WOT and fuel pump issues

Discussion in 'Fuel and Air Systems' started by mopardemon340, May 6, 2018.

  1. mopardemon340

    mopardemon340 Well-Known Member

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    anyone know of any issues with the holley black lable fuel pumps? mine isnt giving me reliable pressure even with it on a regulator.. it reads 7psi a few months ago with my new carb install. then last night it was reading 2 psi so we adjusted it back to 6psi.. then after turning the car off and then starting it again the went up to 9psi. its this a common issue with them not giving a constant pressure.. if i replace this pump what would be a good inline?

    next question. im unable to get to WOT with my peddle to the floor. if i adjust it at the carb then the carb wont be set right cause it will pull on the carb. how are you guys getting WOT if you need more travel on the peddle?
     
  2. gtsdude

    gtsdude Well-Known Member

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    Maybe check your regulator first, take it apart and make sure there isn't any junk in it. I would also pull the fuel pump apart for the same. I have a big end copy of that pump on my dart, been on there for over 10 years with no trouble. On the throttle not going wide open, need more info, what intake and carb? stock throttle cable or aftermarket?
     
  3. mopardemon340

    mopardemon340 Well-Known Member

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    Qf 850, rpm air gap, lokar cabke. I was getting g wot with the holley 770 but with the qf I down would taking the pedal out of the car and bending it a little work? it is there other options
     
  4. threewood

    threewood Well-Known Member

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    I would suspect the regulator. Which one are you running? I am running a black pump and QF regulator (which I'm certain is the same as every other one) and it holds 6psi but the regulator is loud and thumpy.

    Variable voltage to the pump can cause some fluctuation but I doubt it would be measurable unless it dropped way down.
     
  5. mopardemon340

    mopardemon340 Well-Known Member

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    I have a red qf regulator and it's set up as a bypass. I dont think the issue is voltage cause I set it up with a relay. None of this happened last year everything was great. If there's was something stuck in my regulator or pump how would it get there. I run filters both before and after the pump. And these a screen on my puck up tude.
     
    Last edited: May 6, 2018
  6. gtsdude

    gtsdude Well-Known Member

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    Yeah I would try bending the gas pedal if there isn’t any other adjustment left
     
    • Like Like x 1
    • diymirage

      diymirage HP@idle > hondaHP@redline FABO Gold Member

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      Liquid filled fuel pressure gauge?
      If all your going on is the gauge, I would make sure the gauge is trustworthy

      As for the WOT, just drill a hole closer to the centerline of the throttle shaft and install the cable there
       
    • mopardemon340

      mopardemon340 Well-Known Member

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      Its liquid filled but summit brand so not the most expensive
       
    • sireland67

      sireland67 Well-Known Member

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      I have had alot of trouble with liquid filled gauges, I actually have an autometer one that is stuck at 3 psi with nothing attached, it worked fine...
      Parked it an un-heated garage for one winter, it was done.
       
    • mopardemon340

      mopardemon340 Well-Known Member

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      i just put an secondary gauge on my fuel rail and it reads 6.5. the one on the reg dopes down to 5. the gauge on the reg is a summit and liquid filled while the other is a mr gasket not liquid filled.. ill keep an eye on both. really dont want to rip my pump or reg apart but if i have to i will if i see my secondary drop down..

      bending the pedal helped and not i get WOT