Engine Idle Shake
I don't know what cam, engine was already together I never pulled it apart. I did change out the spark plugs, no change. The RPM is at 1000 when I measure initial timing.
What did they look like? That's always useful to check.
What else can you observe? Smell the exhaust, listen to the engine - these are all clues - even if they mean little right now.
Some specific suggestions.
When it 'warms up' is this when the choke fully opens (it is opening, yes?) or when the coolant termperature opens the thermostate (around 180 F)?
If its the initial, it could be the choke opening too quick for the situation.
If its in the coolant and oil up to operating termperatures, then maybe lifters or something. Using a vacuum gage onto the manifold vacuum port of the Holley will show how strong its pulling and if there are variations (pulsing) due to misfires.
As far as the drop in rpm placing it into gear - its probably too lean and too far advanced.
It could be a deteriorated vacuum cap or PCV hose or something like that. It could also be dirt of varnish in the carb.
Before blathering on, its worth mentioning that most distributors are set up to start advancing around 600 to 700 rpm. So keep in mind that while you measured 20* BTC at 1000 rpm, at 700 rpm its probably less than 20*.
See if you can get the engine to idle at lower rpm in neutral by richening the idle with the mixture screws, and then slightly reducing the idle speed screw.
Then try it in gear.
If the mix screws have no effect, then either the throttle at idle is too open, or the passages are blocked with dirt/varnish, or the fuel level is off - probaly too high and fuel is dribbling out the boosters.
