Introduction
If you own an Audi S4 B8 (2009–2012), you already know it’s a masterpiece of German engineering. Equipped with a 3.0-liter supercharged V6 engine, the S4 blends performance, luxury, and daily drivability. But if you’re looking to unlock deeper sound, more character, and enhanced performance, the Milltek Sport Exhaust Non-Resonated is a perfect upgrade.
The non-resonated version of the Milltek exhaust is for drivers who want a more aggressive tone without compromising build quality or drivability. This guide will walk you through everything you need to know — from benefits, installation, performance gains, sound changes, and FAQs — all to help you make an informed decision.
What is the Audi S4 B8 2009–2012 Milltek Sport Exhaust Non Resonated?
The Milltek Sport Exhaust is a premium aftermarket exhaust system designed for performance-oriented drivers. The non-resonated variant replaces the factory exhaust with a freer-flowing system without mid-pipe resonators, giving you:
- A louder, deeper exhaust note
- Reduced exhaust restriction
- A sportier driving feel
Milltek’s systems are crafted from T304L stainless steel, ensuring corrosion resistance and a long lifespan.
Key Features of the Milltek Sport Exhaust (Non-Resonated)
- Material: Aircraft-grade T304L stainless steel
- Configuration: Non-resonated cat-back system
- Pipe Diameter: 2.76 inches (70mm) for improved flow
- Tailpipe Options: Polished, black ceramic, or titanium
- Fitment: Direct bolt-on for Audi S4 B8 (2009–2012)
- Sound: Louder and more aggressive than stock or resonated versions
Why Choose the Non-Resonated Version?
The main difference between resonated and non-resonated systems is sound control.
- Non-resonated: Louder, rawer tone with more engine character
- Resonated: Quieter, smoother tone suitable for subtle upgrades
The non-resonated Milltek option is ideal if:
- You want maximum exhaust sound
- You enjoy a more race-inspired tone
- You don’t mind a slight increase in cabin volume
Performance Benefits You Can Expect
Installing the Audi S4 B8 2009–2012 Milltek Sport Exhaust Non-Resonated can bring multiple improvements:
1. Increased Horsepower and Torque
The freer-flowing design reduces backpressure, allowing the engine to breathe better. Gains of 8–12 HP are common with this upgrade.
2. Faster Throttle Response
With reduced exhaust restriction, your S4 reacts quicker to acceleration inputs.
3. Weight Reduction
Milltek exhausts are often lighter than the OEM system, improving weight distribution and performance.
4. Enhanced Driving Experience
From the moment you start the car, the deeper tone adds excitement to every drive.
Sound Profile – What to Expect
The non-resonated setup produces:
- A deeper growl at idle
- A roaring, aggressive note under acceleration
- Crackles and pops on downshifts (especially in sport mode)
Note: This system may produce noticeable cabin drone at certain RPMs, especially on the highway. Some drivers love it, while others prefer the quieter resonated version.
Step-by-Step Installation Guide
Tools You’ll Need
- Socket set (metric sizes)
- Ratchet and extensions
- Torque wrench
- Exhaust hanger removal tool
- Jack stands or a lift
- Penetrating oil
Installation Steps
- Raise the Car Safely – Use a lift or jack stands on level ground.
- Remove the Stock Exhaust – Unbolt the OEM system from the catalytic converter back.
- Lubricate Hangers – Spray penetrating oil on rubber hangers for easier removal.
- Position the Milltek System – Start from the front and work towards the rear.
- Align the Pipes and Tailpipes – Ensure they’re centered and not touching heat shields.
- Tighten All Clamps – Torque to manufacturer specifications.
- Test for Leaks – Start the car and check all connections.
Installation Time: 1.5–2 hours for a professional shop, 3–4 hours for DIY.
Tuning Considerations
The Milltek exhaust can be used with stock tuning, but pairing it with a Stage 1 or Stage 2 ECU remap can unlock further gains:
- Stage 1: +20–30 HP
- Stage 2 (with pulley upgrade): +60–80 HP
Maintenance Tips for Longevity
- Clean tailpipes regularly to prevent carbon buildup
- Inspect clamps and hangers every 6 months
- Avoid harsh chemicals when cleaning
- Keep an eye out for loose connections or rattles
Real-World Driving Impressions
Owners report:
- More excitement during spirited driving
- Noticeable difference in sound even at idle
- Better mid-range pull thanks to freer exhaust flow
Some also note that cold starts are very loud, so be mindful if you have sensitive neighbors.
Pros and Cons at a Glance
Pros
- Aggressive, sporty sound
- Improved performance and response
- High-quality stainless steel construction
- Direct bolt-on fitment
Cons
- Louder cabin noise
- Possible drone at cruising speeds
- Higher price than some alternatives
Alternatives to Consider
- Milltek Resonated Cat-Back – Quieter option
- APR Cat-Back System – Slightly different tone
- AWE Touring Edition – Balanced performance and comfort
How Much Does It Cost?
As of 2025, pricing for the Audi S4 B8 Milltek Non-Resonated system ranges between:
- $1,600 – $2,200 USD depending on tailpipe finish and supplier
- Installation: $150–$300 at most performance shops
Where to Buy
- Milltek Official Website
- Authorized dealers
- Performance parts retailers
- Online marketplaces like ECS Tuning or XtremePower
Always ensure you’re buying from an authorized Milltek distributor to avoid counterfeit products.
Final Verdict – Is It Worth It?
The Audi S4 B8 2009–2012 Milltek Sport Exhaust Non-Resonated is a premium upgrade for enthusiasts who want more sound, better performance, and high-end craftsmanship. While it’s louder than the resonated version, many drivers feel the aggressive tone perfectly matches the S4’s personality.
If you’re ready to give your S4 a voice that matches its performance, this exhaust delivers in every way.
Frequently Asked Questions (FAQ)
1. Will this void my warranty?
It depends on your dealer and the country’s laws. In most cases, only related parts (exhaust/emissions) may be excluded.
2. Is it street legal?
In most countries, yes — but always check local noise regulations.
3. Can I install it myself?
Yes, if you have the tools and mechanical knowledge.
4. Will it fit my S4 without modifications?
Yes, it’s designed as a direct bolt-on.
5. Does it require tuning?
No, but tuning can enhance performance.