20* initial timing is too much. Where do you have the vacuum hose for the distributor hooked up ? It needs to be ported, not full manifold vacuum, sounds to me like you're running it off full vacuum. With ported vacuum, you do not need to disconnect the distributor to check the timing as the vacuum advance only sees vacuum with the throttle open. You do not need a stall converter with that cam.
Agreed, the 20* is too high. I haven't been driving it that way but I had to quit for the night last night. I'm going to drop it down to about 12 tonight. The mixture screws DO affect the idle some but not really the vacuum that I could see. I'll reset the timing and play with the idle until I'm satisfied it will hold until I upgrade the carburetor and intake. Thanks guys!
While it's highly likely that 20* of initial timing is too much for your carbs current tune.. it's no where near what that little smog motor will likely need to improve the efficiency of that ill concieved combustion chamber. Not to mention the poor quench characteristics that are only adding insult to injury. ALWAYS best to tune with a vacuume guage for best results.
I took the timing back down to 12* and adjusted my base idle to roughly 900 (sometimes it idles at 900, sometimes at 1000...sticky parts maybe?). It idles pretty good and a little rough (to be expected) in gear, and rougher yet with compressor on BUT I didn't get it to die yet. There's probably a certain degree of me not "knowing" this motor yet and what sounds like stumbling/about to die is really the rough idle of the cam. I'm still interested in the solenoid that can kick up RPM when compressor engages...where would I find more about that?
This is the high idle solenoid used in the '70s, there is also a "L" shaped bracket necessary that it mounts to on the carb... http://www.ebay.com/itm/New-69-71-7.../321273043304?pt=Vintage_Car_Truck_Parts_Acce
