If I understand correctly, the actual vacuum (negative pressure) in the system is the same, with factory CCV or without.
By factory, the CCV system simply blocked the manifold suction, so that the CCV Valve was controlling the flow basically, and not letting manifold intake pull at full force.
Without the CCV, intake manifold creates a lot stronger pressure because there's nothing stopping it.
So now the negative pressure must be trying to pull air into the engine from anywhere it can, like all the gaskets and seals. I guess they can't really leak, cuz the negative pressure is so high. How can oil leak outside if it's beong pulled inside? Yet at the same time, it must not be great for these gaskets and seals to be under so much pressure, they can probably get damaged by constantly being pulled inside the engine.
I'm not an expert and don't know for sure how it works.
By installing the PCV valve between valve cover and manifold, does it not restrict how much air the manifold can pull front the valve cover?
Or otherwise what's the point of that pcv valve?