[fixit]

fwiw.. my updated build with higher boost @ redline caused additional crank pressure and popped out the front main seal..

simple fix, gut and cut off the top of the pvc, and put a 1/2" elbow (pvc or abs) to a 3/4" heater hose to the catch can of your choice ( beer can ?)

 

[fixit]

pre emission car's vented oil fumes (and exhaust gas that gets pass the piston rings) out of the oil breather cap to atmosphere
post emissions takes those fumes into the intake air stream to be burned.
racers typically don't like this because it can foul the plugs and cause knock