PCV use

[Ron61]

I believe that Bob hit it right on the head. I have had both with and without them hooked up and I don't like the oil fumes on the covers plus the smell. On my 1958 Ford, the factory put a tube that plugged into the back of the intake and ran down around the bell housing and just emptied the fumes to the ground. There was always a mess at the bottom of that tube until I extended it about 1" and then the wind going under the car took it away. Since then all of my vehicles have had hoses to both valve covers, usually with a PCV valve in one cover and a twist on cap with the hose going to the air cleaner in the other cover.

Ron

[Woodz428]

In response to the comment about crankcase pressure. I do agree that it was a pollution device to burn the crankcase vapors. However, those crankcase "vapors" add up to a pressure as they accumulate.The breathers allow it to escape, but the draw of the PCV helps remove it. Modern engines wind much higher than the ones that were around when the PCV was first created, it may be that they weren't generating enough pressures to have a problem. I have seen an engine that leaked from various areas until a PCV was plumbed in, so I stand by my position. Sometimes there are side benefits that are not part of the initial application.
One of the reasons that it is applied to only one valve cover is so there can be fresh air drawn in from the other side. I would have to look at the plumbing on the Corvette you mention, but it has to have fresh air tube connected somewhere...possibly on the oil fill tube leading to the intake tract somewhere.