You have just burn so much money to fix this problem but havent prevail, yet since all the changes and carburator overhauling this should bring your car in great shape!

Perhaps, not yet! The problem still there and disperately seeking help. Of course you dont want to burn a chunk of money to those money hungry mechanics and hear diff. story if they cant bring your car properly.

earthlykin, I was thinking the Cold Start Valve but not possible since this a carburated car. The only thing I can think of is your ignition system. You have changed the spark plug , overhauling your carburator but you havent change your Cap and Rotor and check also your spark plug wires for crack replaced it if nescessary. Check also your fuel pump relay if corroded, clean it or replace it. Good luck.