intercooler question

i hear that if i want to run low boost i can avoid using an intercooler, hows that possible, how can i do that?

Yes you can as there is less chance to detonation at lower boost (lower heat). You do this by running a tube from compressor outlet to the throtle body.
Judging from your question you do not know much about turbos and how to set it up. I would recomend you research a lot more before going turbo.

My friend has a Z31 turbo at 12psi with no intercooler

http://nissaninfiniticlub.net/photopost/showphoto.php?photo=11464&sort=1&cat=500&page=5
As you can see here there is no intercooler. (nissanfantics car when was first inroduced to boost)

Im pretty sure to be on the safe side you need to stay around 6 PSI...thats what Ive understood of boost.

Moved to Forced induction.

many turbocharged cars ran with no intercoolers for years... many many years. intercoolers did not become prominent untill the mid/late '80s. most turbo cars never came with intercoolers untill then.

the first i can think of were the dodge shelby turbo 2 daytonas, shadows and Omni GLHS's. or maybe turbo 2 rx7's.

As long as enough timing is pulled, you dont really need an intercooler. Youll sacrifice hp though. My friend has a turbo svt contour running a T-28 at 12-13 psi with no intercooler. He does have water injection, but doesnt use it all the time.

the first i can think of were the dodge shelby turbo 2 daytonas, shadows and Omni GLHS's. or maybe turbo 2 rx7's.

Though I'd love to say that Chrysler was the first I think that SAAB was probably the first to start using intercoolers.

Anyhow, the purpose of an intercooler is to cool the coming out of the compressor side of the turbo before entering the engine. This gives you a little more power but more importantly I cuts down on the risk of detonation. As long as you don't go over six PSI you should be fine with stock timing. You can run more boost by retarding the timing or lowering the compression but you're going to lose horsepower and engine response. You'd just be better off running an intercooler in my opinion.

You can also run higher octane fuel....

For a street car, I think everyone can agree that you should just invest in a decent Front Mount intercooler. Esp with the aftermarket of our beloved 240sx, there is no reason not to.