4.75-Inch 200 Cell High-Flow Catalytic Converter Downpipe

The Integrated Engineering ProCore Downpipe for the Audi B9 A4 and A5 is engineered to significantly increase exhaust flow and enhance the exhaust note. It features an in-house designed 4.75-inch, 200 CPI catalytic converter with advanced coatings that manage emissions, ensuring compliance with factory ECU requirements and preventing check engine lights. It is designed as a bolt-on, direct-fit component, simplifying installation with an average time of 2-3 hours and eliminating the need for cutting or welding. The high-flow design unlocks the full power, torque, and spool potential of upgraded hardware and tuning. Dyno testing performed on a Stage 2 equipped B9 A4 demonstrated significant power gains of up to 126 HP and 183 TQ over stock. The ProCore Catalyst’s design and emissions coating process allow it to pass vehicle readiness monitors without triggering the check engine light, offering performance benefits without the common drawbacks. This downpipe is specifically designed for the Audi A4 and A5 models from 2017-2020 (B9/B9.5).