Nitrous doens't really help all that much considering we are already running nitro methane in these engines. Also, one of the main advantages of Nitrous is that it cools the intake charge before it enters the engine, however the intake tract in a 2stroke RC nitro engine is so short that the intake charge does not get a chance to heat up very much before it enters the combustion chamber.

Also, because these are 2 stroke engines most of the increased combustion pressure and tempuratures due to the nitrous is lost out the exhaust. This is the same reason that forced induction is ineffective on 2 stroke motors.

If we were running a 4stroke engine then nitrous and forced induction would be much more effective.