Maximize the performance of your Mercedes-Benz C63 AMG with the Untd. Performance 3.5″ Catless Downpipe. Engineered for the M177 4.0L Bi-Turbo V8, this catless downpipe is designed to eliminate the restrictive factory catalytic converters, allowing for improved exhaust flow and reduced backpressure. With the larger 3.5″ diameter, this downpipe ensures optimal turbo efficiency, quicker spool times, and a massive increase in horsepower and torque—transforming your W205 C63 AMG into a track-ready performance machine.