Hello My 1978 400ci have a Holley. Intake seems genuine ? So 4 pot on a genuine intake ? I was thinking the 400 have a 2 pot carb, so 2 pot intake ? The car hesitate between idling and driving. I've to go real slow on accelerator pedal or it dies. I've got a Cooper tube beside the carb, it seems to be a vacuum ? Does he have to be connected ? maybe 1/4 inch at the right of the serflex. I doesn't arrive to know what carb ref ?