Fixed it for you!
The higher the pressure in your cooling system the higher the temp the water will boil at. This is why when your radiator cap fails your engine will overheat. The water boils out at too low a temp and the engine just keeps getting hotter. There is a limit to how much flow you can use in a cooling system. If the water flows through the radiator too fast it does not transfer as much of the heat to the air and therefore is less efficient. Some people have even put restrictors in the upper radiator hose to slow down the flow. This is usually not necessary with aluminum radiators because aluminum transfers heat much faster than copper/brass. What our engines need is more flow at the crucial low RPM's. This is why I have considered using an electric water pump.
