I don't think you really read Beaner's post very well. What you just described is his "When you put the breather on one end of the big hole and the vacuum on the other all you are evacuating is the big hole." analogy. All that is being evacuated is the 1 valve cover. I'm sure it would relieve pressure and prevent excess crankcase pressure from blowing out gaskets and seals, but it's not ideal. Better is installing the pcv in one valve cover and the fresh air inlet in the other.
The best approach might be to look closely at how well a given PCV system works. If you pull the oil fill cap or a valve cover and see the dreaded "chocolate milkshake" residue then there's still some moisture trapped in the crankcase. Either the existing PCV system isn't working properly (bad valve, collapsed or split hoses or plugged up breather filter) or your home-built vent system needs a little rethinking. This is a more common problem for stop and go and short haul driven engines.
Obviously my plan is not ideal but i am hoping that it gets close enough to work better than just venting the lifter valley. I have a vintage NOS Fenton Manifold and Fenton valve covers. Both are pristine and I do not want to drill either one. I am using a mid 60s Corvette oil fill with a non-vented cap and the PCV in the tube which is connected to the carb base. I made sure to use the correct PCV valve for it flowing the correct way. I drilled and tapped the fuel pump housing and put a small filter on it. This keeps it away from the oil sling and somewhat hides the filter at the bottom of the motor. I know it does not vent the entire crankcase but with it being so close to the crankcase I am hoping it will get the job done. I have not tried this yet as the motor is not running nor installed in the car.
If your engine is in good condition your setup will work fine. A PCV and vent cannot cure leaking compression poor condition engines that have excessive blowby.
Several folks mentioned using a pcv valve matched to the engine size and performance type, and that makes sense to me as a hipo engine with a big cam has less vacuum that a stock grocery getter. But when I started researching listings for pcv valves for sbc, and IIRC, it was in AC listings, all the sbc engines with a push in pcv valve sized to fit my valve cover rubber grommet, the factory catalog showed all the different models and engine ratings, etc. But they all had the same part number for the replacement. BTW, I'm using a '73 350 block, 2X4 rpm air gap Edel intake manifold with no provision for oil fill tube, pvc valve in right valve cover hole and small K&N type breather in the left. Have to fill with oil by pulling rubber grommet, and slowly fill thru the hole, unless it's also valve adjustment time (solid lifters). But I agree with the concept of cross ventilation, and you get that with this setup.
Have anyone ever looked at a Y block ford. In 1963 the factory installed a PCV on them. They used a plate to cover the crankcase breather hole on the side of the engine block. The oil fill was in the front of the valley pan and about 8 inches back on the same valley pan was the hole & grommet for the PCV valve. The valve covers where solid without any holes. A PCV no matter what the design isn't a cure for condensation and milky residue that you get from driving short stop & go trips where the engine never really warms up. If you drive short hops you gotta change the oil a lot.
"...... electricity will follow the path of least resistance. " Small point. If that were strictly true, everytime I turned on the headlights the engine would stop.
Yes, it is true that the OEM's have progressed with crankcase ventilation over time, just as they have with the rest of the engine design, and the rest of the car as well. Look, no sense arguing about it, if you have your mind made up already than no amount of reason will change it, that's OK. It's a big forum with room for everyone. If all you can do with your setup is to ventilate the oil fill tube alone, or 1 valve cover alone, go with it. Whatever. Hell, don't run a pcv at all, it's your car, do it however you want. Ultimately, the point is to provide some way for excess pressure in the crankcase to escape so it doesn't force it's way out past seals and gaskets. Screw it, leave the damn fill cap off and run it that way. It's your car, I really don't care what you do. There are folks though that read these threads looking for information on how to do things correctly. With them in mind, on a V engine, the best pcv system is a closed system that places the pcv valve in one valve cover, drawing from manifold vacuum, and the fresh air inlet in the other valve cover drawing from the air cleaner housing. It's a closed system, air entering the engine is filtered via the air filter element, reducing contamination in the oil, crankcase gasses (and any oil droplets) are all consumed via the intake and not vented to the atmosphere. Is that absolutely necessary? No, see the above. Hell, in my hot rod I'm running an open system at this time. I plan on eventually modifying it to a closed system, but I have plans on modifying the intake system first and am not going to worry about it till them. Geeez, sometimes these threads sure get ridiculous.
I agree that the closed pcv system is better than the open system I have now, although I did try to at least filter the air going in thru valve cover opening with a K&N type filter. But awhile back, after a lot of thought, I placed on the "round tuit" list to make a hole in the bottom plate of the Edel unitized K&N type air filter for both of the 2X4 carbs, and add a nipple whereby I could put the vent inside the air filter to better control fumes during times when crankcase pressure might exceed the vacuum/volume from the intake manifold. But I still say valve cover to valve cover cross ventilation is better in a V type engine.
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