......what EXACTLY makes it work? I picked up a bottle the other day and plan on adding it to my coolant, right from the start with my new engine.

I use this stuff in my Suburban and have seen coolant temps drop an average of 10 degrees when towing my boat.
But WHY?

 

IIRC, it affects (reduces) the surface tension of the coolant and water, which allows better heat transfer.

 

Correct. It works on the same principle as soap, in a very basic sense.

 

I am also knowledgless on this. Why not just use Evans? it isn't good enough?

 

What does Water Wetter have to do with Evans coolant? Nothing.

Evans is a completely different coolant and does NOT use water (in fact, you have to purge all water from the system for it to work). There are pros and cons to using Evans....many good threads on it.