KB, It's all in the thread but to recap:
Both Chad and I are using OEM Subaru shortblocks. Mine is new.
Chad has three active and passive oil coolers on his! I have one that is airflow only. It worked great on my wet sump setup, almost too cool.
OEM at 600 rpm idle the specs calls for 14 psi. When mine gets really hot, 230+, they do drop to 8 at idle. I'm going to increase my idle rpm to cure that.
Chad has his on his 818R, mine is on my LGT. So my radiator setup is very different from an 818. It's a Fluidyne radiator with two Spal fans. I really don't need the fans except for tests like this. At the racetrack the only time I've had water temps high enough to turn them on is when waiting in the scales line after a race.
And your question about what happens when the oil filler cap is opened: I have removed the fill tube and dipstick, replacing them with a block off plate. That leaves more room for -12AN lines coming and going to the DS Pump.


Next up is running some tests with a vacuum/boost gauge to see what happens if I leave the engine sealed up; if too much blow-by is not scavenged and creates a positive pressure in the vent tubes. I can't really test that until I get to a track and get the car under load so the turbo will boost. I don't really care if it's creating vacuum, I just want it to keep up with blow-by pressure. If it does I may just leave the system sealed up, effectively running two balance systems, the OEM on the back vents and the 3/4" hoses on the front vents/pcv vent.