I believe that the only difference between ported vacuum and manifold vacuum
is at idle.
With ported vacumm, since the throttle plate is closed, there is little or no
vacuum
at the carb although there will be 15-20 inches at the manifold. However, at
higher revs,
the amount of vacuum is constant
Bill wrote: "...While I'm not an expert in vacuum dynamics, I would think in
this case that
vacuum is vacuum..."
With the proviso that I am not an expert on this area either, I do think
there is more to it than that. Based on vaguely recollected forum messages
I've read over the years, you get a
