This is a used marine Intake Manifold for small block OMC Stringer stern drives. The OMC/BRP part number is 3978469. The GM casting numbers may be but are not limited to 3978469 GM8 C241. This Intake Manifold fits many OMC Stringer stern drives from the 1980's with a Chevy V8 4 barrel engine. It may fit more models than this. Is used in some small block chevy racing.