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  1. #1
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    good rpm. low mph??

    I have a motor I repowered my ranger 520 vx with motor is fresh rebuild running perfect and turning up good rpm with several different prop variations on it and just can't get over 50s mph. could motor have had wrong ratio gear case

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    #2
    What motor?



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    #3
    2004 225 optimax

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    #4
    Is the lower unit original?
    What is the serial number on the motor?



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    #5
    I'd say the lower isn't original. I'll get serial

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    #6
    Quote Originally Posted by Jimmy1983 View Post
    I have a motor I repowered my ranger 520 vx with motor is fresh rebuild running perfect and turning up good rpm with several different prop variations on it and just can't get over 50s mph. could motor have had wrong ratio gear case
    If it's a LU that's geared lower than your original, it should be over-revving if that's all you can get out of it speed-wise. Can you hold it at WOT and not over-rev?
    If so, I would be concerned about the motor itself.
    How is the holeshot?

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    #7
    has good hole shot with 21p on it but it revs out wot. 25p not very good hole shot but turns up too like 5200 wot

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    #8
    SN: 1B117968. I'm just wondering if guy I got motor pieced the wrong gear case on it. motor runs great just can't get no wot speed

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    #9
    gonna try a 23p tempest plus see where that puts me

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    #10
    Quote Originally Posted by Jimmy1983 View Post
    gonna try a 23p tempest plus see where that puts me
    Best plan ^^^
    That boat should come out of the hole like a missile with a 21p on it.

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    #11
    ya one boat length with that 21 on there

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    #12
    should over rev a 23 temp, 25 with one large hole plug in other 2 out aughta be right on unless someone put a 1;62 on it then 23 might work
    .................................................. ...the scariest thing in life is the unknown ...................................

  13. Member
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    #13
    shouldn't I be seeing more than 50 mph though

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    #14
    Are you recording speeds with a GPS?



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    #15
    yes I am

  16. Member
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    #16
    I have the same motor on a 20' Pro-Craft and run 68 GPS @ 5850 RPM turning a 25 Fury with all holes open. Good holeshot also