Car won't run in Az......

[azfordman]

I had a couple of Holley 4 barrels sitting here and I took them apart to look at the jets. They were all #61 jets, same as the carb currently on the car. The two carbs I took apart did not look like they had jets in the secondaries, which I thought there would be, just a flat plate bolted to another plate and gasket. The inner plate would not come off without major force, so I left it alone. Since I had an abundance of #61's, and it was a holiday weekend, I decided to drill a couple of them out (not recommended, I know), but it would give me an idea of the stumbling/backfire problem is from a lack of fuel. Took the car for a drive at night since it was cool enough not to need a fan and it actually ran a lot better!!! Ran very well under hard acceleration. A couple of questions for those with a bit more experience...when I am at a higher speed (mph) in a higher gear (4th or 5th) and very low throttle and RPM, say 1,200-1,400 there is still a noticeable miss and stumble. Not bad and not that often, every few seconds and just enough to notice if I am really paying attention....I know that the engine has high compression, don't ask how high, I don't know, but I cannot rotate the assemble by hand and I cannot push start the car (it just stops dead when the clutch is dropped) and I do not know if the engine has any cam at all....it is not radical, but when idling it does have a decent lope. Could this, slight stumble and miss at low throttle, be normal for this engine? Or should I continue to trouble shoot the ignition system? It is starting to run very well WOT, but we all know these cars cannot be driven that way regularly!!!!