RCD crank trigger

Discussion in 'PSI Superchargers Tech Questions' started by john348, Feb 18, 2005.

  1. john348

    john348 Top Alcohol

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    I just bought a new RCD crank support gear drive with the crank trigger
    do i set the timming the way i always do by twisting the 44 or do you move the pick up to set it
    feel stupid asking but havent recieved it yet
    and have no idea
     
    #1
    john348, Feb 18, 2005
  2. rickey

    rickey Member

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    that's kinda funny

    I just did the same, RCD gear drive and mag 44

    my RCD hub (used) don't have magnets in it


    I was thinking about putting magnets in the RCD myself.

    [ February 18, 2005, 03:14 PM: Message edited by: rickey ]
     
    #2
    rickey, Feb 18, 2005
  3. Sportsman

    Sportsman TA/FC

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    Set the mag as usual with a timing light, then switch to the crank trigger and set it and check with a timing light. They both need to be pretty close or the mag will be out of phase with the crank trigger. Also whose pickup do you have Leahy makes a nice one.
     
    #3
    Sportsman, Feb 18, 2005
  4. john348

    john348 Top Alcohol

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    I bought the leahy pickup
    set it normal then unplug the mag and go to the crank trigger?
    Then move the pick up to set it the same as the mag was?
    after this is done and i want to move the timing a degreee or 2 do i then move the mag or pickup to make adjustments
    cant find any info to read about this
    no one i know has ever used one yet

    [ February 18, 2005, 05:41 PM: Message edited by: john348 ]
     
    #4
    john348, Feb 18, 2005
  5. Sportsman

    Sportsman TA/FC

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    Do your fine adjustments with the crank trigger pickup. Once the pickup is plugged in the mag only fires when the crank trigger sends a signal to it. Just make sure you keep the mag timing close to the crank trigger or the spark will arc inside the cap.
     
    #5
    Sportsman, Feb 18, 2005
  6. Mike Canter

    Mike Canter Top Dragster
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    When using a crank trigger once you have adjusted the rotor phasing of the mag you should make all timing adjustments by moving just the crank trigger. With a crank trigger the turning of the mag will not change the timing but it will change the rotor phasing. If you want to check the rotor phasing you can drill a hole in an old cap just on the inside of the post for number one plug wire then you can shine the timing light through the hole and see the actual location of the rotor when number one plug fires. You can then adjust the position of the mag to ensure the tip of the rotor is directly across or just slightly leading the number one post. If you change timing a lot going down the track then consideration should be given to adjusting the rotor phasing with full retard turned on or splitting the difference. If you are only changing the timing by a couple of degrees then it doesn't make that much difference.
     
    #6
    Mike Canter, Feb 18, 2005
  7. rickey

    rickey Member

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    would it be wrong to set MAG timing to 0 degress

    and then use crank trigger for setting the timing

    or should (say 30 degress) mag be set at 30 then adjust trigger so timing is still 30


    sounds like what yall are saying

    also MSD make the test cap with the hole in it, I bought mine from Doug Herbert
     
    #7
    rickey, Feb 18, 2005
  8. Gene Terenzio

    Gene Terenzio Guest

    Set up cap From MSD part # 8122
     
    #8
    Gene Terenzio, Feb 18, 2005
  9. Mike Canter

    Mike Canter Top Dragster
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    Rickey the answer is no because your rotor will be 30 degrees off and will fire the adjacent cylinder. With an 8 cylinder cap there is 44 degree between each cap post so you really have half of that 22 degrees in which you can play with before the spark jumps to the adjacent post. The spark will take the path of least resistance so if you have a bad plug wire or a fouled plug and the rotor phasing is off then the spark will go to the next closest cylinder. This is why MSD cam out with their new super large diameter cap mainly for Top Fuel because they move their timing around so much and were limited because of the closeness of the posts in the old cap. Since the new big cap is large diameter the posts are further apart. But back to the original question. To install the Mag and the crank trigger correctly can be done one of two ways. First is the simplest like what was talked about in a previous post....run the car without the crank trigger adjust the timing to 30* now stop the motor and position it so the timing mark is at 30* now adjust the crank trigger so it is directly opposite a magnet. RCD holders have a little mark to help with this. Lock everything down and start the motor and recheck the timing. If off ONLY adjust by moving the crank trigger like I said before if you now move the Mag you will change the rotor phasing relationship. Second way if you have either removed and replaced the Mag without touching the cranktrigger or want to check the rotor phasing then use a cap with a hole in it and shine the light through the hole. In this case you turn the Mag to adjust the rotor phasing (this does NOT change your timing.
     
    #9
    Mike Canter, Feb 19, 2005
  10. rickey

    rickey Member

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    thanks Mike

    I would be lost without ya

    hope to make it to track middle of March

    [ February 21, 2005, 09:35 AM: Message edited by: rickey ]
     
    #10
    rickey, Feb 21, 2005
  11. nitrohawk

    nitrohawk New Member

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    Always be sure you use degree tape on generators when first setting the timing the conventional way
    so that you can keep an eye on the generators to see if they have moved on you. If no tape take a small straight edge and mark position of generator in relation to the clamp for a reference to see if they move after running. About the only way you can get into trouble is if the generator moves because of bad or loose clamps or you change timing over 8-10 degrees without re phasing the generators.
    I have a question for you as well. Do you hold slack out of the rotors opposite of rotation when setting the phase if you are not using a timing light to set the phase?
     
    #11
    nitrohawk, Feb 21, 2005
  12. Chris Demke

    Chris Demke Super Comp

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    The timing/phasing process is much simpler with a Crank Trigger to Generator cross-over switch, MSD p/n 7990. The switch allows you to start your motor while running off of the pickup in the magneto, check the timing and make sdjustments, then (with the engine still running) flip the switch and be running off of the crank trigger, then check the crank trigger timing. I don't recommend trying to adjust the crank trigger with the motor runing [​IMG] It's prety amazing to watch the timing mark bounce around +/- a couple of degrees while running off of the magneto's internal pickup, then flip the switch to the crank trigger and see the timing mark lock into place!
    Have you been to http://www.msdpromag.com ?? There is lots of good info at MSD's web site.

    -chris

    -----
    Chris Demke
    Peen-Rite TAD

    [ February 21, 2005, 08:56 PM: Message edited by: Chris Demke ]
     
    #12
    Chris Demke, Feb 21, 2005
  13. Mike Canter

    Mike Canter Top Dragster
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    Yes I hold the generator tight to the opposite direction of normal rotation.
     
    #13
    Mike Canter, Feb 21, 2005

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