4" High-Flow Catted Downpipe

The CTS Turbo 4" High-Flow CAT is engineered to significantly improve exhaust flow for BMW N20 4-cylinder engines found in various F-series chassis. This high-flow catalytic converter replaces the restrictive factory unit, freeing up exhaust gases to deliver a noticeable increase in engine power and a more pronounced, aggressive exhaust note. Drivers can expect faster turbo spool and reduced backpressure, contributing to a more responsive and engaging driving experience. Constructed from durable, fully TIG welded stainless steel with a CNC machined flange and direct-fit bracket, this component is built for longevity and ease of installation. It is designed to provide a power increase of 25-35HP when paired with a stage 2 tune, though actual gains may vary depending on octane levels. Proper tuning with Bootmod3 is required to prevent check engine lights (CEL) and ensure optimal operation. Software is essential to avoid CEL illumination. This product is strictly intended for off-road race use only and is not legal for installation on highway or street vehicles. It is specifically designed for N20 engines, identified by ULEV emissions ratings; it is not compatible with N26 engines (SULEV). The CTS Turbo 4" High-Flow CAT fits a wide range of BMW models including the F22 228i, F23 228i, F30 320i and 328i, F31 328i xDrive, F32 and F33 428i, F34 328i xDrive, F36 428i, and F10 528i, across both standard and xDrive variants, all equipped with the N20 2.0L engine.