Thank you, all, Ezap, Sstef, and Trev29 for your insights. If you missed it, these restart problems happened after I modified the B21E Electronic Ignition with B21A Weights, Springs, and Vacuum Capsule. The Spark seemed weak yellow. I reverted back to my original Distributor that I carefully stored, with its Coil and Ballast Resistor, and flawless. Did my experiment fail or maybe something wrong with the B21E system. I checked the Ballast Resistor and Coil, and they were OK, so, I suspect the Inductance Coil or Reluctor, inside the B21E Distributor, but do not know, as I have not followed it up, yet.

Stef, on your website, I noticed your Vacuum Advance capsule, attached to the distributor. You have two hoses. Where does the one nearest the distributor (radiator side) attach and where does the one on the conical shaped part of it (carburetor side) attach?

My distributor has a single hose type of Vacuum Advance Capsule. I am guessing your is advance/retard type. What year is your car? I wonder why they would use a different Vacuum Advance Capsule, for the same engine, for different year models. Any ideas?

I changed Fuel Pumps, just in case. It seems, my old one was functioning ok, though I do not have a Fuel Pressure Gauge in my kit.

I will follow-up if this different Fuel Pump - Italian-made with internal filter improves restart problems. Vapor lock? I have not had this problem, before. My old B21E would just about blow the fuel filler cap out of my hand, when opening the tank. The B21A has no fuel tank pressure like the older B21E.

The Temperature Compersator on the Side of my Zenith-Stromberg Carb, the Center Screw was screwed all the way in. On the spare carb, the Temperature Compensator was not. Again, I wonder about these differences. I swapped the Temperature Compensators, but it seemed to make no difference. After, the restart problems I experienced months after I swapped them, I decided to swap back to my original, with the Screw all the way in, to see if that makes any difference in restart. I haven't had a 5 minute run to the shop, yet, so I do not know.

Thanks, again.