Has anyone had an issue with Eddie Marine exhaust creating to much block pressure and causing a head gasket problem?

Its the water presure high ??? Maybe it a casting flaw in the water ports in them?maybe the head gasket was allready going?

If it is restricting the water that much I would think it would be over 40psi

Should be no more than 10-13 lbs. You may be getting a little vapor block.

It's common to change the exhaust out and have pressure problems. It's one of the things that should be checked as part of the installation. This problem would not be limited to just Eddie Marine. The engine will hold 25psi just fine. You are proably in the 40psi range.