PCV question: why does pcv sometimes not connect to airbox?

[cody.holdridge]

Long story short, I replaced the engine in my girlfriends overheated '02 Outback. I replaced the ej25 with an ej22 from an '01 Impreza.

I swapped manifolds, cam/crank gears and sensors.

 

Right now it runs and drives fine(threw codes but havent checked it yet) but I have two different incompatable pcv systems, and I want this figured out.

 

The '02 2.5 had the pcv in the engine block.

 

The '01 engine has the valve in the manufold which I can swap, but have no attachment at my airbox. Can I block this extra hose? Why did it originally attach to the airbox on one, and not the other. Both my 99 2.2 and 99 2.5 have nipples on the airbox for it, but not the '02 with the reverse directio valve.