Is there a difference? I'm a carb newbie and I'm trying to reconnect all my vacuum lines. Here's the setup I'm going to go with, please correct me if this is wrong.

Distributor - Carb Vacuum
PCV - Carb Vacuum
Brake Booster - Intake Vacuum
Transmission Vac - Intake Vacuum

Thanks in advance guys.

 

I use the lower carb vac for the trans. If I had dizzy vac I would run that on the upper carb vac(ported). The other two are fine IMO. I'm refering to Holley, Not sure about Q jet.
Mark.

 

To be more specific:

Carb "timed" or "ported" vacuum - above the throttle plates, therefore no vacuum until throttle opened above idle.

Carb "full" vacuum - below the throttle plates, therefore same vacuum as the intake plenum. Usually from one venturi only.

Carb "plate" vacuum - usually a larger port in the throttle plate, between primary or secondary venturi.

Manifold plenum vacuum - below the carburetor, in the plenum and therefore fed by all cylinders.

Manifold runner vacuum - on a particular cylinder's vacuum, therefore not fully fed by all cylinders.

"Timed" vacuum was used primarily for emissions control, such as vacuum advance, EGR valve, etc.

"Full" vacuum was the pre-emissions hook-up for vacuum advance.

"Plate" vacuum usually used for a vacuum device that has a small amount of flow, like the PCV valve. Used by the factory on q-jets for the brake vacuum power booster.

"Plenum" vacuum rarely used by the factory, sometimes used as a replacement for plate vacuum when a carb doesn't have that port available.

"Runner" vacuum used for non-flow devices like transmission vacuum modulator, HVAC control, etc.