FWIW I have NEVER seen the valley plate to be a good location. Alot of oil flying around in there at RPM and if you are pulling any real amount of vacuum its gonna make a mess in short order.
Can the valley plate area be used for the relief?
Why not?
that kind of example would be the breather/oil fill tube on chevy engines over many years. i have even seen PVC valves plumbed into oil fill tubes [with no breather] on certain POBC engines over the years.
