Small Block & Big Block Chevy Specific - Blow By

having problems with my truck i recently bought a complete engine from a cousin its a fresh rebuild i looked inside the cylinders with a scope it looks pretty fresh i resealed the intake to fix a oil leak. anyways everytime i take it out for a test drive i start to smell oil leaking first the grommet in the passenger side valve cover was leaking it was split so i changed it and put the pcv valve back in and it still leaks from the pcv valve so i bought a breather filter with new grommet and it still coming out from the breather i think they might have messed up putting the rings on any ideas could it be the 15w40 oil im using

i also noticed the oil pressure going down during deceleration i think it may have a high volume pump on it could this be the cause. im just trying to find any excuse to not have to pull motor back out

What kind of oil pressure are you running? I have seen crankcases blow gaskets and throw oil when they aren't ventilated due to a bad PCV valve in the past. I would change that since they are so cheap. You may want to put two oil seperating breathers on and see if you still throw oil. If you do, you are building up pressure in the crankcase and need to figure out why...