yes you can boost higher than that...somehow...
it detonates at 13 psi so either get a higher octane, or retard the timing, but at that point, you might as well turn the boost down a little bit.

sorry about the sarcasim.
if you are looking to gain some knowledge, 240sxforums.com is a great place to start. Read every sticky you can find on that site. Those stickies will answer most of your questions.
good luck
let us know how it goes.