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  1. #1
    OCFZR's Avatar
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    Group K 1390 powervalved

    Just wanted to let everyone with the GK 1390 kit that I successfully installed powervalves using the stock pv controller. I did not like the power band without the valves. The low end was not crisp and it had a terrible hit at 5500 rpm's. The power valves work great! The powerband is smooth throughout the rpm range and there is noticeably more low end and mid range power. I am spinning a 15/25 out of the hole now. I used 1300 valves and cut them down to match the 87 mm pistons. I also installed wave eater clips and linkage to eliminate potential problems.


  2. #2
    Moderator RX951's Avatar
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    sweet ! gotta love dem valves !

  3. #3
    Moderator OsideBill's Avatar
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    Tim you running this on an Advent? if so what settings?

  4. #4
    GPRPITMAN's Avatar
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    I think that is great that you got it working for ya. But to all that do not want to go back to powervalve my set up spun a 16-26 out of the hole and came out as strong as my triplepipe with a advent box set to a curve similiar to the race gas setting for triplepipe, Boat ran flawless. Also had jetworks mod.. My hats off to ya tim you got your boat running where you want it to thats all that counts

  5. #5
    falcondrummer's Avatar
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    I just put my 1390 pv motor together and it's awesome. I broke it in over the weekend. I will get #'s up soon. Feels really stout so far. Sounds even better.

  6. #6
    OCFZR's Avatar
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    Hi Bill,

    I have not had a chance to use my Advent yet, I need a replacement unit. I'm going to bring it to Advent this week. My last Advent failed on me when the starter got stuck on without me even pushing the start button. The stock CDI has been flawless.

    I'm sure the Advent will make a good improvement in acceleration and RPM's. I'll probably run the 84 curve and will experiment with the snap setting. Powervalves are the only way to go!

  7. #7
    MPower's Avatar
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    I've ridden both a carbed non-PV 1390 and a EFI PV 1390 and the latter was much much better. not sure if any of that had to do with EFI, but i venture to guess the PV did it.

  8. #8
    Moderator OsideBill's Avatar
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    Tim in about a month or so I will have mine together I will be running gas valves on mine. I can't wait to get this project up and running.

  9. #9
    OCFZR's Avatar
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    Bill - who did the cylinders?

  10. #10
    Moderator OsideBill's Avatar
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    They will be done by Lowell I looked at several options and finally decided on the Lowell 1390 I just sent the stuff off so it will be a bit yet.

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