Apologies to the Mod's if this should be in the electrics section. Kind of a nexus I guess. Anyway after diving down the PCV rabbit hole (still not fixed) I heard that older american dizzies like a full manifold vacuum signal at idle, not ported vacuum as Holley's have. Can anyone tell me if the standard Lucas likes ported or manifold vacuum? Mine has been converted to lumenition but I suspect the vacuum advance is original spec.