I’m 99.44% sure that I’m not having a psychedelic flashback, so not imagining the results of using water wetter:
1st, no one is going to use it unless they are are already having overheating issues.
It will drop the temperature by 5-10 F when the user is using 100% water. That was my experience. Often just a slight drop in temperature is enough to give the engine needed relief.
But for people using an antifreeze mix, the temperature reduction is less. And to the credit of water wetter’s manufacturer, RedLine, they point this out. But even “less” is better than “zero”
There are many racing organizations that forbid the use of antifreeze. For those cars, often running on the edge of overheating, water wetter is a valuable tool.
But for most street applications, the stock cooling system is adequate and in no danger of overheating with normal use
Z