DuMaurier 7

I am looking for a catback for my car , I am looking for something with 3.5 or 4 " pipe with a large packed barrel that CAN actually do some quieting , I need it to quiet down my semi pp motor a bit . I am not expecting (or wanting ) it to be completely silenced , but my present 3.5" straight through , is a bit too loud (the exhaust berrel doesn't have any packing in it !!) , please pm me if you have what I'm looking for , thanks.