Originally Posted by JimBlake
It depends on how much blowby you get past your piston rings. So it's not an exact point, but it's at higher rpm & more-open throttle. Whenever the amount of blowby exceeds the amount sucked out thru the PCV, then the flow reverses in that vent line.
You could put another catch-can in that vent line. If you use a check-valve you risk pressurizing your crankcase - not good.
What do you think of the "Y" idea with reversed check valves at the "Y". The "Y" fits right onto the valve cover hose barb? The "good" air line is open one way inward draw; the back pressure is handled by the reversed check valve into a catch-can??
You know where I saw a "Y" vacumn tube? On the back side of the intake manifold for a B18c1. There is a "Y" connection splitter.
I know you will say "put the dirty air hose up your nose!" haha. I am going to try this. Little check valves are inexpensive, or maybe I should go to the junkyard and cut out some booster cable check valves - they are one way, right? Thanks.
OK, I'll just go out and inhale the bad air now.........