OMC GM Small Block Exhaust Manifold | Barr Marine OMC-1-912441 Starboard side log style manifold fits OMC 225 HP & 245 HP marine engines. Barr OMC exhaust manifold Direct replacement OMC log style GM small block exhaust manifold Starboard side Fits OMC 305 & 350 cu. in. engines from 1979 to 1989 Includes gaskets and mounting hardware Heavy duty cast iron Painted black Replaces OMC 909280 and 912441 Replaces Osco 2441