Allumeur CSI MG B moteur préparé LUCAS 23D sans dépression
Allumeur CSI MGB remplace 25D avec dépression POSITIF à la MASSE
This "Pigtail" wire is all that carries current through the distributor to the points.
The stock vacuum advance distributor is connected to the carb/manifold by a small rubber joint that in turn is mated to metal line that fits the distributor. If the little rubber connector is deteriorated it could allow a vaccum leak at the carb and stop the advance from working properly. The rubber connector has a 90 degree bend. When in doubt, replace it.