Also, you may have an issue with your mechanical advance not quite returning back to fully closed when you turn the engine off, which would mean at cranking you are getting more timing that you need.
I had this issue on a 340, hot starts were embarrassing. I almost got stuck on a car ferry 'cause the friggin thing wouldnt start back up. Got it home and the dual point advance plate was corroded. Couple shots of WD-40 made it snappy again and didnt not have any future problems.
