S4 Cat-Back Exhaust System

Since 1989, Billy Boat has been designing, testing and producing quality exhaust systems for your vehicle. These systems improve air flow, giving you more power, while at the same time giving you an incredibly racy sound.

Billy Boat's catback system is a complete stainless steel mandrel bent cat-back exhaust. The exhaust is a dual 2.25" system that begins at the factory downpipes and continues to an innovative center muffler. The exhaust then splits and each mandrel bent pipes goes to its own muffler with a dual 3" (75mm) bevel-cut round tip.

This exhaust is very quiet and simply changes the tone of the exhaust to a deep unobtrusive sound. With TIG welding fully stainless construction and CNC'd hangers you will not find a higher quality system on the market.

All BB exhausts come with a full lifetime warranty.

Now that you have a new exhaust system, why not improve your air flow elsewhere? Cold Air Intakes are a great way to add some extra power to your vehicle. Check under the Engine section for all your performance part needs.