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Idle speed continues to climb

Discussion in 'Carb Fuel Systems' started by 84K30, Sep 25, 2020.

  1. 84K30

    84K30 Full Access Member

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    I’ve been messing with the high idle speed on my K30 for a few days now that it’s getting cooler out.

    Engine is a 454 and factory carb has been replaced with a Edelbrock 1406.

    A while back, Craig85 provides me with the correct idle speeds for my configuration: 700 and 1900 (high)

    It seems as though my idle speed fluctuates a bit, usually between 650 and 750, but it runs well enough.

    The high idle speed is another story. If I set it at 1900 it will slowly climb to 22/2300 before getting to operating temp. At that point I have to “blip” the throttle to make the engine drop to normal idle.

    Is this the manner in which a high idle is supposed to work or should it stay where I set it? Also, should the engine speed drop on its own once it’s to temp?

    Thanks,
    Eric
     
  2. Wumbo

    Wumbo Full Access Member

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    Engine speed will increase as it warms up, and yes, you need to tap the throttle to get it off high idle.
     
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  3. 84K30

    84K30 Full Access Member

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    Thanks for the reply. Should I set the “low end” or “top end” of the high idle speed at 1900? Meaning should it be at 1900 immediately upon startup and let it climb to whatever or should I set it where it needs to be to have it max out at 1900?
     
  4. Wumbo

    Wumbo Full Access Member

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    Personally, I set mine a bit lower. I like mine 1300-1400 at initial start up, and it climbs a couple hundred as it warms up. It's not going to affect much except fuel consumption.
     
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  5. 84K30

    84K30 Full Access Member

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    Noted. Thanks again for sharing your wisdom.
     
  6. Wumbo

    Wumbo Full Access Member

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    :cheers:
     
  7. potent rodent

    potent rodent Member

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    like stated above 1500 is all u want on hi idle, and it takes very little turning of the fast idle screw to get there
     
  8. Big Chip

    Big Chip Full Access Member

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    The CFM on a 1406 may be a little low for a 454. Does it drive ok?
     

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