Milltek HJS Hi-Flow Sports Cat and Downpipe | Audi S4 B9

Name: Milltek HJS Hi-Flow Sports Cat and Downpipe | Audi S4 B9
Brand: Milltek
SKU: SSXAU673
Price: 2733.57 USD
Availability: InStock

SKU: SSXAU673

$3374.78 $3374.78 $2733.57 $2733.57

Parts

MSAU704: High Flow Cat Assembly - MSAU704

Documents

Fitting Kit SSXAU673

Description

Milltek HJS Hi-Flow Sports Cat and Downpipe for the Audi S4 B9

Engineered as a direct replacement for the factory downpipe, mandrel-bent throughout to maintain flow and fitted to the OE mounting points.

Key Features

Premium Materials: T304Lstainless steel for durability and lasting corrosion resistance.
Enhanced Performance: 2.50" (63.50mm) mandrel-bent pipework improves exhaust flow for sharper throttle response.
Direct Fitment: engineered as a bolt-on replacement for the factory system.
Race Use: intended for track and off-road use— check local regulations before road use.

Technical Specifications

Pipe Diameter: 2.50" (63.50mm)
Material: T304L Stainless Steel
System Type: HJS Hi-Flow Sports Cat and Downpipe
Fitting Time: 1.00 to 1.50 hours

Compatibility

2017 and later S5 3.0 V6 Turbo Sportback B9 (Non Sport Diff Models Only) - Left Hand Drive Cars Only
2017 and later S5 3.0 V6 Turbo Coupe/Cabrio B9 (Non Sport Diff Models Only) - Left Hand Drive Cars Only
2017 and later S5 3.0 V6 Turbo Coupe Only B9 (Sport Diff Models Only & Without Brace Bars) - Left Hand Drive Cars Only
2017 and later S5 3.0 V6 Turbo Sportback B9 (Sport Diff Models Only & without Brace Bars) - Left Hand Drive Cars Only
2017 and later S5 3.0 V6 Turbo Sportback B9 (Sport Diff Models Only & WITH Brace Bars) - Left Hand Drive Cars Only
2017 and later S5 3.0 V6 Turbo Coupe Only B9 (Sport Diff Models Only & WITH Brace Bars) - Left Hand Drive Cars Only
2016 and later S4 3.0 Turbo V6 B9 - Saloon/Sedan & Avant (ONLY - Non Sport Diff Models) - Left Hand Drive Cars Only
2016 and later S4 3.0 Turbo V6 B9 - Saloon/Sedan & Avant (ONLY - Sport Diff Models Only & Without Brace Bars) - Left Hand Drive Cars Only

Why Choose Milltek?

Every system is precision-built to deliver the sound, flow, and quality that define the Milltek difference.

Designed and manufactured in the UK with 40+ years of performance exhaust heritage. Tested at the Nurburgring.

Key Facts

Pipe Diameter	63.50
1 to 1.5 hours to fit (including removing OE system)
Race Product	Yes
EMarked	No

System Fitment List

- Audi > S4 > 3.0 Turbo V6 B9 - Saloon/Sedan & Avant (ONLY - Non Sport Diff Models) - Left Hand Drive Cars Only > 2016 and Later
- Audi > S4 > 3.0 Turbo V6 B9 - Saloon/Sedan & Avant (ONLY - Sport Diff Models Only & Without Brace Bars) - Left Hand Drive Cars Only > 2016 and Later
- Audi > S5 > 3.0 V6 Turbo Coupe Only B9 (Sport Diff Models Only & WITH Brace Bars) - Left Hand Drive Cars Only > 2017 and Later
- Audi > S5 > 3.0 V6 Turbo Coupe Only B9 (Sport Diff Models Only & Without Brace Bars) - Left Hand Drive Cars Only > 2017 and Later
- Audi > S5 > 3.0 V6 Turbo Coupe/Cabrio B9 (Non Sport Diff Models Only) - Left Hand Drive Cars Only > 2017 and Later
- Audi > S5 > 3.0 V6 Turbo Sportback B9 (Non Sport Diff Models Only) - Left Hand Drive Cars Only > 2017 and Later
- Audi > S5 > 3.0 V6 Turbo Sportback B9 (Sport Diff Models Only & WITH Brace Bars) - Left Hand Drive Cars Only > 2017 and Later
- Audi > S5 > 3.0 V6 Turbo Sportback B9 (Sport Diff Models Only & without Brace Bars) - Left Hand Drive Cars Only > 2017 and Later