66, 250 finally have points adjusted to where engine runs smoothly, idle is around 900 rpm with vac advance connected. for some reason if i drive very far at all when i shut the engine off it diesels (i.e. wants to keep running then a loud whoosh noise comes through the carb) before it finally shuts off. any thoughts?
Timing !!! and probably a tweak on the carb adjustment too.... Drag out the tach & dwell meter !!! dv
Dang dv, you beat me to the punch. I'm thinking timing too. Another possible cause would be running the wrong temperature spark plugs. Are you running gasoline with an ethanol blend? That would contribute to the dieseling effects due to the fact that the "alcohol" vaporizes at a lower temp than the gasoline and is easily combusted.