6 Bowl vent to canister 8 venturi vacuum to egr valve system

So this means that at idle, there's a pretty good vacuum being applied to this tophat. Which means the air in the bowl section of the carb is exposed to a good vacuum at idle, way below atmospheric pressure.
This can not be right ,the filter at bottom of canister would have to be completely clogged.

If you don't have a canister, and you just plug the port on the throttle plate (leave the tophat port open) then is the carb designed for that? To have no vacuum in the tophat at idle? It may run and idle ok, but will it meter out the fuel as designed?
At idle bowl vented to canister or open to atmosphere is correct, earlier bbd carb only used internal vent to venturi, so blocked off will work too. At above idle vent should be closed, internal vent only to air pressure under air cleaner. If vent leaks atmospheric pressure to bowl carb will run rich.

I don't know how much resistance to airflow there is normally in the canister. So it might, or might not, be ok to connect a line from the canister throttle port directly to the tophat port? Or would that flow too much air?
Bad idea ,some of the first canister,s were vented to purge port at idle, lasted for short time, hard to set idle mixture. Carb heat some gas would boil evaporate out vent, idle mixture would go rich.

Yikes, no, don't do this. If you're not running a charcoal can, just leave the bowl vent open to the atmosphere. It will not adversely affect anything about the carb's metering.

If you want to read up on how (and why) to run a charcoal can, see here.

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Too many people who were born on third base actually believe they've hit a triple.

So none of these ports actually are intended to flow a stream of air into the carb. ?

Naturally any ports that are connected to a diaphram won't flow air (choke, distributor).

EGR port is also just a control port? It doesn't flow air?

PCV and Evap Canister sort-of flow air, but their air flow doesn't factor into how the carb controls fuel mixture?

The underside of the air cleaner housing has a small port/nipple coming off it, does that flow air into some carb port? Does the carb need that connection?

I've driven the car today with this dromodary carb, drove it to where the car is stored for the winter. I've adjusted it to idle slow, it runs ok when at a stop light, it accelerates ok, runs ok at 30 mph. I'm thinking the only way I'm going to know if it's set up correctly is to buy one of those tailpipe emission testers that check HC level to see if it's running rich or lean.

I disconnected the fuel line at the fuel pump, started it one last time, and was surprised how long it idled before it cut out. Probably 2 or 3 minutes.

Correct.



PCV flows air, metered by the PCV valve, which needs to be present and hooked up correctly, together with an appropriate crankcase breather.



Pic, please; that description could refer to a couple of different kinds of port.

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Too many people who were born on third base actually believe they've hit a triple.

Canister vacuum picture

One on each side, hole is small drill bit in hole above throttle plate at idle