A basic breather will relieve crankcase pressure, but not much else.TORKER wrote:has anyone run it with a breather on the other vavle cover just to keep engine clean?
Pre PCV motors used a draft tube that created a small vacuum at speed, but did nothing when the car was stationary. It wasn't EPA-friendly, but did keep large amounts of water from accumulating in the crankcase, providing the oil was heated up.
Putting a breather on a modern EFI engine with MAF sensor creates a vacuum leak and unmetered air enters the intake unless all PCV vacuum and make-up air ports are closed up.