Breather tank/catch can/oil-air separator plumbing questions

[Super Roo]

Breather tank/catch can/oil-air separator plumbing questions

Hi all,

Sorry, yet more questions. So, one of the previous owners of my car fitted a breather tank. Just before I acquired it it was looked over and some of the plumbing changed by Unigroup in Sydney. Attached are photos to show how it's plumbed in. From my research on this forum (very useful as always, thank you all!) and comparing to stock engine bays, it looks like the two breathers at the back of the cam cover are as stock, and are linked on the passenger's side to one of the turbos as stock. On the driver's side it's linked to the breather tank instead of linking to a PCV valve or whatever that thing on the side of the engine is, which is now blanked off. Currently the tank vents to the atmosphere through a little filter.

The first aspect of this is I need to make it legal to pass rego. It only needs to be or look legal for 30mins, doesn't need to be an elegant solution. I tried blanking off the hose to the breather tank, but that either causes massive blow by or is pulling oil in large quantities from the top of the engine, as at idle it made piles of smoke. So I'm assuming the solutions are either to find a stock PCV valve and hose to connect onto the driver's side, or to take the filter out of the tank, hook that up to the pipe into the turbo, and blank off the passanger's side.

Secondly, I'm curious if this setup is actually done properly. What makes more sense and what a lot of people on threads here seem to have done is blank off the turbo inlet and hook the passanger's side vent into the breather tank after combining with the driver's side pipe. Otherwise surely the system is still going back into the inlet charge, which defeats the purpose?

Thank you very much for your help and time as always!

[KiwiRS4T]

As you say the vent is illegal. I (and I think most people) run the vent to the turbo intake. If you are spewing a lot of oil out the top so that oil is going into the turbo intake then you need another fix but the short term one would be to put another air/oil seperator into that line. Sorry I haven't read your earlier posts and don't know how necessary your catch can actually is. If you really need it have a read of at least say the last half of this thread to see what it is all about: