catch can am i right?

[Vteckidd]

But the PCV only open under direct presure to release blow by,so if its always open it creates thesame effect..

i think you just answered your own question lol.

The PCV only opens when there is POSITIVE PRESSURE on the spring inside the valve. When it gets pressure it opens an releases crankcase pressuer an gasses. If you eliminate that valve an its ALWAYS shut you can create lots of stress on the Crankshaft an rotating assemlby as too much positive pressure in the crank case can cause devastating effects. Leaving it open all the time can cause negative effects as well as their needs to be some pressure inside the crankcase.

the original design behnid the Catch Can was to catch those oily gases an keep them from going into the intake manifold an "gummng" it up. It was to keep the intake manifold clean. Nowadays, ESPECIALLY in NA cars, there have been great strides toward power making catch cans. the slash cuts is one of those ideas.