[THE BEAST]

I have searched. Can anyone point me in the right direction ? Looking for a full explanation of SPECIFICALLY how the PCV system works on a N54. Also , besides holding boost, why are upgraded ones better ? Back to holding boost, how and where would they possibly leak ? Flapper valve function ? Ive read on people retaining this AND people removing them. Why ? Pros and cons ? Thanks in advance.

[Rob@RBTurbo]

PCV systems provide many benefits and they have been discussed probably thousands of times now on these N54 related forums. You can also use google to see the benefits of PCV, as to not have to take one or two persons word for it. Removing PCV system is not typically recommended without much other afterthought, which seems to be a common mistake in this platform.

Also PCV systems are not designed around high flow, which often confuses the masses as high flow has a nice "ring" to it in the aftermarket. The N54 operates with a closed pcv system and it does require the flapper assembly to remain intact as this is what provides the resistance to the slight "siphoning effect" from the PCV valve which resistance actually allows an actual minor vacuum to be created on the crankcase under most all low load operating conditions. When into boost the PCV system switches to ventilation only (ie. PCV valve closes and ideally resists all leakage of boost pressures into the crankcase while the flapper opens fully), while in OEM form simultaneously uses the rear (bank #2 turbo) inlet to provide some vacuum assistance.

Some links here:
http://www.n54tech.com/forums/showthread.php?t=35535
http://www.n54tech.com/forums/showthread.php?t=15382


Rob

[THE BEAST]

Thank you. Ill be calling you in a bit if you dont mind.