If you’re an Audi enthusiast, you already know that the RS6 C8 is a masterpiece of performance engineering. Its 4.0-liter twin-turbo V8 delivers exhilarating power, but for those who crave even more, upgrading the downpipes is a game-changer. In this article, we’ll explore the difference between audi rs6 c8 downpipes catless and catted, how they affect performance, sound, and emissions, and which might be right for you.
What Are Downpipes and Why Upgrade Them?
A downpipe is a section of exhaust piping that connects the turbochargers to the rest of the exhaust system. In stock form, the RS6 C8’s downpipes are fitted with restrictive catalytic converters designed to reduce emissions but also limit exhaust flow.
Upgrading to performance downpipes—whether catless or catted—reduces backpressure, allowing exhaust gases to exit more quickly. This helps the turbos spool faster, increasing horsepower and torque while enhancing throttle response.
Catless vs. Catted: The Basics
When talking about audi rs6 c8 downpipes catless and catted, the key difference lies in the catalytic converter setup.
- Catless Downpipes
- These have no catalytic converters at all. The absence of restrictions means maximum exhaust flow, improved turbo efficiency, and the most aggressive sound possible. The car will have a raw, motorsport-like tone that’s hard to ignore.
- Catted Downpipes
- These retain a high-flow catalytic converter. While less restrictive than stock, they still filter exhaust gases to reduce harmful emissions. You’ll get a performance boost, a deeper exhaust note, and fewer issues with inspections or emissions compliance in certain regions.
Performance Gains
Upgrading to either option can yield noticeable performance improvements.
- Catless Downpipes often provide the highest gains, typically unlocking 20–40 extra horsepower (with proper tuning) due to zero restriction. Turbo lag is reduced, and the car feels more responsive across the rev range.
- Catted Downpipes still deliver significant gains—usually 15–30 horsepower—while offering a more refined sound and keeping emissions equipment in place.
The real magic happens when you pair either with an ECU tune designed for high-flow exhaust components. This combination can unleash the RS6 C8’s full potential, especially if you’re running upgraded turbos or additional supporting mods.
Sound and Driving Experience
The difference in sound between audi rs6 c8 downpipes catless and catted is one of the biggest deciding factors for owners.
- Catless: Expect an aggressive, deep roar with more turbo whistle and pops on deceleration. Cold starts will be louder, and under load, the sound can be intoxicating—but potentially too loud for some daily drivers.
- Catted: Offers a richer tone than stock but with more civility. It’s perfect if you want to keep things neighbor-friendly while still enjoying that V8 symphony.
Emissions and Legal Considerations
Here’s the reality: in many countries and states, running catless downpipes on the street is not emissions-compliant. Without catalytic converters, harmful gases like CO and NOx are released unchecked. This can also trigger a check engine light unless tuned out.
Catted downpipes, on the other hand, use high-flow cats that balance performance and emissions reduction. They are more likely to pass inspections, though this can vary depending on local regulations. Always check your area’s laws before making the switch.
Installation and Tuning
Swapping in new downpipes on the RS6 C8 isn’t a simple bolt-on for beginners—it’s a job best left to experienced mechanics or performance shops. The process involves removing several exhaust components and sometimes lowering the subframe for access.
Once installed, tuning is highly recommended, especially for catless setups. This ensures the engine runs optimally with the reduced backpressure and prevents potential issues like boost spikes or lean air-fuel ratios.
Which Should You Choose?
Choosing between audi rs6 c8 downpipes catless and catted comes down to your priorities:
- Go Catless if you want maximum performance and sound, don’t mind the extra volume, and are building a track-focused car.
- Go Catted if you still want performance gains but need a balance of power, sound quality, and emissions compliance for street use.
Final Thoughts
The Audi RS6 C8 is already an incredible machine, but upgrading the downpipes—whether catless or catted—can transform the driving experience. From quicker turbo spool to a more thrilling exhaust note, the benefits are undeniable.
Just remember: with great power comes great responsibility. Choose a setup that fits your lifestyle, respects local laws, and keeps your RS6 C8 running at its peak. When paired with the right tune, your RS6 will deliver the kind of performance and sound that makes every drive unforgettable.