Pulling V.A at idle

Ironracer said
Well, it's a Holley 3310, 750 vac sec... port is on passenger side, high up, almost level to the Sight plug....

Then somethin's "wrong". Where is your initial timing? If it's too low and you have the carburetor idled up to compensate, you may be pulling vacuum from that port when you're not supposed to be.