Product DetailsNew exhaust manifold for MerCruiser 330, 340, and 454 Magnum Big Block V8 marine gas engines (GM/Chevrolet). This manifold is a center rise style, will fit either side of the engine, and accepts all original mounting brackets. Comes with gaskets and all necessary plugs. Each purchase is for one manifold.
This part is new and high-quality cast iron construction. To determine if this is the correct replacement for you, look on your current part for casting numbers and match them to the cross reference below:
|Cross Reference||Part Number|
|MerCruiser||807078A6, 89011A8, 89011|
|Sierra Marine||18-1957-1, 18-1957-2|
Sierra provides premium-quality aftermarket replacements for over 6,000 marine parts, tools, and components. Sierra products are engineered to meet or exceed OEM standards, and stand up in harsh marine environments. Every new Sierra part comes with a limited lifetime warranty that covers the useful life of the product against any defects in workmanship and materials.