Hello Poolman,
This engine is high compression, this results after years of use a bit of oil useage. The hose from above oil pan to breather should be free and clear with little or no build-up of oil residue. Take your oil cap off and put your hand over the hole. Do you feel a small suction at Idle? Bring RPM'S to 2500, do you still feel a small suction? This next step is a bit harder to do, chock front wheels, engage E-brake, put car in drive and bring the RPM to 2500, do you feel blowy now. If it is a small amount I wouldn't worry about it, synthetic oil may reduce the build-up on the rings, but may cause more seal problems. Also the way the head is designed there tends to be quite a bit of oil around the valve seals, so if the car is around the town car it can consume up to 2 quarts per oil change. If its more than that, you might want to get the valve seals done. 1 b---- of a job, but could reduce your oil useage. Pauli