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Milltek Hi-Flow Sports Cat | Audi B7 RS4
SKU: SSXAU115
Parts
Documents
Description
The Milltek Cat Back Hi-Flow Sports Cat for Audi B7 RS4 is a direct-fitment downpipe-mounted catalytic converter engineered to optimize exhaust scavenging and flow. T304L stainless construction with 200 CPSI high-flow catalyst element maintains emissions compliance while reducing backpressure across the rev range.
Mandrel-bent 2.5" (60mm) bore with CNC-formed catalyst housing. Hand-finished T304L stainless steel resists thermal cycling and corrosion. Designed to pair with Milltek Cat-Back systems on B7 RS4 (4.2L FSI V8). Requires Stage 2 ECU software for optimal mapping. Direct OEM hanger fitment—no modification required.
Fitment & Compatibility
- Audi B7 RS4 Sedan and Avant (2006–2008)
- Engine: 4.2L FSI V8 (BNS)
- Requires: Milltek Cat-Back Exhaust System
- Requires: Stage 2 ECU Software tuning
- Direct factory fitment—uses OEM hangers and sensor bungs
Dyno-tested for flow and thermal performance against OEM catalytic converters.
Designed and manufactured in the UK with 40+ years of performance exhaust heritage. Tested at the Nurburgring.
Key Facts
| Pipe Diameter | 63.50 |
| 0 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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