What makes GTS mufflers different from the stock mufflers? Can the chambers in the stock mufflers be altered to give the GTS flow and sound characteristics?
Original Post
Two differences: first, the inlet of the std muffler has a small diameter pipe with three or four layers of tubing filling up space around it. These can be cut away and a larger dia. pipe substituted, if you've got time & no money, and are a decent welder. Second- the inside of both outlets are perforated metal so the gasses must make a turn then go thru a series of small holes. At the inner end is the "final" baffle- a 1" washer! It is tack-welded to the perforated tube and often breaks off, producing a 'jingle' noise at idle. Years ago, to gain power, guys used to jam a rod down the outlets and hit it with a hammer, which broke the washer off & freed up the flow. You gotta cut open the case and retrieve the washers or the jingle-jangle will eventually drive you nuts in traffic... Take a close look at my home-made "GTS" mufflers at 'Vegas next month.