canardlover,

This is in response to your original question: " Is there a good easily available nitromethane substitute to improve idle and transition of certain engines..?".

I have used ether (diethyl ether- the same one used in diesel fuel) in percentages of 5%. This was in a Kyosho .21 car engine for which I think they recommend 20% nitro. It seemed to run slightly hotter but the idle & transition was excellent. Much, much better than 0% nitro fuel in fact, but I cannot tell you how it compares with nitro fuel cause nitro is very expensive here ($20 for 500 ml).

It runs the same as 0% nitro and exhibits no sign of rough running or detonation. The oil used was 20% pure castor.

After running the head was removed to see if there was any visible damage to the piston crown or head. None whatsoever.

I dont think its advisable to go above 5% ether.