carb temp issue.

Discussion in 'Engine Topic' started by bigblock665, Sep 28, 2014.

  1. bigblock665

    bigblock665 Veteran Member

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    Ok so iv been fighting a nasty bog since my airgap install with a 1406 eddy. After car is warm and after its up to temp at idle I can pull into the road and stop the throttle. No bog. Cruise down the road immediately after go to punch the throttle, BOG! If I stop and idle for a minute oor two, stomp throttle... No bog.

    I have a big hood scoop, if I stuff it from air getting in I won't get a bog, ever!

    Just so everybody has an idea of the kind of bog after cruise, its like going out and stomping on a cold engine and carb.

    My question is how can I keep the carb warm so it don't bog? Don't wanna leave a rag in the scoop it could catch fire....

    How do the guys with there hot rods keep the carbs warm? Or are they NOT running air gap intake?
     
  2. hhott71

    hhott71 R.I.P 11/19/18 Lifetime Gold Member

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    Why do you think that is?
    I think that it acts enough like a choke which restricts airflow and creates a lower pressure area where the fuel flows earlier enrichening the mixture just slightly.

    Just for giggles, open the idle screws up a 1/4 to 1/2 turn so the engine still idles OK just richer than required. Then check for bog.

    Have you moved the accel pump rod to the outer hole so it gets the maximum shot and a larger shot for any given movement?
     
  3. bigblock665

    bigblock665 Veteran Member

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    Iv nodded every part of the accelerator pump system to stop this bog. The hood scoop is not sealed to the carb. So plugging the scoop is like installing a stock or cowl hood. Carb has enough air flow. When I trap heat under hood there is no bog.
     
  4. warped

    warped Veteran Member Lifetime Gold Member

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    Have you checked the carb temp in different situations? An infrared temp gun will help but I don't think it is simply a matter of the carb being too hot or too cold. There are enough guys running an air gap intake (I have the Weiand version here without problem) that if it was a significant issue one would hear more about it. Good luck.
     
  5. hhott71

    hhott71 R.I.P 11/19/18 Lifetime Gold Member

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    Heat vaporizes fuel.
    ONLY vaporized fuel will burn.
    Liquid gasoline does not burn, only its vapors do.
     
  6. bigblock665

    bigblock665 Veteran Member

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    I'm am running and old school pro stock snorkel hood scoop, most guys running airgap don't have a hood scoop cramming cold air in the engine compartment. I'm gonna run to harbor freight and grab a temp gun. If I take the hood off the car it will bog all the time unless I idle for a few minutes then jump on the throttle. I also did notice my carb is soaked with condensation when I get to work. It will be cold and soaked with water.
     
  7. muscl car

    muscl car Veteran Member Lifetime Gold Member

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    you just mentioned something that is a possible cause !!:) , you mentioned seeing your carb covered in moisture . That is called carb icing and what happenes if the inlet temp is to cold you will see ice form on the throttle plates or notice water condensation on the carb . This causes airflow disruption and perf issues

    I had the same problem with my T/ram set up but would only happen on days or in the mornings when temps got down in the low 50's . I would start noticing the engine wanting to not idle and also seeing perf issues like lack of power

    when this happens i would turn the engine off and let the engine heat soak the intake then after a few min the carb icing problem would go away

    i'm running now a Holley strip dominator which is a air gap intake plus a 2" tall open carb spacer and also running a 7" tall windshield length snorkle scoop . I still have carb icing issues when the temp is near or below 50 deg i just know what the problem is now and deal with it
     
  8. bigblock665

    bigblock665 Veteran Member

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    So could the valve cover vent tube be plumbed in the air filter base to let warm oil temp keep carb warm? Was thinking of constructing a water heated base plate for under the carb to keep in to temp.
     
  9. muscl car

    muscl car Veteran Member Lifetime Gold Member

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    For me I just don't drive my camaro when temps are nearing 50 deg and seeing high humidity . My problem is that I blocked off those heat passages in the cyl heads and that's why I have this problem

    You really need to get the intake warm so it will heat soak the carb !!
     
  10. bigblock665

    bigblock665 Veteran Member

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    Yeah my air gap don't have the crossover either. I drive my second gen to work everyday this time of year. Want to be able to drive the car any place any time and still run under 12's in the 1/4.
     

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