318 - High Oil Pressure

I used comp cams break-in oil for the initial start up
Good. How long did you run it before changing to the synthetic?

And as for the 'acceptable' level of blowby with the PCV pulled out of the valve cover, a good amount would be for some vapors to just slowly drift out of the valve cover at idle. Again, it is hard to quantify, for me at least....you do enough engines and you get used to what is normal.