The only problem I see in trying to draw links between CPU water cooling and car engine water cooling, is the desired result of each, both use overkill style setups, but a car's watercooling is designed to keep the engine
within a specific temprature range controlled by a thermostat, where as a cpu's water cooling is designed to keep the temp as
close to ambient as possible.
I propose an easy solution to this whole debate, throw away your rads and use evaporative cooling instead