2015-2020 STI (North American)
2015-2019 (ADM Spec).
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Example: If you live in Denver at 5280 ft and are trying to run a peak boost pressure of 15 psi, your turbocharger has to work the equivalent of making ~17.5 psi at sea level.
There are barometric compensations within the factory ECU that lower boost targets as you climb in altitude in an effort to keep the turbocharger in its optimal range. The COBB performance maps utilize these compensations and therefore, it is perfectly normal for the final boost target to be lower than what is listed for your map.
Boost Select:
All maps designated with "Boost Select" in the map name have a driver-controlled boost target controlled through the SI-Drive system available on the 2008+ STI. From the factory, SI-Drive will modify throttle settings and change the relation between what is done with the accelerator pedal and how the throttle blade reacts; [S#] being the most aggressive throttle settings, [S] being less aggressive, and [I] being very conservative. What we have done is take that functionality a step further. The "Boost Select" maps have selectable boost targets enabled by toggling between [S#], [S], and [I]. [S#] will target the highest boost level, [S] will be a medium boost level, and [I] will be the lowest boost level (wastegate spring pressure). You can find the specific boost targets for [S#], [S], and [I] in the Map Version Notes above.
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