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  1. #1
    Moderator beerdart's Avatar
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    Pro 785 Base Gasket Thickness

    What is the recomended thickness for the base gasket on a pro 785 stock motor?
    What would be the gaines or losses of reducing the thickness to 1/64" that should change the comperssion but also change the port timming.?


  2. #2
    800AMSOIL4U's Avatar
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    0.55 mm on my stock base gasket. That was measuring just the gasket not the gasket + the sealing material on it. With it the measurement is 0.79 mm. I have know idea how much it will compress.

  3. #3
    Connecticut CrazyA's Avatar
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    Quote Originally Posted by beerdart View Post
    What would be the gaines or losses of reducing the thickness to 1/64" that should change the comperssion but also change the port timming.?
    In theory, that's exactly what would happen. The effects... ? Probably not desirable.

    Use the proper base gasket and maintain port timing, then use one piece of the Pro 785 head gasket to raise compression.

    The head gaskets on the Pro can be split for a little "cheater boat" action!!!

  4. #4
    bowsniper's Avatar
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    Hehehe. Thats exactly what I did Shhhh! Dont tell anyone.lol

  5. #5

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    Lowering the deck height by reducing the base gasket thickness' will increase the compression & give you better bottom end torque (marginally).
    But you will also be reducing peak rpm. Lowering the cylinder .010" - .030" will not increase the torque enough to pull a taller impeller..

    You can probably find base gaskets with different thickness' from Watcon.

    Have fun...
    Randy

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