dyno results (including Buscher's exhaust which made 2nd most power i think)

can anyone help me find that link, i did a search several times with no luck

 

You mean this one?: http://www.tprmag.com/issue/5/5_turbo_exhausts.shtml

 

thanks that's the one i was looking for