dude... dont take this the wrong way, but go get a book and read a bit.. there is alot more to nitrous than the differences in a wet kit vs a dry.. I have had nitrous in several cars, and its not something i would suggest for a bike. the simple fact that when the "shot" of nitrous get to the engine, the power (depending on what your set up for) could be a little overwelming and you could esentally just flip the bike over. that would probably be the best case... go read up on how nitrous works, how it generates power.. and the much debated differences between a wet kit vs a dry.. once you know how it all works, then you will be able to figure out how best to utilize it for the fz6 if its something your serious about doing...
for the money.. it will be expensive, but i would go with a wet kit with (most important) a fuel preassure safety switch and a full throttle switch.. i probably on the fz6 (someone have a stock dyno chart??) never use it below 6K-7K due to the sudden rush and the liability of it creating too much pressure for the engine to handle.. i only think you could really do 15hp more before you have to do some engine buildup.. and this would probbaly cost you in the relm of $1000 at least and you would need some dyno tuning time for it to work all in sync.. its a little more complicated than the fast and furious make it out to be.. you dont just go "hey lets put this on" and expect it to work the way your intending it to.. hope it help.. good luck ..:thumbup: