Low vacuum pressure (3")

Looks like you're in "the green".

 

Yes, when I plugged that nipple off and went to check brakes, they were still pretty stiff. I unplugged the hose from the manifold to the booster and a sorta hissing noise went away. I put the plug back in or even just on without pushing in and I hear that noise again. I have looked everywhere and tried using my hands to try and get a change by grabbing and covering different areas. Any clue? Seems like the noise is further up towards the distributor

 

This is not allowing me to upload the video. "Security error occured"

 

No video.
Trace down every rubber hose coming from the carb and intake manifold to wherever it goes. Sounds like you still have a leak or bad hose connection. But you are almost finished. You could still have a bad diaphragm inside the brake booster itself.

 

Video

Thanks for the advice guys. I will keep searching. The booster is brand new and replacing another one that was newer. I I purchased it with 4 drum brakes and a hard pedal. He has just replaced the booster and gave me a line. This was my lesson learned slow down and bring someone who knows purchase! Lol. "Education is expensive" I had the wilwood double piston front disc brakes, tubular control arms top and bottom and coil overs front and back done recently. It didn't correct the issue and the tech said he tested both boosters.

 

Cut off the bad end. Have a new hose and pcv coming Monday.

 

I can always use a spare. I figured going through these items and tuning it up while waiting for a 4bbl intake to be found will help also familiarizing myself with the car.

 

The Q-Jet will make a sucking sound at idle, you sure that's not what your hearing?

 

Does the one photo above show a disconnected hose in the rear by the carb manifold port?
It looks like it's a disconnected hose.