Pulled the valve cover today anyone ever see this stuff?

Ahhha, the humidity of PA I know it well....
Just got to say that it is common with those cold blooded Slants.(my favorite engine.) As stated above PCV has allot to do with it. When I was racing my Slant drag Dart I removed the PCV and installed Vac-u-Pan system and that's what the inside of my cover looked like.Went back to the PCV system and all went away. Just a thought. I also used to run a 160* thermostat in my 170 Valiant.Changed it to a 195* and the car did much better as a daily driver. Most of my driving was 3 to 5 miles one way.