People get this mixed up. Nitro is a monopropellent. That means that it is possible to burn with no additional air. That is not the same as an explosive which burns at a rate so fast that it causes a damaging pressure wave. It is not contact sensitive, I think there is only one occasion of it blowing up on contact when in shipment, in this case the tanker had been hauling an alkali substance that wasn't washed down, the result was that it made it contact sensitive and a small collision made it blow up.

Dragsters take advantage of its monopropellent properties and run 100% nitro (it doesn't need any other fuel to burn), as rich as possible. The only two limitations are that the richer the mixture the harder it is to ignite, thus the huge dual magnetoes; the other is hydro lock.