Akrapovic BMW M140i, M240i, 340i & 440i Sports Cat Downpipe (B58 Engine)The Akrapovic high flow BMW B58 Gen1 downpipe is constructed using high quality stainless steel and, once fitted to the Evolution Line exhaust, it creates a complete system from the manifold to the tailpipes that will further enhance the performance figures: both the torque and power outputs. It incorporates a sporty catalytic converter. This optional downpipe produces an enhanced sound that delivers a pure racing emotion and fantastic feedback at