I noticed an oil pressure drop, and decided to check my oil. The dipstick measured perfect, and the oil is as clean as a whistle, however, when you take the top fill cap off of the valve cover it is a different story. Also, I notice it is blowing oil onto my intake manifold. At first I thought a head gasket, but the oil in the pan is clean. I have never seen this happen before. Anybody know what would cause this? It is a 1967 390. Take a look at the picture below. It is like this in both breathers.