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You didn't say what kind of carb or choke set up you have. Thats kind of important to know.
But not because its one kind or another. Carbs are personal choice like headers or tires with each doing what the owner wants them to do or thinks they want them to do.
The problem you described is rough running and/or high speed miss. Holley, Qjets and Edelebrock are all good units each has strengths and weaknesses. I'd suspect you have a rich mixture problem and not a timing problem. If you have an non-computer controlled HEI setup correctly its almost set it and forget it, hot or cold.
When the temp drops as you describe the air gets denser and adds fuel to the mix. I don't think you have a condensation problem. If your fuel mix is already to rich cold air just makes it worse. At start up it rough idle and high speed it it will feel like a miss. What happens when cold air is introduced the fuel changes from a mist to droplets. Droplets won't burn right if at all, hence the rough idle and miss, mist on the other hand does burn nicely. An air fuel mix gauge won't help identify the problem.
No matter which carb you have you need to better manage the fuel delivery to the carb. Remove all of your spark plugs clean regap and reinstall. Install a fuel pressure regulator. Set it to 5.5 psi for an Edelbrock and you have eliminated that as possible problem. There's nothing else you need to do with an Edelbrock.
With a Holley once you have set the primary and secondary bowl sight levels you will need to watch the fuel level thru the sight hole in the primary bowl particularly when the pump cycles. If the pump cycle over fills the bowl and causes the fuel to run out of the bowl decrease the fuel pressure slightly and wait for the next cycle. Stop when the fuel stops sloshing out. I'd start at 5.5 on the Holley and go up or down from there. Holley says you don't need a regulator with their carb which is hard believe because they make the best low dollar fuel pressure on the market. Buy the one that goes from 4.5 to 9 psi.
For a Qjet, once you are sure the float is set right, set your pressure reg at 5.5 and drive it for awhile and see what it does. There's no other way to match a regulator to a Qjet other than trial and error.
This is problem is a little more complex than a black and white solution so trial and error are in order. Remember if it keeps running rich during you efforts to fix this you need to clean the plugs between each trial. Also, you can get it too lean which is tough on valves and pistons.
Good luck.
Lester
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