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  1. #1
    Mark22's Avatar
    Join Date
    Sep 2009
    Springfield, MO

    Carb Swap Question

    Is it possible to put 787 carbs on a 717? I've got a bad 787 and I was thinking about putting the carbs on my `96 HX. Will they bolt right on or does it take modification? What kind of performance increase could I expect?

  2. #2
    dghal's Avatar
    Join Date
    Jul 2008
    League City Texas
    it would take some rejetting, if the bodys actually bolt up

    if you are not competent at that you could melt a motor down.

    Not sure how much difference you would find,, it would be a gain here but lose a little there kind of thing

  3. #3
    KrunchovXPL-GTX-RX's Avatar
    Join Date
    Mar 2009
    Aiken, SC
    I think the 787 used 40s where the 717 were 38s. As dghal (btw, we are all going to hell for looking/staring at your avatar pic) pointed out, the jetting will need to be adjusted.

    If you consider that 38s can turn a stock 717 about as fast as it can be turned you would not see much, if any real gains.

    The carbs are slightly larger so you could get slightly more air and slightly more fuel (once jetted properly) but without some way to process that air and fuel (ported cases, cylinders, a pipe, pump tuning) it is just not going to do much.

    You are more likely to end up lean, and, well, that story has been played out time and again, has it not?

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