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Exhaust› Exhaust Pipes, Systems and Components
APR Tuning
Catback Exhaust System S4 / S5 (B9) Fits Audi S4 18-25, S5 18-25 APR
SKU: A0CU CBK0012
Moderate — 2–4 hours
Overview
Show original supplier description
Part #: CBK0012
Introducing the APR Catback Exhaust System for the Audi B9 S4 and S5
Features:
- Complete catalyst-back system including downpipes, extending from the factory catalyst back.
- Performance gains of 10 HP and 12 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 2.5" downpipes, 2.75" midpipes, and a 3.5" midpipe.
- 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.
- Removable quad 3.5" motorsport-style polished tips with APR logo; optional styles available.
- 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 S4 18-25, S5 18-25
Vehicle Symptoms
- Exhaust note too tame and quiet
- Restrictive stock exhaust limiting power
- Drone on the highway at cruising speed
- Want a more aggressive, sporty sound
- Exhaust system feels heavy
Relevant Conversations
- APR catback exhaust B9 S4 review
- Best catback exhaust for Audi S4 B9
- APR vs AWE catback B9 S5 comparison
- How to install APR catback on B9 S4
- APR catback exhaust sound clips
- B9 S4 exhaust drone fix
- Improve exhaust sound Audi S4
- Catback exhaust gains for stage 2 tune
- APR catback vs stock weight
- Where to buy APR catback exhaust
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 CBK0012 |
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