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Thread: EFI basics

  1. #11
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    Quote Originally Posted by r33pwrd View Post
    Ok good enough

    just trying to understand...

    I bet adjusting the TPS also plays with timming


    I bet the EFI just opens the pulse width on the injectors....

    Many conpanys make univeral injector controlers...
    I bet or should I say I know that it doesent play with the timming.
    If the tps is out of range of the controler then yes you could not correct but if its not then it either has the right amount of fuel or not no magic there.

  2. #12
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    Willing to bet that a very small adjustment on the TPS is going to have a large reaction the the overall fuel curve. I base this on seeing large variations of signal strength readings on carbs set up in a flow benchs. Just the slightest movement would make the signal would either clime rapidly or the opposite. I am sure the contoller only gives you a narrow range to deal with to make it safe for everyone to use.

    Just my non EFI experienced .02.

  3. #13
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    Quote Originally Posted by Duke View Post
    Willing to bet that a very small adjustment on the TPS is going to have a large reaction the the overall fuel curve. I base this on seeing large variations of signal strength readings on carbs set up in a flow benchs. Just the slightest movement would make the signal would either clime rapidly or the opposite. I am sure the contoller only gives you a narrow range to deal with to make it safe for everyone to use.

    Just my non EFI experienced .02.

    So if this is the case.... then you can adjust your TPS to make the ski run Fat ....... so why cant you run tripples on a EFI again??

  4. #14
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    Quote Originally Posted by r33pwrd View Post
    So if this is the case.... then you can adjust your TPS to make the ski run Fat ....... so why cant you run tripples on a EFI again??
    rev litmer

  5. #15
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    Quote Originally Posted by Rocketman View Post
    rev litmer
    Thank for the help there.

    Why dont you answer this one, because I dont know the answer and I know you do.

    http://www.greenhulk.net/forums/showthread.php?t=33210

  6. #16
    r33pwrd's Avatar
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    so the rev limiter is the only limiting factor to tripples with an EFI?

  7. #17
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    Quote Originally Posted by r33pwrd View Post
    so the rev limiter is the only limiting factor to tripples with an EFI?
    That along with a different timing curve and fuel map.

  8. #18
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    Quote Originally Posted by r33pwrd View Post
    So if this is the case.... then you can adjust your TPS to make the ski run Fat ....... so why cant you run tripples on a EFI again??
    I guess as long as the controller can read a setting on the TPS other then what was meant to be, this might be the whole problem with it getting out of wack with only a small misadjustment. The curve isn't going to be symetrical either. Even if you could get it run at WOT the fuel requirements for mid and idle could be completely different and be be out of range of the controller. And there is the rev limit thing too.

  9. #19
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    Quote Originally Posted by WFO View Post
    Thank for the help there.

    Why dont you answer this one, because I dont know the answer and I know you do.

    http://www.greenhulk.net/forums/showthread.php?t=33210
    A book could be wrote about that but a few comments.
    The valve operation is different on the 1200 vs the 1300.
    1200 rev limit closes valve 1300 does not.
    Cleaning cycle opens the valve futher than the stop at wide open throttle.
    both cycle for cleaning at engine stop.
    If the motor on the 1200 cables valve hanging dirty ect the motor will stop trying and not open.
    Listen closley to the motor when it does the cleaning cycle,does it keep trying to close. does it try to close more than once. If so its out of adjust ment and will not work proprely.
    Most of the time on a PROPERLY proped boat valves will limit to about 6500 to 6800. if lower a compression ck should be done and as always unplug the motor roll open by hand and do a run if rpms come up close to normal then you have valve trouble of some sort. Valves can apper to be operating normaly but can be brock on the inside and only a visual inspection can be done to determin the real deal pull the cover then ck operiton.

    ONE LAST THING.DO NOT REMOVE THE CABLES FROM THE HOLDER ON THE CYLINDER. REMOVE THE 2 10MIL HEADED BOLTS ON THE CYLNDER AND REMOVE THE BRACKETT HOLDING THE CABLES. THIS WILL INSURE NO ADJUSTMENT WILL BE NESSARY LATER.

    Like Forrest Gump thats all I have to say about that.


  10. #20
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    Last edited by WFO; 07-28-2007 at 10:32 AM. Reason: tbmng

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