well, i may have a blown head gasket--doing a leak test tomorrow. if so, gonna get the heads flattened out (not sure of the correct term) and slap some new ones on there.
i'm interested in learning what some of the causes are as to prevent this in the future.
I've found that the main cause of blowing headgaskets is running on a dangerously lean tune.
Another cause would be overheating, which could warp your heads. That's why some people are weary about using aluminum heads. Cast iron and aluminum have different expansion rates so the head gaskets would undergo more stress.