I have spoken to a friend of mine who has tested many different coolant variations (water/coolant/glycerol/water wetter/ect...). He has done this both on the track and on engine dynos. He stated that water by itself conducts heat away from the engine better than any other coolant he tested. However anti-freeze or water wetter give the water pump a necessary lubricant (and as an added bonus anti-oxidant). If you can maintain pressure in a system water can be effective well above 240.
The point here is: I wouldn't use Evans because I doubt it has ability to transfer heat away from your engine as well a 20/80 coolant solution. And BlackIce is one the money when he says the ECU will start to deal with the heat in a way you won’t like. You could reprogram the ECU but if you are gona go for broke you might as well rip off the AC and put on a real radiator and thereby solve the cooling problem once and for all.
The point here is: I wouldn't use Evans because I doubt it has ability to transfer heat away from your engine as well a 20/80 coolant solution. And BlackIce is one the money when he says the ECU will start to deal with the heat in a way you won’t like. You could reprogram the ECU but if you are gona go for broke you might as well rip off the AC and put on a real radiator and thereby solve the cooling problem once and for all.