Oh dude, is that a shower arm coming off the pump? That set up screams "oh hell no". I like the overall idea and that's why I'm doing something similar but the way it's executed is no bueno.
The excuses in my head as to why I like the idea. A gate valve is basically a variable size valve that can be used to regulate flow although not its intended purpose in life. The control of the "flow" determines how much cold water is pushed into the block and how much exits. So bam! there's why the gate valve is there. Now the pressure relief is there just in case something, weather it be a kinked hose, blocked water passage or the fact that your pump is just that fu€king awesome and wants to force feed your engine till it starts puking water out of the intake from over pressurizing the cooling system and blowing sh!t apart.
Btw I see no regulator just a relief valve, a regulator regulates the water coming in, a relief valve releases excess pressure from a system, notice the brass t runs from the pump to the motor and this relief is on top not in the way of the incoming flow.
