^^Yeah I've seen a lot of the same on iwsti.com. It's hard for people to take criticism - even if just asking tough questions - and also be objective about something when they've just spent $300+
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Forgive me if I'm wrong but I don't believe the grimmspeed unit relies on cooling for separation. It simply wouldn't work because the unit is connected to the oil filler cap/valve covers which get really hot.
Regarding #1, I had similar concerns as you but this answered many of my questions: (mainly posts 735 and 739:
http://www.iwsti.com/forums/2-5-lite...thread-74.html. He explains that grimmspeed uses an impactor for separation. (I'm no saying this guy is 100% correct but grimmspeed is also posting in that thread too fwiw.)
Regarding #2, I have to agree with you here. It seems like it would just push more crankcase vapor from the oil fill through the a/o separator outlet to the turbo inlet. However, many people have posted picks of clear tubing with the grimmspeed unit and it clearly shows oil going in and not going out, so it must be effectively separating the oil from the air (that's all you're really looking for).
The only thing I'm still unsure of with the grimmspeed is how it works in racing conditions (it sounds like most of the testers were just on dd'ers), and how effective it is at separating the oil if you delete the pcv valve and basically route it like crawford does.