i had a td05 20g fitted to my 06 sti and found that car was using more oil than before and was told from quite a few people that the engine breathes a little heavier with the 20g, so i fitted a catch tank to crank breather and have been running for a month or so with it. i have kept an eye on it since fitting it and not had a drop of oil in tank but have needed to top up oil not by much though.
so now im puzzled anyone having same issue or any ideas

cheers

 

I've got the same set up and only notice oil in the catch tank (just showing on sight tube) after a heavy couple of weeks up and down motorways, otherwise build up is pretty low.

 

Your catch tank needs to be plumbed to the cam cover breathers as well. If these still feed to the induction system, the engine will still be ingesting the crankcase fumes.

JohnD

 

John,
I've never seen any oil coming from the cam breathers. Oil build up in the IC and inside the turbo inlet pipe has steadily increased as I modded the 06 STi.
Just plumbing the +ve pressure PCV outlet to a catch tank has virtually stopped any oil build up - so I felt that adding the cam breathers to a catch tank just adds complication for no reason.

Nick