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Sierra Mercruiser GM Big Block Exhaust Manifold - 18-1957-2
Item: #1555728 | Part Number: 18-1957-2$398.40
Description
The Sierra Mercruiser GM Big Block Exhaust Manifold 18-1957-2 is a heavy-duty replacement designed for MerCruiser 330, 340, and 454 Magnum Big Block V8 engines. Built from cast iron and finished in black, it delivers reliable exhaust performance for freshwater use. Includes gaskets, riser studs, and drain elbow for a complete installation.
Sierra Mercruiser GM Big Block Exhaust Manifold - 18-1957-2 Item # 1555728
Description
Sierra Mercruiser GM Big Block Exhaust Manifold for MerCruiser 330, 340, and 454 Magnum Big Block V8 marine gas engines
Features:
- Interchangeable between port and starboard side
- Ideally suited for freshwater applications
- Heavy duty cast iron
- Painted black
- Includes all gaskets, short riser studs, drain elbow, and plugs
- Manifold mounting not included
Replaces:
- Barr: MC-1-89011
- GLM: 51240
- HE: 9011
- Mallory: 9-40506
- Marine Power: 0991-1000
- Mercruiser Stern Drive:
- 807078Q07
- 807078T08
- Osco: 9011