Water Cooling is a good idea on gasoline engines however from everything that I have learn talking to the turbo shops say it is a good idea to avoid water cooling whenever possible due to the fact the running your coolant through a turbo exposes it to extreme temperatures which "burn" your antifreeze causing the heat transfer properties of your coolant to be decreased. As long as you let your turbo cool down for a minute before you shut down you should be okay. Just my .02