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  1. #1

    98 XPL tuning questions

    Long story short, got a ski last Nov. rebuilt the motor in my free time.
    I am having issues with tuning (which might be why the last guy trashed it).
    He had some massive R&D FA's with no reducers, 87.5 lows and 162 highs.
    where the heck do I go from here???
    I don't have a stock FA for an XPL laying around, so I am looking for suggestions as to going aftermarket while maintaining "Great"..not just good signal and still get some CFM.
    I also am looking for a good baseline tune for this ski, I am thinking 75lows and a big ? on the rest.
    this ski needs to be reliable, if I want to go fast I will get on the Ultra


  2. #2
    jonny5's Avatar
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    If you want great carb signal then get the stock airbox ..or different carbs. You dont get both.

    After testing I found the prok mod to be sub par. A good mid range and a little top end end but soft from bottom to mid.
    you will need 165 or 167.5 mains and 95/97.5 lows.
    I ran the 165 /97.5 low setup.

  3. #3
    Thanks for the info, I think I will be taking it to complete stock form, as I just got an offer I can't refuse....$$, you know how that is!
    Here is the project, I found a perfect hull and just rebuilt and trimmed it out some.
    You have any suggestions for the bone stock set-up. I am thinking all I need to do is throw away the FA's and leave the rest or even drop the lows to 77.5 (close to stock)
    Click image for larger version. 

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  4. #4
    Quote Originally Posted by jonny5 View Post
    If you want great carb signal then get the stock airbox ..or different carbs. You dont get both.

    After testing I found the prok mod to be sub par. A good mid range and a little top end end but soft from bottom to mid.
    you will need 165 or 167.5 mains and 95/97.5 lows.
    I ran the 165 /97.5 low setup.
    Do you have a good copy of hte complete wiring diagram for this ski, I think it has gone thru too many hands, the ignition seems weak and there is an issue with the key. It works, sometimes, but you can close the engine cover and it will either start working again or stop.
    Thanks again

  5. #5
    If i knew,...I wouldn't ask sea-one's Avatar
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    Jonny5, what about the pop off? where was that set at?

  6. #6
    Quote Originally Posted by sea-one View Post
    Jonny5, what about the pop off? where was that set at?
    pop off at 19, freakin perfect!
    I have actually been tuning my self to death. I started to suspect an electrical problem yesterday and went with my gut.
    I found that the battery ground wires vibrated loose, it was only enough to make it get worse and worse, crazy thing is that it would still start.
    I actually checked the connection, and it felt good, then I reached further and was able to move the bracket that actually held the negative, snuged it up with lock tight "this time" and whamo! instant badass.
    I still am looking at putting a little tape on the massive FA's and tearing it off until I get a good reading.
    Unlike some post, I will post my results. which should come soon because the ski was sold without even being finished. DAMN glad to find something. I tell you what though, everything else has been gone thru atleast twice, the retired cop buying this will be beside himself!!!
    kj

  7. #7
    long story short,
    sometimes you feel stupid if it is something simple, but yet figure it out for yourself,that is part of it. These boards can only help to a certain point, you ultimatley have to have some ability to troubleshoot, and decide what to do yourself. I was obviously overthinking the situation, but in doing so, learned more about this motor than I would have elsewise.
    Thanks guys, Keep the post comming.
    kj
    I plan on burning a tank thru her tomorrow, if things go wrong, expect me to be on here asking for help again...

  8. #8
    Ski is gone, new happy owner. Thanks for the input/help, for anyone out there looking to build a 951 and keep it user-freindly. Don't mess with the stock water passages, don't put on big FAs. Do you performance upgrades with a good impeller, and sponsons. JMHO!

  9. #9
    Oh , tbw, I used duct tape to figure out what the best tuning for carb signal would be. I ended up using about an inch of tape to keep it safe. This is an easy trick to use tuning and you don't have to spend a dime...(if you already have duct tape)

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