A thread from a couple of weeks ago has got me wondering.... The thread was about a S/C engine that had blown. One of the possible causes was that the S/C tune was made for summer conditions, and that the cooler/denser air in winter conditions had caused the engine to run too lean and blow. (Hope I am summarizing that point sufficiently well enough to understand.)

But it got me thinking....
For a daily driver in the Pacific Northwest, where the summer temperatures have a dry high of about 90*F and have a humid/wet winter low around 20*F (70*F change and much change in air humidity and therefore density from summer to winter), would a custom tune/CAI for an otherwise stock (not S/C) motor pose any potential problems with the mixture going lean due to the changes in air density? In other words, do the custom tunes take away the ability of the computer to run in a broad range of conditions as was suggested in the 'blown engine' thread??

 

No.
The IAT sensor (intake air temperature) gives its signal to the PCM, and the PCM will alter the injector pulse width accordingly.

Boost is a different animal all together in this situation.