just a word about water wetter. [which was the orig question] from what I remember , it was used to help prevent water from flashing into a vapor [ due to hot spots in the cyl head ] and I think it helped keep air/vapor pockets from forming on the back of combustion chambers. the term surface tension was what they used. it was very effective for that reason. it made that part of the cooling system work better which could lower temps some overall. the big gain as I understood it , was better control of combustion due to the elimination of hot spots. iirc, the gm vortec head with a closed combustion chamber had added front to rear coolant lines to the heads that were all about this same issue. they were so efficient that timing of 32* made best power. also, most racing sanctions don't allow any antifreeze, so this was helpful for lube and corrosion too ...