With 8 valve Turbos, I allow the crank case pressure to exit unrestricted through a large hose.

If you block the crank case vent line, the engine will most certainly leak past seals etc.!!

Pressure builds in the crank case naturally, blow by is the main contributor, it can not be contained, and trying to contain it can result in leaking seals !! This pressure doesn't need to be taken, its going !!

This pressure vapor contains moisture, and assorted by products of combustion, all octane reducing, and its going somewhere!!

Where it goes is up to you. Straight out to the atmosphere, or air box, or PCV, engine air intake etc., your choice.

Any restriction to natural flow can create a venturi effect that can even suck liquid oil. Any oil that collects in the intercooler, etc, is oil that was snatched from the crankcase breather and rerouted to the engine air intake, as in vacuum.


Thanks
Randy