Borla stainless steel S-Type rear section exhaust systems for the 2005 through 2009 Mustang 4.6L and 5.4L once again have proven why Borla has led the aftermarket performance exhaust industry for over 30 years. Borla has an exalted heritage with high performance vehicles, from the C5R LeMans winning Corvettes to privateers like KTEC, Ratt-Miller, Lingenfelter, and Lou Gigliotti, who have enhanced Borla's knowledge of both the vehicle dynamics and the power-plant engineering. Airflow management and exhaust engineering is a science with which Borla has more experience than anyone in the exhaust aftermarket. The "S-Type" is a smaller, round muffler with a center-in/center-out configuration, giving your Mustang a more aggressive sound and higher flow. Borla's free-flow Mustang exhaust systems utilize patented award and race-winning technology to deliver quality, sound, performance gains, and enhanced fuel economy--all with an easy bolt-on installation.