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  1. #1
    bowsniper's Avatar
    Join Date
    Aug 2008

    Upper and Lower Case

    I was checking out the differences in the 750 upper case and the 785 Pro upper cases to see what is actually different. In the pics are 2 of the differences I saw.
    First one is where there is a big slot cut into the area where my finger points to. its on both sides.

    The other is a flat area that is curved somewhat.. looks like to direct fuel mixture possibly.

    Other than that, the bottom cases are identical. Is this why some take the 785 pro upper and use it on thier 750?

    What kind of gains could be had by using the pros upper on the 750?
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  2. #2
    1FASTXC's Avatar
    Join Date
    Mar 2007
    The "slot" in the top pics is for better flow from the reed cage area directly into the transfer ports. If you were to have a performance shop port your cases, that is one of the things they would do. The notch in the bottom pics i believe is just clearance for the rod due to a difference in rod length and or stroke difference or both. Nice to see side by side comparisons.

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