I was thinking of throwing a catchcan setup on the WRX soon, even though i already have close to 1/4mil miles.
did you fabricate it or start with a kit?
1st off, AIG, Crawford, KillerB, Radium Engineering ... they all make self draining , dual stage Air Oil Seperators. They are very expensive, over $300
I didn't make mine from scratch, although you could. I bought 2 catch cans. The 1st was a baffled AVO
and it was expensive at the time $140. I though one can would catch all the vapor. It was be fore I understood the system. I have since found simple Cusco
cans for $35. $35 is pretty cheap for a can with fittings. It would cost maybe $20 to replicate from the home depot plumbing section.
3" PVC tube
(2) end caps
You could do it that way.
Anyway with (2) cans, purchased or made, the real key is the plumbing. Radium Engineering conveniently posts a diagram on their website showing hows their's works. It's dual stage, for both sides of PCV operation. I just spit each operation to a separate can.
Both of mine have drain ports to remove, the "removed oil". The closed throttle (idle) side collect far more oil than throttling.