I was doing some research on engine coolant and came across the some information that compares the specific heat, boiling point, heat of vaporization, surface tension, and vapor pressure of water and non-aqueous propylene glycol (NPA). A 100% mixture of NPA is superior to water at removing heat when used as engine coolant. It seems to me that when you look at this table, that NPA would be superior to water at removing heat in a combustion chamber as well. Here is the link:
http://www.evanscooling.com/html/tech1.htm
Has anyone ever investigated this? It seems like the same properties that make it a better coolant would make it a better injection liquid. Can anybody elaborate? Is there any reason not to run it other than cost?