OAO Valved Cat-Back Exhaust System for Audi B9 S4 / S5 3.0T V6 Turbocharged EA839 T304 Stainless Steel Performance Exhaust

Elevate the Audi S-Performance Experience

Designed specifically for the Audi B9 S4 and S5 equipped with the 3.0L EA839 turbocharged V6 engine, the OAO Valved Cat-Back Exhaust System is engineered to enhance exhaust flow, refine sound character, and unlock the full performance personality of Audi’s S-series platform.

By optimizing exhaust gas routing and reducing restriction in the rear section, this system delivers a deeper, more dynamic, and more engaging exhaust note while maintaining everyday comfort and refinement.

Constructed from premium T304 stainless steel and precision TIG welded throughout, the OAO exhaust system ensures long-term durability, corrosion resistance, and OEM-level fitment.

Key Features

✓ Designed for Audi B9 S4 / S5

✓ 3.0L EA839 Turbocharged V6 Platform

✓ Premium T304 Stainless Steel Construction

✓ Electronic Valved Cat-Back Exhaust System

✓ High-Flow Performance Design

✓ Precision TIG Welded

✓ Mandrel-Bent Tubing Structure

✓ Improved Exhaust Flow Efficiency

✓ Reduced Exhaust Backpressure

✓ Enhanced Turbocharged V6 Sound Character

✓ Lightweight Performance Construction

✓ OEM-Level Fitment

Intelligent Valve Control System

Comfort Mode

With the valves closed, the system maintains a refined and subtle exhaust tone suitable for daily driving.

Ideal for:

• Daily Commuting

• Highway Cruising

• Urban Driving

• Passenger Comfort

• Low-Noise Environments

Dynamic / Sport Mode

Open the valves and unleash the full character of the EA839 V6 turbocharged engine.

Benefits include:

• Louder Exhaust Output

• Deeper V6 Turbo Sound

• Enhanced Engine Presence

• Sharper Acceleration Tone

• More Aggressive Overrun Character

• Increased Driving Engagement

Performance Benefits

The OAO Cat-Back Exhaust System is designed to improve exhaust efficiency and enhance driving dynamics without compromising refinement.

Potential benefits may include:

• Improved Exhaust Flow

• Reduced Backpressure

• Sharper Throttle Response

• Enhanced Turbo Spool Character

• Improved Engine Responsiveness

• More Engaging Driving Feel

Actual performance gains may vary depending on ECU tuning and supporting modifications.

Sound Characteristics

The OAO B9 S4/S5 exhaust system is tuned to enhance the refined yet sporty character of Audi’s EA839 platform.

Drivers may experience:

• Deep Refined Idle Tone

• Strong Mid-Range Turbo Presence

• Enhanced V6 Character

• Aggressive High-RPM Sound

• Smooth Yet Sporty Exhaust Balance

• Improved Sound Clarity Over Stock

Designed to transform the factory-exhaust experience into a more emotional and dynamic driving soundtrack.

Premium T304 Stainless Steel Construction

Manufactured from high-grade T304 stainless steel for maximum durability and long-term performance.

Advantages include:

• Excellent Corrosion Resistance

• Superior Heat Resistance

• Long Service Life

• High Structural Strength

• Motorsport-Grade Engineering

Each system is precision TIG welded and individually inspected before shipment.

Vehicle Fitment

Compatible with:

• Audi S4 B9 (2017–2024)

• Audi S5 B9 Coupe / Sportback (2017–2024)

Engine Platform

• 3.0L EA839 Turbocharged V6

Model Years

• 2017

• 2018

• 2019

• 2020

• 2021

• 2022

• 2023

• 2024+

Please verify your vehicle specifications and exhaust configuration before ordering.

Package Includes

• OAO Valved Cat-Back Exhaust System

• Electronic Valve Control Module

• Remote Controllers

• Installation Hardware Kit

• Protective Packaging

Installation

Direct bolt-on design utilizing factory mounting points.

Professional installation is strongly recommended to ensure optimal fitment and performance.

Important Notes

Please check local emissions regulations before installation.

This product is intended for off-road or motorsport use where permitted by law.

Why Choose OAO Performance

OAO specializes in premium performance exhaust systems for Audi RS/S models, BMW M, Mercedes-AMG, Porsche, Ferrari, Lamborghini, and other high-performance platforms.

From valved cat-back systems and downpipes to titanium exhaust solutions, every OAO product is engineered to deliver precision fitment, durability, and a truly engaging driving experience.

Upgrade your Audi B9 S4 / S5 with sharper response, improved exhaust flow, and the refined performance character of OAO Performance.