My original head was done over at a machine shop. It turned out later down the road I discovered it was using antifreeze. One of my valves eventually stuck open a little. There was a crack near the exhaust valve that was allowing antifreeze in to the combustion chamber. Some of it got in a valve guide and made it sticky. My guides were also worn really badly.
If you look at the top of your head, the exhaust valves are on more of an angle then the intakes. Also you can see how they are positioned to feed the intake and exhaust manifolds.
