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      07-25-2009, 10:17 AM   #36
hotrod182
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Quote:
Originally Posted by scalbert View Post
Shouldn't that be a wink as that is so far from the truth.

H2O injection is primarily beneficial due to the heat absorption from the quick evaporation of the water. High RH is already a vapor and does not provide a cooling effect. If anything, it increases heat retention.
That is correct, heat of evaporation is what brings benefits with H20. What you are saying is true if air is saturated with high RH at 95F ambient, and discussed engine operating temps remain at those temps. But what happens to that saturation level when temps are raised considerably? (such as in your intake tract at temps approaching 170F after the intercooler!). The air at those temps is no longer saturated with water vapor, and there would be benefit from the evaporation effect. Warmer temps will support more evaporation.
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