Fuel flow on 2 step

Discussion in 'Manton Push Rods Top Alcohol Tech Questions' started by CjRedden, May 16, 2017.

  1. CjRedden

    CjRedden Member

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    Does anyone have a goo starting point for gpm flow on a 2 step? 526 BBC 14-71 high helix made 41 lbs of boost at 8300 RPM. I launch at 4400. Last weekends readings in cool air was 6.5 gpm on the 2 step. Does this seem high? Although the car is 2775 lbs, i usually am around 1.06 to the 60'
     
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  2. jay70cuda

    jay70cuda Member

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    Well in my BBC I always shot for 5.5 at 5800. She was very happy. Hell even tried 5.1 on accident still was fine. It was mean but nothing happened.
     
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  3. Mike Canter

    Mike Canter Top Dragster

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    5.5 to 5.7 with your setup
     
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  4. 57Chev

    57Chev Member

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    Hi Mike,

    Would it be the same with a 481X with a Screw Blower?

    Thanks
    Ray
     
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  5. Mike Canter

    Mike Canter Top Dragster

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    About a gallon more if I remember correctly. 6.5 to 6.7 gpm
     
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  6. TOL

    TOL Active Member

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    What is the general overall approach and goal for determining "how much" fuel to run during the 2-step? What are the parameters that are being monitored, or controlled to, in this process?

    I know that every engine & combo is going to have its own requirements, but what's the actual process for establishing/determining what that is for a given combo?
     
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  7. Mike Canter

    Mike Canter Top Dragster

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    Good question but will not have the answer you think you are going to get. Nothing mathematical just rule of thumb from experience.
     
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  8. scott hall

    scott hall Member

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    Well I can tell you that i'm pulling a .10 of a gallon at a time from my coverter helper until I can keep the EGTs almost flat on the 2-step....And the car likes it!
    Eventually the CAR will tell me to no longer take fuel out...and that will the right number for me....i'd try the same thing on yours....
     
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  9. TOL

    TOL Active Member

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    Scott, are you aiming to keep all the numbers equal, or are you targeting a particular EGT value? What sort of EGT values are you seeing?
     
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  10. Blownalky

    Blownalky Top Sportsman

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    Look at your average EGT while on the two step. Keep increasing the jet size until it's flat while on the two step. It will change your setup at launch so you will have to adjust to that. Leaner is meaner, .. to a point.
     
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