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Starved Carbs at high end

Discussion in '"Stock" Alpine' started by Ashfried, Aug 31, 2015.

  1. Ashfried

    Ashfried Silver Level Sponsor

    Hey all, I could use a little advice.

    My 66 Alpine running duel Strombergs sometimes begins to stall at high speed. I first thought it was the fuel pump, because it feels like the carbs are being starved of fuel. I installed an electric fuel pump and it helped, but occasionally while doing 70+ MPH on the freeway, generally going up hill it starts doing it again.

    Note: My inline fuel filter never seams to completely fill up, even at idol. Is that normal?

    My thought is to install an Adjustable Fuel Pressure Regulator. I am hoping that will take care of the high end power fade, but I am open to suggestions.

    If so, what pressure should I set it at?

  2. RootesRacer

    RootesRacer Donation Time

    1.75psig is what the strombergs want.

    You may not be able to pull sufficient volume of fuel from the tank (could be a leak on the low pressure side of the fuel line, which will suck air into the line as opposed to leaking out).

    Reducing the pressure is not going to help with your issue though.
    If the electric pump is not internally regulated to less than 2psig, you may experience bowl overflow at idle.
  3. 65beam

    65beam Donation Time


    if your fuel tanks are original and have not been cleaned or recoated you may want to clean your fuel line or even the fitting where the line connects at the back of the car. the original fuel tank coating has been known to flake off and blocks the fuel line.
  4. Ashfried

    Ashfried Silver Level Sponsor

    My tanks were stripped and recoated a couple years ago and the fuel line seems clear. The car runs great, but when it is hot out, I am at max speed, and usually going up hill my speed will drop from 75MPH+ to a chugging 60MPH. When I let off accelerator, it takes a couple minutes to refill the carbs with gas, and I am fine again. If I pull over, it fills right away.
  5. Ashfried

    Ashfried Silver Level Sponsor

    So a Fuel pressure reg only reduces pressure, and does not add to existing pressure?
  6. Ashfried

    Ashfried Silver Level Sponsor

    low pressure side?... is that between the tank and the pump, or the pump and the carb?
  7. RootesRacer

    RootesRacer Donation Time

    between the tank and the pump.

    It is here that suction is created. If there is a leak, or the line is obstructed, the pump will not be able to make pressure at flow.
  8. RootesRacer

    RootesRacer Donation Time

    Correct. A regulator will only reduce available pressure.

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