so after it sat for that long did you rebuild the carb? that may be a good idea, I have never let a car or truck carb sit that long but I had that same problem on a motorcylcle I had after sitting through a winter. I rebuilt the carb and replaced the fuel filter and it was back to normal, sounds like your problem resides either there or in your timing. where did you set it to? I know my manual calls for something like 10 degrees before TDC.