Dr.Jeff
True Classic
I think we are talking about two different things. And my last post wasn't clear, as I accidentally omitted the word "valve" a couple times confusing things. Sorry.and my point was that the PCV valve is an inherently bad idea. Prone to failure. The solution used on our engines is much more robust. It uses geometry and fluid dynamics rather than a valve. Sticking a mass produced nasty little valve on top of the rocker/cam cover is certainly cheaper. Basic breathers up there certainly were common but the valve was added as there are serious flow issues otherwise - well, in an engine that is worked hard. If you are doddering along behind a big 6/8 and a slushmatic, no drama, transients are not a thing...
The Fiat cyclone design has nothing to do with a 'valve', it is only a crankcase breather that also attempts to separate vapor from air. The valve in PCV systems is merely a one-way check valve, which has nothing to do with separating vapor like the cyclone design. For that matter the valve in a PCV system also has nothing to do with crankcase ventilation per see. Positive crankcase ventilation (PCV) can be designed with or without a check valve. And crankcase ventilation can be positive or neutral. So whether or not a valve exists really isn't relative to the Fiat cyclone design we are discussing.
I'm not trying to split hairs nor be contradictory, merely trying to clarify things.
