Boat engine noise

[spow]

I need to quiet the noise from my boat engine.  The boat has a big v-8 and at speed the noise on the deck is too lound for the family to enjoy the ride.  The engine is in a 4 x 8 x 3 engine compartment below the deck, accessed via a hatch.  There is currently no insulation - only gel-coated fiberglass. 
From reading your site I think I need to do a couple of things.  First would be to close off openings where sound can pass unobstructed from the engine room to the deck.  Then I need to apply some insulation to the engine room ceiling and walls.  Considerations are safety, effectiveness, cost, weight, and ease of installation.  I'm not expecting total silence - just noise reduction to a less annoying level.    A single layer of SSP foam would probably help.  Would using the MLV with 1/4" closed cell foam work better?  Or a layer of MLV with SSP foam?  What do you recommend?

Thanks,

Stephen

[Randy S]

We've done this before with great results.
I would first coat the compartment with our sound dampening paint in a 3/16" thick coverage.
Then I would adhere(complete coverage) our SSP foam mat thicker the better to to all surfaces and make sure the hatch has a new seal.

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Feel free to contact me direct if you would like.