i have a 1937 Plymouth that now has a 72-74 Dodge Slant Six 225. It has an Offenhauser dual manifold with 2 x 1 bbl carbs. I think they may be Holly 1904 as there are no markings on them. The engine starts fine and idles good too. However, as soon as you give some gas...it bogs down, studders, no power to even get up a car ramp. then it stalls out. I am think it only does this in drive !!!...
Today, i noticed that the previous owner blocked off one side of the PCV (was broken off and plugged) and of course no hose connected to it. There is a cannister and it has one port with nothing on it. Assuming when i get a new PCV this it where it would go...looking for directions...or diagram.
The other ports has a hose from the vent of the gas tank. One goes to the rear carb bottom. On the other front carb, one hose from canister to bottom of carb and another vaccum line from the distributor advance. I have no power brake booster.

i just oredered all new vaccum lines, plug wires, cap, rotor, and plugs plus a coil. but thought i would see if there is something to do before i swap out the new stuff.

Can you post a couple pics of your carb(s)? Get in a little close, so we can see some detail. One issue you may be having, (if it's 1904's), is that they don't have a ported vacuum source, and the slant needs a ported source. Having engine vac at idle is not a good thing for the Mopar distributor. (And that "power valve" screwed into the base casting isn't a power valve.)

Waiting for pics.....Roger

Also pics of that canister you mention, please, and pics of your valve cover showing your oil cap and whatever other breathers, caps, hoses, valves, etc might connect to it.

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