Editing How to install an oil catch can (section)

===Flubba86===

Mate, I have spotted a flaw or two in your setup.
Your rear-crank case inlet is now sucking air from BEFORE the AFM! This means then when the PCV is active and open, usually in precise air-flow conditions like idle and cruising, then you are having air enter your engine which has not been metered by the AFM, which throws your mixtures way off. Also, we are not talking about just a little bit of residual air here, the PCV is quite a big air-source and actually constitutes about 50% of the air taken in during idle and cruise situations. This is why the stock setup had the air being drawn from just before the throttle body, because that air had been metered and was about to enter the engine anyway.

As with the one-way valve... are you implying that you have a valve on the rear-rocker-spout-to-airbox-line which prohibits air being blown back down the line, and only opens again when there is suction (ie. pcv conditions) on that line? If so, that is a recipe for crankcase pressure overload. Picture this... you are having a spirited drive, your throttle swings open to low-vacuum conditions, the PCV valve swings shut (because its meant to do that on low-vacuum situations) and thus your catch-can is rendered useless... now on a stock setup, a venturi-induced vacuum would be created on the rear-spout because of the air rushing through the intake pipe, and thus pull the excess air out of the crank-case that way (like a reverse pcv setup). This kinda happens on your setup, but im not sure if the velocity of the air through the lower section of the air-box would be great enough to create a reverse suction on that line, plus you mentioned you put a one-way valve on that line so you cant suck air in that direction anyway! So... your PCV is shut, your rear-spout is shut, you are fanging your engine, blow-by is being created in the crank-case, pressure builds up in the crank case, dip-stick shoots out or main seals blow out. Bad bad bad.