Performance You'll Love. While the stock exhaust system might be enough for some, you can make your Pony sound more aggressive and deep while performing better using these Borla Over-Axle Pipes. When combined with the Borla Rear Section and X-Pipe (both sold separately), these Over Axle Pipes finish off the cat-back system. There's absolutely no drone at any speed, no matter the gear you're in. You'll love these pipes and your passengers will be impressed with how they sound. Built to Last. These Over Axle Pipes are designed to directly replace the factory ones and are made of high-quality mandrel-bent stainless steel. That means you don't need to worry about them warping or becoming corroded as they can withstand the rigors of everyday use. Excellent Quality. Borla has built up a serious reputation for making some of the finest exhaust systems in the industry. You can place your confidence in these Over Axle Pipes because they add solid value to your S197 Pony. Their diameter measures 2.75 inches, allowing exhaust to flow freely and your engine to breathe as it should. Borla uses custom tuning to ensure these pipes work great with your specific GT or GT500 Mustang. Application. Borla engineered these Over-Axle Pipes to work with all 2011-2014 Ford GT and GT500 Mustangs when combined with the Borla Rear Section Kit and X-Pipe to form a complete cat-back system.