[Putershark]

That still sounds air / fuel related to me.. I would drain off the fuel inside the carb bowl and make sure that the float in the bowl is set correct (most are set to be level when the bowl is off and looking at the float) for it sounds as if the float is not letting in "enough" fuel (or it has junk in it) before the bowl goes dry.

I would also use some throttle body cleaner and make sure that all the idle air bleeds and the carb is clean

Also make sure that all the bolts for the carb and intake manifold are sung.I would also make sure that you are not dealing with either a cracked vacuum line or a spark plug wire that is grounding out...

Let us know how you make out