Will really really bad valve seals cause engine exhaust to escape into the valvetrain and pour smoke that smells like exhaust out of the oil fill on the valve cover?

 

its possible, but it usually leaks oilon top ofyour exhaust valve

 

It's really possible and it's not cheap to change... unless you do it yourself but you will need a new valve, maybe a new seat valve and the valve guide, you will need the tool to remove valve but you can make one if you have a welding machine and you will need the head gasket kit. If you do it yourself i think it will cost about 200$+ with new head bolt

 

I'm not pulling the head .... yet

I will fill the combustion chamber with compressed air via anaircompressorand change the valve seals if the seals are the problem. For now I'm debating weather to take the free route but hard labor and just swap my 95 motor in so I can rule out the BS. this smoking out of the valve cover really sucks and its causing the motor to be lagy on the high end and low end and sometimes it will show a sign of power like its former self used to have.

I changed the pcv valve and still didn't fix the problem and I can't get a compression gauge any where that will fit in the spark plugtubes and the only one i did find was a 40 year old one my dad had which wasdesigned for426 hemi engines andas of nowi don't believe itto be acurate for a few reasons age and its a push against type.