retorque heads to solve issue?

Or dust from the road. Engines get an oil film on them, from them being an engine and when you combine dust and oil, they look dirty. I tried to find a very minor oil leak in a blown big block Chevy, using florescent dye. When I hit it with a black light after running for a few minutes, the whole outside of the engine glowed.
Did you use any sealer on your gaskets or put them on dry? What head bolts used or studs?
I retorked my trick flow heads, no I didn't back them off. Yeah, probably a pinch above torque specs, but so are most everyone's torque wrenches out of spec.