46mech,
Dump the stock muffler. You can get a 21471 @ NAPA. It should run you around $95. An alternative is a Dynomax 17225. It is a smaller 4" muffler of the same design. Becasue of it's smaller size, it will be a little louder, but I don't find it obnoxious by any means. You can get one from Summit for around $50.
-Ryan