i'm guessing you mean iat (intake air temp) after the supercharger vs. before where the stock iat is?
the diff. is HUGE.
any roots-type s/c will skyrocket the iat.
i have seen iats actually cycle the sensor. that is, it gets so hot that the sensor goes from peak to a disconnect value.
on an aem, that is about 73 degrees. it's also a huge problem.
at 240 degrees plus (the limit of an aem or gm iat) density is MUCH less than at 73.
typically aem tunes do not include offsets for air temps. so that means you will get big detonation at 240+ air temps or a tune that is set for 240 peak air temps.
go to montana and run the car and it will be dangerously lean and have MUCH more sensitivity to detonation because the air is much cooler and denser than the tune.
but, tune it where you are (especially when it's hottest) and you're tune should be just fine. nearly no timing because the iat's are so high.
should you use a piggyback system, well, then runs can be very inconsistent because the stock ecu is pulling a good deal of timing due to the high iats.
want to see it in action? you need a 95+ car with an obd 2 port and a scanner. match not start iats, but end iats.
begin your dyno session with 120 iats and you'll soon be doing pulls with starting iats of 150, even if you shut off the engine between runs.
if your scanner will do it, the key will be igition timing run to run for checking consistency, forget the other stuff.
a good tuner will fill in the offsets for iat and you'll have to live with them until you find a good intercooler which will keep the charge temps much more consistent and powerful.
my $0,02
