Here's some more help...
Since your getting a 96 240sx, it will have 155hp at crank, which is usually about 130hp to the wheels... since you didn't feel like doing research on mods and gains, I'll summarize it for you:
Injen Cold Air Intake - ~5hp peak to the wheels.ASP pulley or Unorthodox pulley - ~5hp peak to wheels.Hotshot headers - ~10hp peak to wheels.Exhaust - ~5hp peak to wheels.Cams - ~10hp peak to wheels if combined with all mods above.
There you have it, with all those mods and a tuned engine, you will net about 160-170hp to the wheels. If you want more horses, you will have to add nitrous, swap out the pistons to get higher compression, or do major head work. In other words, any gains above 160-170hp and your looking at major $$$$$.
