Petrol and nitro are same? can we use Petrol instead or nitro in my rc car?

Petrol/Gasoline and Nitro are NOT the same. You must use the fuel that your engine was designed for.
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Petro and nitro are NOT the same - not by any stretch of the imagination.
Use the correct fuel for your RC car.
(If you use any other type of fuel, you will stand a good chance of destroying your engine due to lack of any lubrication.)
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Petrol and nitro are not the same,nitro has a much lower flash point.
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Nitro fuel is not petrol or diesel. It is most like pre-mixed 2 stroke motorbike fuel, in that it is a mix of fuel and lubricant, but there is no substitute. You must not use petrol in a nitro engine!
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true true true they are not the same
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Nitro fuel is in fact mainly made from Methanol (methyl alcohol), Oil (castor, synthetic or a mix of these), and very often a bit of nitromethane or nitropropane. There is no petrol whatsoever in it. Premix motorbike fuel will not work, nor will any fuel containing petrol. Use the correct stuff, I know its dear but the cheapest way of buying it is by the gallon from Model Aircraft shop. Also dont use the high levels of nitromethane unless you have to - many engines quite happy on 5%.
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Model aircraft builder and flyer 30 years