Six Pack high idle after hit

What better place than here to find out what the problem is with my 440-six pack road runner. The car runs great at idle and with the pedal mashed. My problem is the idle runs 1000-1500 rpm higher than normal (900 rpm) after I make a pass, or hammer it on the street. I am running the stock set up with vacuum secondaries on a stock intake. Is the problem I'm describing what the electric selenoids are for on the original cars? Mine does not have them. Thanks, Tom

When it idles high have you physically tried to close each carb? Maybe one is hanging up. Overtightening the bases can cause this. Sometimes my carbs fall off but they never bind.

Thanks Tom. I haven't checked the base tightness. Usually I notice it when I drive on the street. I'm probably due for some new gaskets under the carbs anyway. I'll give it a try. I have not physically gotten out to see if or where they are hanging up. It's usually idling soo high that if i were to put it into park or neutral...it would rev pretty high. What were the solenoids used for on the originals?

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Thanks Tom. I haven't checked the base tightness. Usually I notice it when I drive on the street. I'm probably due for some new gaskets under the carbs anyway. I'll give it a try. I have not physically gotten out to see if or where they are hanging up. It's usually idling soo high that if i were to put it into park or neutral...it would rev pretty high. What were the solenoids used for on the originals?

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The solenoid was used to prevent run on "dieseling". The solenoid is energized with the key in the on position and shuts off(relaxes) when the key is shut off. When the screw is adjusted properly, the center carb throttle plate will shut after turning the car off and prevent run on.

But this is likely not your problem. If it's not a vacuum leak or some other adjsutment issue or hang up as Tom said, you may want to check that the outboard idle mixture screws are properly adjusted. Try 1/2-3/4 a turn from seated to start and work from there. I have corrected the problem you describe by trimming(adjusting) the outbaord idle mixture screws. These are very sensitive and just a 1/8-1/4 turn one way or the other can lead to various problems.

MB