the filter just keeps oil from slashing out, it helps keep the liquidy part of the vapor in the catch can. it there was just an open hole you get oil spray everywhere over a long period of time.
a catch can is a name of a baffled can, not a system. the endyn setup incorporates this type of can into its catch can setup along with fittings for the back of the block(where crank case pressure vents thru), lines, fittings, and a filter for the catch can
keep in mind a filter doesnt always have to be sucking in like an air intake filter, there type of filters work in the opposite direction...from the inside out
Last edited by 99B16Si; 03-23-2006 at 04:53 PM.