Cameo Ivory 1967
I run mine off the intake and sometimes at Cruise my vacuum gets up in the high twentiesMost Pontiacs were set up originally with manifold vacuum to the advance on the distributor. This gave a cooler running engine at low and idle speeds and good advance at cruise speeds where the intake manifold vacuum is still high. I have always run manifold vacuum on my first-gen GTO's, as set-up from the factory. Some engines seem to prefer ported vacuum, though.