Milltek Hi-Flow Sports Cat & Downpipe for Audi S4 3.0 Turbo V6 B9 - Saloon/Sedan & Avant (NON GPF ONLY - Non Sport Diff Models) - Left Hand Drive Cars Only (2016 onwards) – Improved Flow, Sports Catalyst
This is Milltek's large-bore downpipe with hi-flow sports cat for the Audi S5 3.0 V6 Turbo Sportback B9 (NON GPF ONLY - Non Sport Diff Models Only) - Left Hand Drive Cars Only. It replaces the restrictive factory downpipe with a larger-bore pipe fitted with a high-flow sports catalyst in place of the standard unit, using a less dense substrate that flows significantly better than the factory cat while still treating the exhaust gases passing through it.
It sits between a stock downpipe and a full de-cat: a genuine flow gain suited to a Stage 1 or Stage 2 remap, without giving up the catalyst entirely the way a de-cat pipe does.
In the UK, a replacement catalyst on a car first registered from 1 March 2001 needs ECE R103 type-approval to be road legal, so check the EC Approved line in the specification for the version you choose.
Specifications
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System Type: Hi-Flow Sports Cat and Downpipe
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Pipe Diameter: 63.5mm (2.5")
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EC Approved: No
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Race System: Yes
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Fitting Time: approx. 1 to 1.5 hours (Milltek figure)
Key Features
- Made from T304L aircraft-grade stainless steel, which is anti-magnetic and resists discolouration
- Mandrel-bent pipework keeps a constant diameter through every bend for unrestricted flow
- 63.5mm (2.5") pipework
- High-flow sports catalyst flows better than the dense factory unit while still treating exhaust gases
- Designed, developed and manufactured in the UK by Milltek Sport
Fitment
- Audi S4 3.0 Turbo V6 B9 - Saloon/Sedan & Avant (NON GPF ONLY - Non Sport Diff Models) - Left Hand Drive Cars Only (2016 onwards)
- Audi S4 3.0 Turbo V6 B9 - Saloon/Sedan & Avant (NON GPF ONLY - Non Sport Diff Models) - Right Hand Drive Cars Only (2016 onwards)
- Audi S4 3.0 Turbo V6 B9 - Saloon/Sedan & Avant (NON GPF ONLY - Sport Diff Models Only & Without Brace Bars) - Left Hand Drive Cars Only (2016 onwards)
- Audi S4 3.0 Turbo V6 B9 - Saloon/Sedan & Avant (NON GPF ONLY - Sport Diff Models Only & Without Brace Bars) - Right Hand Drive Cars Only (2016 onwards)
- Audi S5 3.0 V6 Turbo Coupe Only B9 (LCI NON GPF ONLY - Sport Diff Models Only & WITH Brace Bars) - Left Hand Drive Cars Only (2019 onwards)
- Audi S5 3.0 V6 Turbo Coupe Only B9 (NON GPF ONLY - Sport Diff Models Only & WITH Brace Bars) - Right Hand Drive Cars Only (2017 onwards)
- Audi S5 3.0 V6 Turbo Coupe Only B9 (NON GPF ONLY - Sport Diff Models Only & Without Brace Bars) - Left Hand Drive Cars Only (2017 onwards)
- Audi S5 3.0 V6 Turbo Coupe Only B9 (NON GPF ONLY - Sport Diff Models Only & Without Brace Bars) - Right Hand Drive Cars Only (2017 onwards)
- Audi S5 3.0 V6 Turbo Coupe/Cabrio B9 (NON GPF ONLY - Non Sport Diff Models Only) - Left Hand Drive Cars Only (2017 onwards)
- Audi S5 3.0 V6 Turbo Coupe/Cabrio B9 (NON GPF ONLY - Non Sport Diff Models Only) - Right Hand Drive Cars Only (2017 onwards)
- Audi S5 3.0 V6 Turbo Sportback B9 (LCI NON GPF ONLY - Sport Diff Models Only & WITH Brace Bars) - Left Hand Drive Cars Only (2019 onwards)
- Audi S5 3.0 V6 Turbo Sportback B9 (NON GPF ONLY - Non Sport Diff Models Only) - Left Hand Drive Cars Only (2017 onwards)
- Audi S5 3.0 V6 Turbo Sportback B9 (NON GPF ONLY - Non Sport Diff Models Only) - Right Hand Drive Cars Only (2017 onwards)
- Audi S5 3.0 V6 Turbo Sportback B9 (NON GPF ONLY - Sport Diff Models Only & WITH Brace Bars) - Right Hand Drive Cars Only (2017 onwards)
- Audi S5 3.0 V6 Turbo Sportback B9 (NON GPF ONLY - Sport Diff Models Only & without Brace Bars) - Left Hand Drive Cars Only (2017 onwards)
- Audi S5 3.0 V6 Turbo Sportback B9 (NON GPF ONLY - Sport Diff Models Only & without Brace Bars) - Right Hand Drive Cars Only (2017 onwards)
Not suitable for: Audi S4 3.0 GPF ONLY - Non Sport Diff models, or any model not listed above.
Installation
Milltek quotes a fitting time of approx. 1 to 1.5 hours. Before ordering, note: 200 Cell HJS High Flow Sport Cat, fits with OE and Milltek Sport Cat back Systems. This work involves removing parts close to the turbo and engine, so we recommend fitting by a specialist with a ramp and suitable software support.
Upgrade Further
Also available from Milltek for this car: Milltek Active Valve Control Audi S4 3.0 Turbo V6 B9 - Saloon & Avant (NON GPF - Non Sport Diff Models) - Left Hand Drive Cars 16+, Milltek Cat-back Exhaust Audi S4 3.0 Turbo V6 B9 - Saloon & Avant (NON GPF - Non Sport Diff Models) - Left Hand Drive Cars 16+.
Will it fit the Audi S4 3.0 Turbo V6 B9 - Saloon/Sedan & Avant (NON GPF ONLY - Non Sport Diff Models) - Right Hand Drive Cars Only?
Yes. Milltek lists this part for the Audi S4 3.0 Turbo V6 B9 - Saloon/Sedan & Avant (NON GPF ONLY - Non Sport Diff Models) - Right Hand Drive Cars Only as well as the other models in the fitment list above.
Is it road legal?
Milltek lists this as a race part without EC approval, so it is intended for off-road and competition use.
Do I need a remap?
A suitable remap is strongly recommended, as the engine management needs to account for the change in flow and sensor readings. Speak to your tuner before fitting.
Can I use it with my standard exhaust?
It depends on the version. Some are made for the factory (OE) system and others for the Milltek cat-back, so check the notes for the option you choose.
How is a sports cat different from a de-cat?
A sports cat still contains a catalyst, just a less dense one that flows better than the factory unit. A de-cat removes the catalyst completely.
How long does it take to fit?
Milltek quotes approx. 1 to 1.5 hours.
What is it made from?
T304L aircraft-grade stainless steel, which is anti-magnetic and resists discolouration better than lower grades.
Is there a warranty?
Yes. Milltek products are covered against defects in materials and workmanship. Contact us with your order number if you have a problem.
