Why Won't My Carburetor Suck?

[Eagle43]

I have a 52 F1 with an 8BA V8. For some reason I can't get any vacuum from the vacuum port on the Holley 94 so consequently I don't get any spark advance. I have a hard line from the carburetor to the spark advance and checking with a vacuum gauge I get absolutely nothing. I've had the carburetor apart and gave it a thorough cleaning and blown through the port and it's clear. I get about 17 at the intake manifold. Its got me stumped. Any help would be much appreciated.