CTS Turbo 8V/8Y RS3 and 8S TTRS 2.5T EVO 3.5″ Single High-flow Cat

The CTS Turbo 3.5″ High-Flow Catalytic Downpipe is a premium performance upgrade designed specifically for the 2018+ Audi 8V and 8Y RS3 and 8S TTRS equipped with the 2.5L TFSI EVO (EA855) engine. Engineered to replace the restrictive factory main catalytic converters, this downpipe is constructed from durable 304 stainless steel and features a large-bore single 3.5″ design with a high-efficiency 200-cell catalytic converter to significantly increase exhaust flow, reduce backpressure, and unleash the true sound and performance potential of the 2.5T engine. Developed using advanced 3D scanning and CAD simulation, the system is optimized for smooth gas flow, evenly splitting exhaust gases into two outlets while maintaining compatibility with factory oxygen sensor placement and providing a perfect OEM-like fit.

A Y-pipe is included to ensure direct fitment with the factory exhaust system, and precision-machined V-band and laser-cut flanges offer secure, leak-free installation. This downpipe delivers an aggressive, motorsport-inspired exhaust note under load while remaining drone-free during normal driving. Although a check engine light (CEL) will occur with stock ECU software, the system is designed to be used with Stage 2 tuning software for optimal performance and drivability. For serious Audi RS enthusiasts looking to extract maximum power and sound from their EA855 engine, the CTS Turbo High-Flow Downpipe is a must-have bolt-on upgrade.