[Bruce Meyer]

Sounds like carb is lean under load to me.

[mgarblik]

Just remember 90% of all carburetor problems are ignition. (from my mentor, 50 years ago). It's a joke, but some truth to it. No idea who the "professional" was that did the carburetor work, but for now, lets assume it was done correctly. I say this because we know the distributor is NOT correct. It should not have light tension, silver springs on it. You can try a couple things just to see what difference it makes. If you have an old distributor laying around or have access to one with factory springs, put them in and see what happens. Also try changing full manifold vacuum for the VA to ported and see what happens. That should tell you something. Ideally, pull the distributor and have it re-curved by one of the guys on here with a distributor machine and the necessary tuning parts.