crank trigger versus timing setting

Discussion in 'PSI Superchargers Tech Questions' started by WIDEOPEN231, Jul 20, 2023.

  1. WIDEOPEN231

    WIDEOPEN231 Member

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    To answer a question. When setting the distributor and crank trigger or phasing the two. How close to same should they be or better stated how far off and the plug fire at the programmed setting.?
    Working with A/fuel team and having issue. Thinkling difference in the two settings and what we program it for is issue. Example lets say mag set at 58 and trigger at 70. What would be effect wehn going to full timing?
     
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  2. Mike Canter

    Mike Canter Top Dragster
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    Physically since you have eight terminals on the cap there is a terminal at every 45 degrees. So if you half that to 22.5 degrees means if you retard 22.5* or more the spark can jump to the adjacent terminal on the cap. That is ideal but if one plug wire is a little bad or the plug is fouled then the spark is going to take the path of least resistance. For safety I would say 18 degrees of retard is max of movement of the rotor in relationship to the terminals in the cap.

    what are your issues?
     
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  3. Krister johansson

    Krister johansson New Member

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    45 degree ?? 90 crank degree
     
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  4. Mike Canter

    Mike Canter Top Dragster
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    Talking about the separation of the terminals in the mag cap
     
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  5. WIDEOPEN231

    WIDEOPEN231 Member

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    when mag is already 12 less than trigger and you pull 12 to 15 at the hit and add in 5* thru box. Throw in a dead hole and it seems recipe for not good results.
    Not that we are having a parts destroying issue.We are having some issue causing a tuneup that has run 5.25 to 5.32 at different 3 different tracks and with dead hole or two,but that different issue and just part of A/fuel.
    Just looking at this as possible part of issue with tuneup going off track. Looking at other things to and trying not to take one thing as problem and overlooking others.
    question. Would the 12* difference limit the actual ignintion timing up or down.
     
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  6. Mike Canter

    Mike Canter Top Dragster
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    Check and make sure you cable to the crank trigger is no where close to or parallel to the high voltage coil wire or any plug wires.the high voltage out of the mag is enough to put a false trigger pulse on the crank trigger and cause the mag to erroneously fire. Ensure the crank trigger cable runs by itself.
     
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  7. Bob Meyer

    Bob Meyer Comp Eliminator

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    Good discussion Mike, it was a godsend when big cap and long rotor was invented ! Now if anyone could figure out a way to mount two caps the size of a wall clock on the car , the terminals would be plenty far apart ! :D:):eek:
     
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  8. kosky racing

    kosky racing Comp Eliminator

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    Bob it will still turn at the same speed
     
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  9. kosky racing

    kosky racing Comp Eliminator

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    Had to give you something to think about and wake you up- miss seeing you and all the oldies
     
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  10. Krister johansson

    Krister johansson New Member

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