Introducing the APR Catback Exhaust System for the Audi B9 RS4 and RS5, part number CBK0037. This exhaust system is not just a performance upgrade; it's a complete transformation for your vehicle, designed to deliver an exhilarating driving experience. Crafted with precision engineering, the APR Catback Exhaust System runs the entire length from the catalyst back, ensuring you get the most out of your engine's capabilities.

One of the standout features of the CBK0037 is its remarkable sound profile. Expect a bold, aggressive growl when you hit the throttle, paired with an impressive gain of 9 horsepower and 15 FT-LBS of torque to all four wheels. Customers rave about the sound, with one enthusiast noting, "The growl is just perfect—loud when you want it, but not obnoxious during daily drives."

Constructed from T304 stainless steel with a brushed finish, the system is built to withstand harsh conditions while maintaining its striking appearance. The dual 2.75" downpipes and a massive 3.5" midpipe ensure optimized flow, while the integrated Helmholtz resonator minimizes drone, allowing for a smooth driving experience. Another customer mentioned, "I was worried about drone, but this system is spot on—just the right amount of noise."

Installation is straightforward thanks to precision-fit brackets and OEM-style slip clamps. The upgraded tunnel brace included with the system accommodates the oversized piping, making it easy for enthusiasts to upgrade without hassle. "The fit was perfect, and I had it installed in no time," shared a satisfied buyer.

Visually, the exhaust system features RS-style diamond black oval tips that measure 7.25"x5", adding a sleek touch to your vehicle's rear. The subtle APR logo on the tips provides a refined finish that complements the overall aesthetic of your Audi.

The APR Catback Exhaust System is designed for those who seek the perfect balance of power, sound, and style. With its durable construction and performance-driven design, it promises to enhance your driving experience for years to come.

• Complete catalyst-back system including downpipes, extending from the factory catalyst back.
• Performance gains of 9 HP and 15 FT-LBS of torque delivered to all four wheels.
• Premium T304 stainless steel construction with TIG welding for strength and durability.
• Optimized flow through dual 2.75" downpipes, 3.5" midpipe, and quad 2.5" exits.
• Mandrel-bent brushed piping paired with electropolished cast splitters for a refined finish.
• Precision brackets and slip clamps ensure accurate alignment and hassle-free installation.
• Includes an upgraded tunnel brace to accommodate the larger piping.
• Integrated Helmholtz resonator minimizes drone and enhances sound quality.
• Valve-controlled rear mufflers dynamically adjust sound based on driving style.
• Dual 7.25"x5" RS-style diamond black oval tips with APR logo.
• Smooth transitions and straight-through components maximize performance by reducing restrictions.
• Strikes the perfect balance of power, sound, style, and quality for enthusiasts.
• Fully emissions compliant for worry-free operation.

• Bending: Mandrel
• Brackets: Precise
• Brand: APR
• Category: Exhaust
• Clamp Style: Slip Clamp
• Clamps Included: Yes
• Emission Code: 5
• Exit Tube Diameter: 2.5"
• Material: T304 Stainless Steel
• Muffler Finish: Brushed
• Muffler Style: Sound Absorption, Helmholtz
• Product Type: Exhaust Catback System
• Sub Category: Exhaust and Tail Pipes
• Tip Count: 2
• Tip Diameter: 7.25"x5"
• Tip Style: RS-Style Oval
• Tube Connection: Butt Joint
• Tube Diameter: 3.5"
• Tube Diameter: 2.75"
• Tube Diameter: 3"
• Tube Finish: Brushed
• Valve Actuation: OEM
• Valves: Yes
• Welding: TIG