Hello!, Thought I'd up date you guys on this rabbit I'm chasing. I went back to square one , reset the timing, checked the dwell, removed and cleaned the fuel line from the tank pickup to the carb, checked the valves ( they were all opening), tore the Carb down again, checked the ignition wiring etc.....the stumble is still with me. I have a couple of choices left...the heat control spring on the exhaust manifold may be my culprit, I was looking at it and looks like it has been modified, broken and re-bent. I had some help one day so maybe?? anyway, I an going to replace the vacuum advance (what could it hurt) and the spring to the manifold. I'll let you know...anything else you guys can think of?.