allright,
compressed air= hot air, well warmer than normal, that also depends on what turbo and the efficiency range you are in on that particular turbo. i wouldn't worry about that on this setup.
intercooler on 5-6psi ins't necessary, but we all know boost=crack. so he will want to turn it up, thats where its good to have an intercooler, because as covered before, more pressure=hotter air.
5-6psi will just give him a taste of what it can do.
Your kidding right??
Well since you appear to want to be an e-smartass. The intercooler, like I said, cools the intake charge which will help improve the combustion efficiency(ambient air). The FMIC simply raises the det. threshhold so you can throw more boost at the motor....that's it. Running a car with no intercooler does not let air into the throttle body at exhaust temps...that is silly....but since you have "first hand experience" I guess you already know that.
Intake temps and engine temps are different. What your saying almost sounds as though you are implying that a non intercooled cars IAT would be the same as its ET.
radiator...
he may be an e-smartass, but you are an e-dumbass.
IAT has nothing to do with combustion efficiency, hot air can burn fully burn fuel, so can cold air, you can get a 14.7AFR in both(which is perfect burn). has nothing to do with det. threshhold, as long as you are within a rich to stoich AFR. now hot air can cause det. but you would'nt contoll it by cooling the air. you would retard the timing. which is what factory turbo cars do with a know sensor.
so i would recomend to get an IC, even a used dsm sidemount is better than nothing, but you can run it without, as long as you take proper precautions.( timing)