I just came back from the shop that works on my car and they said to connect hose that comes from valve cover back to the intake as it suppose to increse performace by getting rid of excessive pressure in valve cover. Cause when turbo spools it creates vacuum.

How true is this statement?? Any ides?

 

I can't remember, but doesn't it already do that? It's not vented to the intake for performance, it's for emissions IIRC. This oil vapor can potentially coat the turbo and intercooler, so a catch can installed on this line will allow the pressure to vent but keep the oil vapor contained.

 

Does it matter if it just vents to atmosphere and not back to intake?

 

I would just vent it to a catch can or air Alex