Reduced backpressure gives your BMW an instant horsepower boost! The stock BMW muffler has a vacuum-activated butterfly valve on the driver's side muffler. This valve is closed under most conditions, diverting all exhaust gases to the passenger's side. Under certain conditions (e.g. high throttle/low vacuum), the butterfly valve opens so two mufflers can be used. The Sport version of our Tri Flo exhaust eliminates the actuator and butterfly valve so both exhausts are used all the time. The result is an increase in horsepower and a more aggressive sound that announces your performance upgrade to anyone within earshot. (For a more refined growl, consider the Touring version of this exhaust, which uses a vacuum-activated valve just like the stock exhaust.) Stainless steel construction. Limited lifetime warranty. Simple Cut/Clamp installation. Includes left and right mufflers.
Since 1989, Billy Boat Performance Exhaust systems have incorporated 3-generations of fabrication skill and racing talent inherited from the Boat Family. B&B starts with T-304 stainless steel known throughout the industry as the highest quality material practical for automotive exhaust applications. All exhaust tubing is mandrel bent on sophisticated CNC machinery for precise fit and uninterrupted exhaust flow. What's more, the use of T-304 stainless steel flanges offers precision fit and complete resistance to harsh elements. All hangers, resonators and tips are T-304 stainless steel as well. Every muffler is built in-house with years of racing and street development invested into its design. Each muffler is tuned to match its application for the best possible performance gain and sound quality combination. Stress relieved end plates, gussets and TIG welding ensures awesome strength and rugged durability.
Everything we sell comes with a minimum 12-month warranty and a 100% satisfaction guarantee. In addition, products that carry the Bavarian Autosport brand come with a minimum 2-year warranty against defects in materials and workmanship. (Some have lifetime warranties!) If you are unhappy with a product's quality or performance, simply let us know. We'll make it right. Call us at 800.535.2002 or e-mail [email protected].