It seems to me this was brought up in some thread here somewhere but the search terms are a little cumbersome.
We've experimented with a PCV valve that's simply a fixed orifice packaged in a traditional SBC valve. The principal being similar to that of an LS. The Holley EFI Monte Carlo uses one and it really helped to smooth out the tune.
I'm thinking similarly with my carbureted 357.
Who here has used one? And in what application?
I also like the Wagner adjustable valve although for the sake of experimentation, it's a little pricey. It has a fixed orifice mode designed for engines that generate poor idle vacuum.

The valve in the Monte is this version.
https://mewagner.com/?page_id=447

 

That is the "valve" from the GM TSB for the early LS engines. I have run them for years myself.

 

Interesting. Seems to me I've read that somewhere as well.
Do you have any feedback as to its functionality?
From a tuning standpoint, and keep in mind this is carbureted, I'd see an easier time of it with something static as opposed to something variable.
That said, I'm not having an issue per se, as even with the old wheezy engine, everything was reasonably well sorted. The blowby though was another matter. This is what led me down the PCV rabbit hole.
This latest engine is in the tuning phase (LOTS to do still) and if I can control one variable, so much the better.

The current layout is: Passenger side breather, drivers side valve to an oil separator (a carry over from the blowby engine) and then to the intake.

 

Are you more concerned with smoothing out the idle or blow-by?
IIRC, you mentioned a vacuum pump. Don't waste tons of time with this because the VP is most likely going to change everything and then you get to start over.

 

With the fresh engine, blowby is no longer an issue. The old engine being very worn was causing all sorts of weirdness but I did manage to tame it. That's where I got deep into ignition timing and vacuum advance. It's looking though like what worked for engine old isn't suitable for engine new.
I haven't gotten too deep into the new engine tune but one of things I'm considering is this fixed orifice valve just to eliminate that variable. Although with a sound and well sealed engine, that variable is reduced. I've always managed to get an OEM valve to work (I have a half dozen with different setpoints on hand) but having said that, I've read volumes on how there's room for improvement.
Which brings us to the vacuum pump. It's a performance orientated thing and as I understand it there are benefits to be gained.
But you're right on going in one direction (a different valve) and then introducing a pump. But the pump is a long ways off. It'll take a season or two at the track to determine what the rewards might be if I incorporated one.