Given that it seems you have no idea about how nitrous oxide injection actually works, or whether it's even right for you in terms of power, I'm going to stick my neck on the line and say that you should probably step away from the car and put the spanner back in the box.
Go and read (and digest!) the entire auto section of HowStuffWorks.com (which covers superchargers very well), then read up about how nitrous works in cars (Wikipedia is a good place to start I would imagine), then read a hell of a lot more on here about how much power the internals can take, then decide whether you want more power that way, then decide what kind of system you want. After you've done all that, you'll be in a much better place and will have a car you understand and can be proud of.
Sorry if that comes across as harsh, but your post does seem to indicate you've just watched the Fast And Furious trilogy back-to-back.