Hmmm. Seems I read that Nitromethane produces 4-times the cylinder-pressure as compared to burning gasoline.

How "strong" is your engine / what general condition is it in? High-Static-Compression and Nitromethane, in an engine not modified to handle it, might not be a good combination.

Have you looked into Nitromethane on the internet? Here is some information and if you scroll-down a bit, you'll see the section on Nitromethane as a motor-fuel.

http://en.wikipedia.org/wiki/Nitromethane