damm.......no reply's? this is sad.......LOL, well dude why dont you start witht he basics? I/H/E....i have a friend that is putting about 265WHP on an N/A 98 Maxima.....ofcourse hes got all the internal work you could do. Search around a couple of forums like.....Nicoclub.com or nissanforums.com they are very good and information flows well there.
Good luck