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Exhaust› Exhaust Pipes, Systems and Components
APR Tuning
B9 RS5 CAT-BACK KIT
SKU: A0CU CBK0037
Moderate — 2–4 hours
Overview
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Part #: CBK0037
Introducing the APR Catback Exhaust System for the Audi B9 RS4 and RS5
Features:
- 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.
Fits Audi RS4 18-25, RS5 18-25
Product descriptions are provided by our supplier partners and may not always be perfectly accurate. Not sure this fits? or call (760) 282-4645 and we’ll verify before you order.
Fitment
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Specifications
| Brand | APR Tuning |
| Part Number | A0CU CBK0037 |
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