Finally found a video on the effects of catch can restriction on crankcase pressure. In the video he is using a DPS from the oil cap with arduino reading the DPS during idle on his Diesel engine. Basically the 50micron bronze filter we see in catch cans can increase crankcase pressure by up to 4x since its too restrictive. Better to stick with big catch cans, big fittings like cusco without any filtering.
In his setup he claims that pressure is the highest during idle since turbo boost will start generating vacuum in the crankcase (not sure if its correct but I'm not familiar with turbo Diesel setups maybe the PCV connection is before the snail). It would be great to duplicate this on our platform under boost.
But to extrapolate his finding to gasoline engines where blow by will increase with RPM/boost we'll see more then the mbar increases he's seeing. jump to 17:39 in the video for the results but to summarize
all tested during idle
Baseline no Catch can: 1.55mbar
Mann-hummel Provent (paper or steel filter): 1.54-1.58mbar
Mishimoto with bronze filter: 6.20mbar
Mishimoto with no filter: 2.8mbar
Universal oil catch can no filter: 2.1mbar
Universal oil catch can steel scour: 2.4mbar
Thoughts?