Sierra International Manifold With Mounting Package For MerCruiser 2.5L 153 Cid & 3.0L 181 Cid Engines 18-1954-1. It is designed for use in Mercruiser 2.5L (153 CID) and 3.0L (181 CID) (1983-1989) engines with a Rochester carburetor with a 5-bolt...