You asked about the threaded one on the choke that is for a heat tube as vacuum is drawn through that to make the choke work. See pic, the one arrow is vacuum for the choke and the two arrow is ported vacuum for the dist if that is what you need. The reason tehse didn't have vacuum ports is because on older fords the pcv valve hook up was drilled right into the manifold. So they only needed the two I have pointed out.
Monday, October 21st, 2013 AT 3:56 PM