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Thread: Pressure Falling

  1. #1

    Default Pressure Falling

    I'm running a Holley Blue pump with the regulator that came with it (803). Is one side a bypass and the other the carb supply? I have it plumbed with each side of the regulator going to each fuel bowl inlet. The problem I'm having it after running for 5 minutes, one side steadily drops in pressure until it eventually hits 0 psi. Never had this problem before with my last Blue pump & regulator setup.

  2. #2
    Join Date
    Nov 2013
    Chicago IL


    This sounds like what happens when you get vapor lock.
    You may need to run a bleed line that goes from the fuel bowl back to the tank.
    Typically a small line (like a -3AN nitrous line) with a .020"-.040" jet in it will be plenty.
    There are also several bleed kits available on the market, that you can add to just about any carburetor.
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  3. #3


    I've never run into a vapor lock with an electric fuel pump. So you are suggesting a return line? You say from the bowl, do you mean the regulator?

  4. #4
    Join Date
    Dec 2009


    He is actually referring to a bleed line (research it). However, I prefer a return style fuel pressure regulator.
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