Dlotz D use should have a PCV valve on the motor. Some people like them at the back of there manifold where the breather is from the old days. I run mine in the r/s valve cover and have a vent in the L/S I also run high pressures and "G" turns. No smoke or
oil being sucked up into the valve. I flood the heads for
oil as well. My valve covers are the tall ones. The valve stem seals should be total seals. If you take off a cover and look betwwen the valve springs you should see a small wire going around the top of the seal. If not you may be running just unbrella seals that may cause you this problem. Is the
oil on the spark plug threads inside or out side where it is placed? Are the plugs black and wet? Blue smoke is the sure way to know you have an oil burner or problem motor. You should have a port in the manifold or base of the carb. Get a piece of 3/8" rubber hose and run it from a port or carb to the valve cover. You might need to get a groment kit to put this on. Replaced the plugs and go for a good road test. Check motor after it has cooled off. This should relieve any pressure inthe motor for normal driving. Rick L.