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HARRYS EURO - NZ's Largest Online Performance Parts Store
HARRYS EURO – NZ's Largest Online Performance Parts Store

Cast Stainless Steel Racing Catalyst, B9/B9.5 Audi A4/A5 & Allroad 2.0 TFSI

$3,040.99
This product is ready to order. Orders will have an estimated 2-week lead time.

034Motorsport is proud to introduce the all-new Cast Stainless Steel Racing Catalyst for B9/B9.5 Audi A4/A5 & Allroad models equipped with the longitudinal 2.0 TFSI engine! Designed as a drop-in replacement for the restrictive factory catalytic converter, the Cast Stainless Steel Racing Catalyst offers increased horsepower and torque throughout the powerband, reduced turbocharger lag, improved throttle response, and an enhanced exhaust note. This upgrade eliminates the primary flow limitation in the factory exhaust system, allowing you to maximize the potential of your turbocharged engine.

Optimized for increased flow and maximum performance, the Cast Stainless Steel Racing Catalyst features organic geometry and a massive 135mm diameter Euro3 racing catalytic converter in the factory location. This complete drop-in solution includes an integrated 4-bolt flange at the turbine outlet, integrated oxygen sensor bung after the catalyst, integrated 3-bolt downpipe flange, and a complete gasket/hardware kit to allow for precise fitment and ease of installation. The Cast Stainless Steel Racing Catalyst for B9/B9.5 Audi A4/A5 & Allroad is constructed from 304 stainless steel and TIG-welded for maximum durability and corrosion resistance.

034Motorsport's Cast Stainless Steel Racing Catalyst was developed entirely in-house on 034Motorsport's Development B9 Audi A4 utilizing the latest in 3D Scanning Technology, CAD Software, and Rapid Prototyping Techniques. Final production units were then tested extensively on multiple enthusiast-owned B9 Audi A4/A5, and Allroad vehicles before release.

Cast Racing Catalyst Features

  • Increased Horsepower & Torque Throughout the Powerband
  • Quicker Turbocharger Spool & Faster Transient Response (100-200 RPM Quicker Spool)
  • Enhanced Exhaust Note & Turbocharger Sounds
  • Direct, Bolt-In Upgrade for Factory Catalytic Converter
  • Engineered In-House by 034Motorsport's Engineering Team
  • Factory-Location 135mm Euro3 Racing Catalytic Converter (200 CPI)
  • 304 Stainless Steel Construction with Integrated Inlet/Outlet Flanges & O2 Sensor Bung
  • Precision CNC-Machined Flange Mating Surfaces
  • TIG Welded & Backpurged with Sand-Blasted Titanium-Look Finish
034Motorsport Cast Stainless Steel High-Flow Racing Catalyst (HFC) for B9 Audi A4/A5 & Allroad 2.0 TFSI

What's Included

  • 034Motorsport Cast Stainless Steel Performance Downpipe
  • Integrated Euro3 Racing Catalytic Converter
  • Factory Turbocharger Outlet Gasket
  • Factory Catalyst to Downpipe Gasket
  • M10 Locknuts (4)
  • M8 Locknuts (3)
  • M8x30 Studs (3)
  • Installation Guide
034Motorsport B9 Audi A4/A5/Allroad Cast Racing Catalyst Cutaway Render

Supported Vehicles

  • 2017 - 2020 Audi A4 (B9/B9.5)
    • 2.0 TFSI
  • 2017 - 2020 Audi Allroad (B9/B9.5)
    • 2.0 TFSI
  • 2018 - 2020 Audi A5 (B9/B9.5)
    • 2.0 TFSI
  • 2018 - 2020 Audi Q5 (B9/9.5)
    • 2.0 TFSI
  • Important: This racing catalyst requires a Stage 2 ECU remap to eliminate any check engine lights due to removal of the factory catalyst.

Emissions Disclaimer

  • This product is sold for racing use as well as use on vehicles not registered for on highway use.
  • By purchasing this product, you understand that this product is sold for racing use as well as used on vehicles not registered for on highway use, and that it is not legal for use on highway or street vehicles.
  • This catalyst requires a Stage 2 Racing Use Only Remap to eliminate any check engine lights due to removal of the factory catalyst.

Fitment

Make Model Years Chassis Engine
Audi A4 2017-2020 B9/B9.5 2.0 TFSI
Audi A5 2018-2020 B9/B9.5 2.0 TFSI
Audi Allroad 2017-2020 B9/B9.5 2.0 TFSI
Audi Q5 2018-2020 B9/B9.5 2.0 TFSI

 

Note: Will not fit later B9.5 cars (2021+) with v-band turbo outlets.

Note: Will not fit vehicles with gas particulate filters (GPFs).

Important: This racing catalyst requires a Stage 2 ECU remap to eliminate any check engine lights due to removal of the factory catalyst.

 
Standard Flange
 
V-band Flange
 
B9 A4/A5 High-Flow Cat Install Guide PDF

The installation of your is a relatively complex process that will take approximately one hour to complete. You can access our detailed installation guide by clicking the icon on the left.

 

Download B9 A4/Allroad/A5 Install Guide

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