W/r/t "I hold my hand over the right exhaust (rear bank) it's cold"
My first guess: it's a linkage or synch adjustment, at idle one bank is doing all the work. Raise the idle speed screw and/or mixture screw on the "cold" (rea) carburetor. Probably lower it on the hot carburetor.
W/r/t PCV
It's always at least partially open, with the restrictor (high vacuum) aperture very small and (generally) proportionate to engine size. As vacuum falls, the restrictor cone is pulled back by the internal spring and the full size is exposed. I've read 8 CFM contributed, a very small part of WOT mixture.
