Audi RS4 B9 Downpipes – Catted & Decat Performance Exhaust Upgrades

Audi RS4 B9 Downpipes – Unlock the True Potential of the 2.9 TFSI

The Audi RS4 B9, produced from 2017 onwards, is powered by the cutting-edge 2.9 TFSI twin-turbo V6 engine delivering outstanding performance. While the stock RS4 B9 is already fast, the restrictive OEM downpipes limit exhaust flow and overall power. Upgrading to performance Audi RS4 B9 downpipes is one of the most effective ways to increase horsepower, improve throttle response and unleash an aggressive exhaust tone.

Why Upgrade to a Performance Audi RS4 B9 Downpipe?

The factory downpipes are designed to meet emissions and noise regulations, but this comes at the cost of restricted performance. Replacing them with high-flow RS4 B9 downpipes provides multiple benefits:

• Increased horsepower & torque – reduce backpressure and improve exhaust gas flow.
• Faster turbo spool – less restriction means quicker boost response and sharper acceleration.
• Enhanced exhaust sound – catted downpipes offer a refined, sporty note, while decat downpipes unleash an aggressive, motorsport-inspired roar.
• Lower exhaust gas temperatures – improved thermal efficiency protects the turbo under high load.
• Perfect for ECU tuning – essential for Stage 1, Stage 2 and hybrid turbo builds.

Types of Audi RS4 B9 Downpipes

Our range of Audi RS4 B9 downpipes is designed to suit different performance goals and tuning stages:

Catted Audi RS4 B9 Downpipes

Catted downpipes include a high-flow sports catalytic converter, providing an excellent balance between emissions compliance and performance gains. Ideal for street-driven RS4 B9 models in regions with strict regulations.

Decat Audi RS4 B9 Downpipes

Decat downpipes remove the catalytic converter entirely, maximizing exhaust flow and power output. Best suited for track-focused builds and off-road performance applications.

Material Options: Stainless Steel & Titanium

The construction material significantly affects performance, weight and heat resistance:

• Stainless steel downpipes – durable, cost-effective and corrosion-resistant, perfect for most performance builds.
• Titanium downpipes – ultra-lightweight, superior heat dissipation and a premium motorsport finish.

Performance Gains with Audi RS4 B9 Downpipes

Installing performance RS4 B9 downpipes offers substantial performance improvements, especially when combined with ECU tuning:

• +25–40 HP with downpipes alone.
• +50–85 HP when paired with Stage 2 remapping.
• Significant torque gains for stronger mid-range acceleration.
• Sharper throttle response and improved turbo efficiency.

Choosing the Right Diameter

Downpipe diameter plays a key role in optimizing performance:

• 3-inch downpipes – ideal for Stage 1 and Stage 2 setups.
• 3.5-inch downpipes – designed for hybrid turbos, big turbo conversions and extreme power builds.

All Audi RS4 B9 downpipes are designed for direct bolt-on installation, ensuring perfect fitment without modifications.

Build Quality & Engineering

Our performance Audi RS4 B9 downpipes are engineered using motorsport-grade materials and precision manufacturing:

• Mandrel-bent tubing ensures smooth, unrestricted exhaust flow.
• Precision TIG welding for maximum strength and durability.
• OEM-style flanges and fittings for seamless installation.
• High-quality gaskets and mounting hardware included.

Tuning Potential

Pairing your RS4 B9 downpipes with ECU tuning unlocks the full potential of the 2.9 TFSI twin-turbo V6 engine:

• Optimized fueling and boost strategies for maximum gains.
• Customizable exhaust sound profiles depending on catted or decat setup.
• Supports advanced builds, including ethanol (E85) tuning, hybrid turbos and big turbo conversions.

Recommended Upgrades

For best results, combine your Audi RS4 B9 downpipes with other supporting performance upgrades:

• Turbo gaskets
• Mounting flanges
• Blow-off valves
• Performance intercoolers
• ECU tuning solutions

Conclusion

Upgrading to performance Audi RS4 B9 downpipes is one of the most effective modifications to improve power, turbo spool and exhaust sound. Whether you choose catted or decat downpipes, our selection guarantees premium quality, precise fitment and proven performance gains. Take your RS4 B9 to the next level today.