I've seen that Hummel unit. Looks nice. But again, it also has the diaphragm. The question is: will it freeze when you have a really cold day? And I know we have some nasty cold days here in the winter. If this happens, it's the equivalent of the OEM CCV, which when all is ideal works as intended.
The issue in the cold climate is the water vapour that is sucked together with the oil vapour. The mayo obtained will freeze. If it collects in the same place where the actual OEM CCV sits. The e9x have the diaphragm inside the air distribution piece somewhere. Not sure where the draining funnel is located.
If we can place only the diaphragm in a place where it will never freeze, no matter how cold it's outside, and on the same token to resist heat, and have the collecting/draining unit somewhere, where even if it starts freezing at the beginning of the journey, but will warm up and melt the mayo eventually and let it drain in the oil pan, that would be OK too.
That filter in the Hummel design is overkill if you drain the oil.
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TMS underdrive pullies - Stewart WP - PSS9 - Beisan Vanos seals - Zimmerman cross-drilled & Akebono Euro - Deka 649 MF - 55w HID headlights - 35w HID foglights - Hualigan double din - ACS (rep) alu pedals - Euro central storage console - Breyton Magic Racing staggered wheels - M5 bumper - M5 steering wheel - Tint
Stable: e39 M54, e53 N62 & Tribby