I wasn't speaking of nitromethane at all. In fact if you want to talk about N0S:
When N2O breaks down in the engine's combustion phase, there is an additional benefit to performance: the oxygen atoms in N2O, as they are freed from their bond to the nitrogen atoms release heat in an exothermic reaction, i.e. one producing more heat than was required to initiate the breakdown; contributing to the overall power increase. The additional amount of heat produced, like that achieved above by increasing the charge of fuel allowed, by use of "nitro," similarly increases engine efficiency and performance, which is directly related to the difference in temperature between the unburned fuel mixture and the hot combustion gasses produced in the cylinders.