Got a dumb question to ask, probably you guys would know it since it a universal item. well I'm looking into get one of those little crankcase breather filter that you put on your valve cover. i have a D16y7 engine and i checked some out on ebay, and notice they come in different sizes for the inlet. do you guys would happen to know which size to get?? or any of them will fit??

 

dont get one. your intake sucks out the pressure in the head.... too much pressure = bad. from what ive heard

 

Those breathers are stupid, joe jigga is correct, the stock intake/hose style-setup relieves pressure in the head (from blow-by??).
But ideally you'd want to run a catch can between the two lines to catch the oily-air from polluting your TB/IM/combustion-chamber and eventually causing detonation.

edit- I think some of the boost guys run them when running high though....