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  1. #1
    Member
    Join Date
    Mar 2009
    Location
    Rapid City, SD
    Posts
    61

    HPDI Gearcase Mod

    What's entailed in the swap over? New gearcase come with all internals/waterpump/impeller? What's freight to 32444?

    Even dumber question, what is moded on the g/c to pick up 6 MPH on the stroker it was tested on? Sounds like a lot-o-mph for <$2K

  2. Moderator 21XDC's Avatar
    Join Date
    Sep 2004
    Location
    Westland Michigan
    Posts
    65,444
    #2

    Re: HPDI Gearcase Mod (badbk)

    Strokers will gain the most as they run the LU higher than anyone else on the planet. I think this mod allows for alot higher motor height that most can't benefit 100% from.

    Marks Props 317-398-9294, 1850 East 225 South, Shelbyville, Indiana 46176 propellerman59@gmail.com http://www.marksprops.com/index.html

  3. Member
    Join Date
    Nov 2005
    Location
    Prairieville, Louisiana / Zolfo Springs, Florida
    Posts
    5,696
    #3

    Re: HPDI Gearcase Mod (21XDC)

    Yep if you can not run high then go home!

    We do run in excess of 3 inches above the pad!

    The 20' bullet will come close at 2 inches above if it is a very light load and a really good prop. Most of the time it will be 1 1/2 to 1 3/4 above.







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