SIERRA EXHAUST MANIFOLD 18-1957-1 18-1957-2

Port & Starboard
Replaces: 89011A8, 807078A6
454 Engine Cubic Inches
Fits most Mercruiser (GM) V-8 big blocks with center riser
Use with:
Exhaust Manifold Gasket: 18-0418
Mounting Kit: 18-8532