Where can I find Flowmaster American Thunder Cat Back for a 04 mach 1. ALso anybody got any videos of this setup with stock h pipe.

 

i went to a local exhaust shop here in oklahoma city and paid less than $200 to have my 40 series flowmasters welded in....no point in replacing the whole cat back...especially if all you want is the muffler!! check your local shops!! then you wont have to worry about placing an order....waiting for your order to arrive/get shipped...ect, you can get r done right then and there!!

 

There is a point, you gain 2.5" mandrel bent piping....which is the only reason the exhaust adds any HP.

 

but then for that to have any effect wouldnt you also need a mid-pipe? i thought the gain came from replacing the stock muffler with the flowmaster for better flow.... shows how much i know =]~