part throttle AFR at launch

Discussion in 'PSI Superchargers Tech Questions' started by bob szabo, May 26, 2008.

  1. bob szabo

    bob szabo FC / altered

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    A lot of great info on this forum from a lot of experienced racers about how to do two steps, throttle control, and other launch methods. Just a reminder that when a mechanical fuel injection throttle is part open, such as in preparation for a launch with throttle control setups, the air to fuel ratio is dependent on that throttle position. Part throttle enables different bypasses. Those subtract the amount of fuel going to the engine. Every bit as important as stablizing the engine with throttle control or two step is the location of the metering valve spool at that stable position, just before the hit. In some combinations of bypasses, poppets, and launch RPMs, it is possible to be lean at one throttle position, rich at another, and overly rich at another, regardless of whether you are rich at wide open throttle or not. And change that relation at a different launch RPM such as a change of converter stall speed. That also explains why one setup launches in the 0.9s when another with the same amount of launch control does not.
    Bob Szabo, author of Fuel Injection Racing Secrets and 5000 Horsepower on Methanol
    www.racecarbook.com
     
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  2. DQUES

    DQUES Member

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    What about using the Gorr valve that only uses one idle check and 2 set screws to adjust idle leakdown and stage flow gpm . Is this any better than using the Enderle style K valve ? .
     
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