Intake air temperature
 

With some help from Scott.t I have decided to keep standard Ecu in for now,

However in the future when I have recovered from the current fuel induced bankruptcy, I may wish to modify the 99my a little and get it custom tuned.

I am suprised to find that it does not have an intake air temperature sensor after the intercooler, which I would have thought is essential on any turbocharged engine, standard or modified, although the JDM version does have one.

so the question is would it be wise to fit an air temp sensor with apropriate wiring and source a JDM ecu from this model year, then have this set up custom tuned to suit.

JDM intake temp is exactly that. It's on the intake between the air filter and MAF. So pretty useless.
It needs to be between the intercooler and throttle.
Some people have done this and I thought about wiring in to my apexi using a blanking plate on the DV mounting and an air temperature sensor threaded into it. But it's something I never got round too.

hum, I agree, I cant see much point measuring the air temp up near the maf. Every turbo car Ive had before has a sensor after the intercooler.
Presumable the temperature correction maps could be altered to suit post intercooler readings.

I would think this would be particularly important on a modified car, when retaining the relatively small top mount intercooler