RAMM
68 posts and not one help from you,And then 4 in a row;and still notta one helps the OP.
So here's a recap;
It has "a slight low end miss" It's either misfiring as in down a cylinder or its not-nothing slight about it.
It has enough air pressure in the rad to blow the cap out of his hand and send it airborne.I'm sure the image of "Old Faithful" is a very inaccurate one. Probably just a normal release of normal cooling system pressure.
it's pushing a black fluid out the stathouse, but doesn't seem to have oil in the rad. That's because its not oil and probably black rubber **** off the inside of the hose--I see this often hooking engines up to the dyno
cylinders are still"oily looking"Cylinders looking oily is awfully vague and could be as simple as getting the carb/timing right and actually breaking it in properly.