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I acquired a different set of valve covers for my 283 yesterday. They are cast aluminum Edelbrock covers, replacing a dingy aftermarket pair. The set I’m discarding has the common setup of breather on one side, oil fill on the other. The Edelbrocks lack the oil fill. (There is a knock out for oil fill.)
My question: assuming there was venting at the oil fill , is it ok for the that side with no opening to not be able to “breath”? And while I’m at it, if I am correct in thinking that the breather ventilates the crankcase, how is the crankcase vented to the valve chamber? Is it only vented to that passenger side? Also- how is the oil supply or level in that valve chamber regulated? What keeps that area from over-filling?
These are things I wonder about as I stare into the engine with valve covers and intake manifold removed.

When you received your "new" Edelbrock intake manifold, is it a new style with no oil filler tube accommodation? if so, you will need a valve cover with an oil fill and breather hole. The PCV will work with either set-up but your manifold probably has no oil fill hole. The heads have oil drain passages that circulate the PCV air flow.

The passenger side valve cover has a breather hole. It gets plumbed to the base of the carburetor. The manifold (pictured) does not have an oil fill accommodation. I have the option of filling through a funnel in the breather hole, or knocking out a filler hole in the driver’s side cover. It appears that it is cast for that option.

Nope- - - -that will create a massive vacuum leak and the engine won't idle. The beer can shaped device at the back of the valve valley connects to the cone shaped fixture beside the distributor, which is connected to the manifold with a PCV valve with hose nipples on it inline. The grommet in the valve cover needs to have a breather cap plugged into it, with either a filter or a hose nipple that connects to the "clean" side of the air filter. That's also the oil fill by pulling the breather cap out of the grommet. The device back by the distributor was where the road draft tube attached on older SBC engines.
Jerry

Ok , there is a fitting for that on the underside of my air cleaner.
Note the picture of the fitting on the hose that connected to my valve cover. Is that a PCV valve?

The connection for the beer shaped device in the valve valley is shown in the image withe the beer can , correct?

OK, you're almost there. The angle fitting on the rear of the block will rout to the base of the carburetor, it has to be manifold vacuum and is typically the largest nipple on the carb. Somewhere in the hose that connects those two locations, you will add an inline PCV valve. The 90 degree PCV valve that you currently have will not be used in this application. You could try to remove the guts of that valve and use it just as an angle fitting for the valve cover and that hose will go to the bottom of the air cleaner. Oil fill will be at the valve cover grommet via a funnel. You could try a Standard Motor Products # V329, or a Fram # FV266, or a Beck-Arnley #045-0299 as a PCV valve.

One other thing that may be a "no go", the valve cover bolt pattern might not match, it depends on the heads that are currently on your 283, if they are the original heads from '57, the new style Edelbrock covers won't fit. Check that out before you proceed with any PCV modifications. Small block heads from '55 through '58 or '59 use bolt patterns that are offset, later heads will have the bolt hole directly across from each other.

My 283 is a ‘67 , based on my research.
I’m not at the shop now, but I’m pretty sure that the heads and “new” valve covers are both opposite, not offset.

As to routing for that breather, there is a large threaded hole in the back of the base of the carb; it is presently providing vacuum to the brake booster.
Pictured is a large nipple in the front base of the carb - that is where the breather was routed from the valve cover. It would be a long way around, but should that be the connecting point for the recommended breather?

Btw, one of the reasons I never thought twice about that breather routing is because it had a nicely preformed hose.
Sure looked like it belonged there.

Addendum: Upon further review, I might better off routing the brakes to that front nipple; it would make a neat loop of the breather by routing that to the rear base of the carb.

If that larger nipple on the front of the carb is manifold vacuum, which I think it is, then either the brakes or the PCV could go there. Turn the carburetor upside down and trace that nipple and its passageway and see if it goes straight through the base of the carb underneath the throttle butterflies, if so, it's manifold vacuum. You could then research a normal old style threaded PCV valve to fit the rear port and run a hose from there to the rear of the engine block. Then the hose from the valve cover to the base of the air cleaner. The threaded port on the rear would probably be 3/8" pipe thread but you'll want to confirm that. Several PCV valves came up on a search that have male thread x hose barb.

Edelbrock does have information available about what the ports are intended for. Center port is for PCV

Not For Fuel! That's funny. I wonder how many people have hooked up the fuel line there?

That graphic is excellent, thank you.
So my PCV will go to the front.

Thank you 32vsnake for that illustration, very helpful.

Yet another question :
My transmission modulator has been connected to the small manifold vacuum port shown above on the right. It seemed to function well. My distributor advance was connected to the left side; I cannot say if it functioned from that source.
The illustration clearly states that the distributor should go to the right side on my non-emissions controlled 283.
That said, will my TH350 function if connected to the timed vacuum port on the left?

(Note: my vac advance functioned well when bench tested.)

I'm pretty sure that the TH350 wants manifold vacuum, you could easily tee into one of the lines for more vacuum points. HRL should be able to enlighten us on the tranny modulator but I think I remember them using manifold vacuum.

Standing by for Hot Rod ᠁.

I’m not Hot rod nor did I stay at a holiday inn last night᠁. Transmission modulator should have full manifold vacuum.

On your intake manifold it would generally come from the threaded boss just behind the carb mounting flange on the distributor side of the manifold.

I used the threaded port just behind the carburetor for my PCV connection.

In my case I am using a Holley carburetor so I do not have all of the ports offered on the Edelbrock but I do have a manifold vacuum port at the rear of the carburetor that I am using for my brake booster.

Looking at the valve covers pictures you provided you are going to need to add a hole with a hose plumbed to your air cleaner to provide air into the crankcase unless you engine has a different air inlet. The one existing hole appears to be sized for a PCV valve, or could have a grommet installed that would work with a PCV valve. That opening is not the greatest for oil fill given its small size but it would work.

Ditto on the full manifold vacuum for the modulator! The modulator serves the same purpose as mechanical throttle linkage on other transmissions- - - -the further open the throttle goes, the higher the modulator pressure goes in the transmission. Low manifold vacuum = high TV pressure. This determines shift points and timing of the shifting, also how firm the shift is. An automatic trans does a balancing act between three different pressures- - - main line, throttle pressure, and governor pressure (driveshaft speed).
Jerry

Guys , take a look at the provided picture of my “new”manifold. See the threaded hole aft of the carb mount. That port was as used for my vacuum wipers with the old manifold, and I planned to use it for that same purpose with this one.
Could I -
a) install a t-connection and plumb to both the transmission and wipers to that port without compromising trans function , or
b) run the wipers off of the timed port on the front of the carb, leaving the one on the manifold dedicated to the transmission, or
c) run wipers and vac advance off of the manifold vac port on the front of the carb , leaving the manifold port dedicated to transmission

What is the best option between the three proposals?
I am tempted to connect the wipers to the timed port on the carburetor because that would eliminate any tee connections, and I never use the wipers anyway so if that function is compromised it’s no loss.

Just to be sure, I turned the carb over and confirmed- it is manifold vacuum.

I wouldn't use the "timed port vacuum" for any of your items. If you have no need for the windshield wipers and only need a location to "park" the vacuum hose then you could go that route. The threaded hole in the manifold, the threaded hole in the rear of the carb, and the large low nipple on the front of the carb are all manifold vacuum along with the small nipple labeled manifold vacuum. The typical factory plumbing would have been: brake booster to the rear carburetor, transmission to the manifold threaded hole, PCV to the front nipple on the carburetor, distributor advance to the manifold vacuum small nipple on the front of the carburetor. I have no experience with vacuum wiper plumbing so in your case I would tee at the manifold threaded port for tranny and wipers. Then all you need is a hose fitting to fit snuggly in the valve cover grommet and a hose from there to the base of the air cleaner.

That is a very good summary. The only thing to decide is where to go with wipers , and that is minor.

To clarify: no PCV valve in the hose from the valve cover to the air cleaner, correct?

The hose from the air cleaner to the fill cap is the air inlet to the crankcase- - - -no PCV there. The PCV goes between the port beside the distributor and the intake manifold. Most of them will have an arrow indicating direction of flow- - - -the arrow points toward manifold vacuum.
Jerry

Thank you for that clarification.
Much of my vacuum plumbing was incorrect. Now I know what to do. I have high hopes that those corrections, combined with the swap to a more appropriate manifold , will result in a noticeable improvement in low end performance.

Then there’s the satisfaction of knowing that those systems are done right. I’ve learned a lot in the past few days.