The only problem with sqirting water on any type of radiator is that it 
short circuits the cooling process and actualy makes an engine retain 
heat.  If you keep the radiator nice and cool the engine gets really hot!
it's a short excersize in physics but if you think about it it makes a 
lot of sense.  Hence squirting water on an oil cooler will kill your 
engine twice as fast, on the heads doubly so!.  The reason your engine 
stays cooler when it's rainy is that the humidity is very high and water 
vapor carries heat away from the fins faster than air.  If you can find a 
way to prevent evaporation from occuring on the fins when squirting the 
water it may actualy help but I doubt it can be done easily.

Scott

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Any nation that trades Liberty for Security deserves neither.
---Ben Franklin
'69 transporter 
conrad@centcon.com  sbeckst@dpc.com becksteads@aol.com