does any body know how to make NITRO GAS for a remote control car?

You will need Nitromethane, Methanol and Castor or Synthetic oil. In addition to these 3 primary components to rc nitro fuel, there are often other additives added in small quantities which help alter some of the characteristics of the nitro fuel. Among others, these additional rc nitro fuel additives might include anti-foaming agents and substances to help prevent corrosion inside the engine.

But giving the current price of nitromethane, well over $50 a gallon) plus the cost of the oil, methanol and other additives. It would be cheaper to buy it already blended. You might be able to ask around at the race track or hobby shop and see if anybody will/can make you a custom blend, if that is what you are looking for
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R/C Racer/Basher since the early 90's

You need to get the exact mixtures and you need to use the purest ingredients you can find. Any impurities will ruin your engine.
Castor and synthetic oil are relatively easy to find, but nitromethane and methanol are pretty specialist stuff not to mention quite dangerous so I doubt just anyone can buy them in large quantities.
It would be easier just to buy normal ready made nitro fuel.
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