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Milltek HJS Hi-Flow Sports Cat and Downpipe | Audi S4 B9
SKU: SSXAU673
Documents
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
Shipping Information
This system ships in 1 box.
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