Why could you not use a PVC that connects in line with the hose? I know there are engines that use a PVC that screwed into the base of the carb with a hose running to the valve cover.
A 90* fitting in the valley cover short enough to clear the intake to connect to the PVC and then on to a carb should work.

LOL, I plead guilty and I know better.. I call the PVC like most people, but when researching a bit I rediscover that they are PCV valves and really have nothing to do with polution control. They are for crankcase ventilation. Positive Crankcase Ventilation (PCV)
Dave

Doing a little searching I came across this as an idea.
https://www.ebay.com/itm/Brake-Booster-Fitting-For-Vacuum-Pumps-3-8th-Inch-Hose-Unpolished-USA/202587184650?hash=item2f2b231e0a:g:OEUAAOSwVFlT3Zfs

Use this fitting (or one like it) in the valley pan, connect a hose from it to a pcv then hose from pcv to carb.
Problem solved.

Dave

How do I plumb the PVC line into three Holley 94s?  There are ports in the manifold under full vacuum. 

You would need to drill and tap the manifold for a vacuum fitting or use a spacer with a vacuum fitting.  The ideal location for that is the center carb.



Lawrenceville, GA

If You are already tight for space height wise a Spacer won't work. Drill and Tap is the other Option.

  

I had an issue with finding extra
Vacuum ports for my trips setup.
I needed 4- ports. 1- brake booster.
2- pcv. 3- trans.4- distributor. I used
The port under ctr. And front carb.
I made a 4- way port of 1/2" copper
Very easy to solder....

Dave C. It's not quite correct to say  a PCV setup has nothing to do with pollution control.  Along with providing  positive crankcase venting, it recirculates fumes thru the engines intake system, rather than venting them directly to the atmosphere..  


Paul

As "Mark" suggested, check to see if it's feasible to put a passenger car lower crank case breather canister or similar setup on the left side of  the block? U might have to shorten the downtube somewhat, maybe .? Or would it be feasible to grind the intake slightly to fit ?.. A PVC setup would be good normally, but with your 3 carb setup. it could get complicated.. 
P.S.- obviously Edelbrock never intended their Intake to be installed on Birds.. 


Paul

The biggest problem with running trips on a '55 TBird is hood clearance.  I was able to get them to work with screens in the carbs.  Most air cleaners wouldn't fit.

My 56 is a factory open system. After driving in the garage it did have an oil odor. At idle at a signal I could also smell it. I put an oil breather cap with a 1/2” hose fitting on it and the other end into the bottom of the air cleaner with a 90* PVC fitting aiming at the front of the carb. No more smell and the side breather is still there is never wet or drips. I clean it at every oil change.
I’m sure I’m helping the environment.

56 Vic, B'Ville 200 MPH Club Member, So Cal.