opened up the tank and mounted a plate the length of the container to seperate it then it is vented through another two holes that have filters off them. So the tank has 4 fittings.

oh! awesome thanks :)

Thread revival...
Would I be right in thinking the catch can should be big, baffled, perhaps packed with steel wool, sealed, and plumbed back to intake?
What would be the outcome on a gen 2 turbo if it was NOT plumbed back and open/vented? Loss of metered air? Boost leak?

Being open to the atmosphere will have no affect on the motor, aslong as the port on the intake pipe between the turbo and AFM is blocked.
 
If its plumbed back into the intake (pre turbo) then obviously baffles will be required and it will have to be sealed.
 
If its open to the atmosphere then baffles arnt required but may help with oil mist in engine bay
 
The bigger the better realy, keep the hoses and all the fittings the same size or larger than the factory one / L pipe on valve cover, the better the baffle design and number of baffles obviously will work better.
 
Some people may put a drain from the bottom of it back into the sump, most just have a drain bolt on the bottom and check it every now and again and drain it.
 
For CAMS events, if its open to the atmosphere it shall have a 2L capacity, for up to 2L motors and 3L capacity for motors over 2L.
2L is much bigger than most ebay cans, and 3L is huge! i have a 3L but only spot it would fit is the boot!

My opinion, I think fitting an atmo venting can on an AFM car will make some difference to idle quality etc, have you ever tried pulling the oil cap off whilst the car is running, it idles rough, at least from memory when I did this about 10+ years ago.  Also, don't drain an atmo venting can back to the sump.  There was an atmo venting can on my Exige and when I opened it it was full of sludge due to moisture ingress mixing with oil vapours.  It was filthy, its not something I'd want draining back to the sump  The can was setup to drain back to the sump but I quickly changed it.  It was a **** ebay can, non baffled etc, so I ended up making up two of my own baffled, sealed cans and returning the PCV setup to service.  I'll see if much oil gets through, though the cans are fairly well baffled, make use of centrifugal seperation and also have some filter medium after the last baffled, so it should be fairly minimal.

I have a drain back into the sump. Water isn't an issue as I change the oil regularly anyway - race car.
With the drain in place, I never have to empty the can. Win. I have a small filter that allows the can to vent to atmosphere. I also have a secondary release valve (a dodgy one) with holes drilled in the top of the catch can with race tape over them. If the small filter ever blocks with pressure building up, the race tape will give way and let the pressure out.
You don't want oil mist going back into the intake because it will increase the possibility of pre-ignition - this is particularly important on a turbo race car.

You never clean your can Glenn?  Have you ever opened it up?  My drain back can probably wouldn't have drained back anyway, was clogged up with curdled looking sludge... Lemme try find a picture.
 
Here we go:

 
I have subsequently fabricated and fitted these to retain PCV evacuation:
Baffled design:

Complete:

Fitted:

 

I'll clean it when the engine manages to stay together for more than a couple of hundred Kms