As I've said before there are pilots and there are operators. If you abuse the engine it will not last. The myth and that's all it is that lop is a magic fix for all is just that. If it wasn't no engine would make o/h at all with execption to a lop engine and this is clearly not the facts. Cly press is not the cause of a head failure at all. As I said before. Learn se basic engine knowlege on any hangar floor. Yes but a lot of meat bombs don't do a power decent. By adding power you are not getting shock cooling across your engine. And factory o/ h engines have what. New cly as standard.