Triumph Repair: vacuum advance, weber DGV DGAV vacuum

Question
The car is a 1979 Spitfire 1500. It has electronic ignition,and a Weber carb conversion. There is a place to hook up a vacuum tube to the distributor, but I can't find a place to connect the other end of the tube. I think it should be connected to the intake manifold.

   Thanks, jan

Answer
On a weber DGV, there is a brass tube along the base that connects to a hole in the carb body on the intake manifold side of the butterfly valve.  If you have compressed air, you can use that to find out where the various tube connectors come out on the carb body.  There are several brass tube connectors on a DGV series, and since not all DGAVs were made the same, that vacuum tap may be one of several different connection points.

On some versions of the DGV/DGAV/DGEV, this connector is plugged with a lead ball, other's with a small rubber cap.

Most pierce or cannon intake manifolds also have a flat disc on the top side of the manifold that could be drilled and tapped for a 1/8 NPT to hose barb fitting.  

FInding the tube on the base of the carb is the preferred choice, as then you aren't modifying the manifold.