Notched throttle linkage?

Discussion in 'PSI Superchargers Tech Questions' started by 32 bantam, Sep 11, 2014.

  1. 32 bantam

    32 bantam Member

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    Latest ND has Todd Veney talking about a "notched" throttle linkage to set staging RPM. Can someone explain that? pictures?
    Thanks,
    Steve
     
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  2. rb0804

    rb0804 Active Member

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    One would cut a groove into the throttle cable and use a hair pin in the groove. When you bring the engine up, the driver feels resistance and knows that he is at the correct rpm. When he/she swaps feet, the hair pin slides out of the groove to allow full throttle. Shims can be added or removed between the hair pin and the throttle linkage bracket to tailor the stage rpm up or down. This is an old "farmers trick" and works well if you have a driver that creeps the rpms up or down while he/she rolls in to stage. This really only applies to blown clutch cars in the alky classes because just about every where else a two step is legal to run, and of course converter cars are allowed a two step. While we are taking about ways to control stage rpm some converter cars use a two way loud pedal to control throttle blade opening while on the two step.
     
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  3. 32 bantam

    32 bantam Member

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    I use a air throttle controller to set launch RPM. I run the 7.0 pro class and the rules for the HHR and March meet do not allow air throttle control. BUT they do allow a 2 step. And we are going west this winter to run both!
    So starting this year I have used the 2 step and the air throttle controller so the blades aren't wide open along with the barrel valve. It is working well. But I can't use it in Calif. sooooooooooo I'm looking at ways to find a throttle "stop" or indicator when on the two step without guessing. I would be a little concerned about compromising the throttle cable....it isn't that big! Plus I can't set it until the second bulb is on and if I'm not 1st in .... I could get a quick tree and really screw things up!!!
    Thanks for the explanation.....I will keep thinking about this.
    Steve
     
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  4. rb0804

    rb0804 Active Member

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    They make morse cables in different thicknesses, you just purchase a thicker one and machine a groove into it. You can run a heel toe type throttle pedal also, which is what converter equipped funny cars and dragsters HAD to use before they allowed the two step for the converter cars.
     
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  5. GregM784

    GregM784 Member

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    This is the lamest thing i've ever seen.

    Yup, they don't allow launch controllers. That is why i've never even ventured into that class. Why allow a 2 step and not an air launch. That is ridiculous. I'll stick with NE/1. :)
     
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