launch timing retard method

Discussion in 'PSI Superchargers Tech Questions' started by rickey, Aug 19, 2019.

  1. rickey

    rickey Member

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    I have ask 4 different people and got four different ways on timing retard at launch.
    does it really matter when you retard it?

    as soon as transbreak button pressed
    as soon as transbreak button is released
    1/2 when TB button is pressed and 1/2 when TB button released
    When you go wide open throttle

    does it really matter when you retard it?
     
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  2. nitrowannabe

    nitrowannabe Member

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    Describe your car to the experts here. I probably need to know the answer also.
     
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  3. rb0804

    rb0804 Active Member

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    Depends on what you have and what your trying to accomplish. If you have a converter drive with a planetary type transmission behind it, it’s probably a good idea to pull timing while on the brake. It helps it idle down to help ease it in and out of gear. The only issue that I have with that is it makes doesn’t come up on the brake clean that way and may stumble at times, again depending on what you have.

    Other than that, it depends on what your tire is doing how and when you drop out timing, if any at all.
     
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  4. Will Hanna

    Will Hanna We put the 'inside' in Top Alcohol
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    All depends on how hard you want to hit and drive the tire at the hit.

    Don't forget about launch rpm, tire pressure and other factors
     
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  5. Bob Alberty Jr.

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    My way was as soon after the release of the brake as possible. I didn't care for backing up from the peelie with reduced timing. (Pro brake)
    Header flames, officials giving me the stink eye, and it just sounded like poop the whole time I was backing up, plus whatever duration was programmed at that time.
    Without looking at my grid, say it was dropping timing at .01 after the brake release, pull amount of timing you desire for whatever duration you desire.
     
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  6. comp altered 632

    comp altered 632 New Member

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    If you got grid then launch retard is timed from launch input.
     
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  7. Mike Canter

    Mike Canter Top Dragster
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    On the Grid when using Launch Retard it depends on where you place the first dot on the graph. If it is right on the zero seconds then retard comes on when the trans brake button is depressed while staging. If you put the first dot not on the zero seconds then retard starts when the button is released plus and time before the first dot.
     
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  8. td3829mk

    td3829mk Member

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    I have tried both retarding at idle as well as starting the sequence after TB release. I found that retarding at idle created A LOT more head temp and made the car harder to tune at the hit. I may pull a degree or two out from total at idle if I have to but that's about it.

    Whether you start the retard sequence at .01 or .10 after TB release, have tried both, both work well depending on track condition.
     
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