Anyone ever see a crack in a magnum head like this before? I removed the exhaust manifold to replace the gasket and 2 broken bolts. I found this while spraying out the threads.
If it were a crack, there should be coolant leaking into it because the other side of the port is the water jacket... If it were cracked all the way through, there would be an antifreeze leaking into the port because it has more pressure than the exhaust port... The higher pressure would win...