Originally Posted by TrickTurbo

If pcv and check valve are in place.
While not in boost you are grabbing filtered air through the engine. No big deal.
While in boost the turbo is now pulling harder and your crank case vapors are going to the turbo. Since your check valve is closed.

If installing this way you will want a oil trap of some kind in that line as well.
This type would be for 600 or less.

Our standard stuff comes with a check valve and a filter for that passenger side valve cover.