Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum - View Single Post - Just hooked my homemade catch can up..is it flowing right?

pr240sx · 10-09-2007, 07:21 PM

Actually, the valve cover fitting (on a KA) flows inward and outward depending on the engine load, vacumm and throttle.
At idle, the valve cover sucks fresh air and its expelled via the PCV valve.
At high throttle, the PCV vave closes and blowby is sucked via the throttle.

So, which way is the correct one? Well, depends on your application.Lets say that its on a NA KA so the real benefit of that particular separator will be done on the PCV circuit and put a small breather on the VC fitting.
If you plan to turbo, then cap the PCV rail, put a catch can and the VC line should go on the turbo intake.

At least, IMO I think that will work better that way...please, chime in your opinions!!

10-09-2007, 07:21 PM	#4
pr240sx Zilvia Addict Join Date: Jan 2002 Posts: 627 Trader Rating: (0)	Actually, the valve cover fitting (on a KA) flows inward and outward depending on the engine load, vacumm and throttle. At idle, the valve cover sucks fresh air and its expelled via the PCV valve. At high throttle, the PCV vave closes and blowby is sucked via the throttle. So, which way is the correct one? Well, depends on your application.Lets say that its on a NA KA so the real benefit of that particular separator will be done on the PCV circuit and put a small breather on the VC fitting. If you plan to turbo, then cap the PCV rail, put a catch can and the VC line should go on the turbo intake. At least, IMO I think that will work better that way...please, chime in your opinions!!