The after-cat exhaust we chose for the Bullitt is Flowmaster’s Force II kit (PN 17267; $529.99). This kit is designed for ’99-’04 Mustang GT, Mach 1, and Bullitt models with a 4.6 engine. It’s a 21⁄2-inch system featuring Super 50 Series mufflers; mandrel-bent, 16-gauge, aluminized tubing; and 3-inch tips. This Force II kit is designed to provide a mild interior and exterior exhaust tone. Think of the Super 50 Series muffler like Flowmaster’s three-chamber offering from days gone by. Yeah, we know—we’re getting old.