[PHPDiesel]

I thought some are using the map for tuning. Nothing else on the truck monitors boost and sends the info to the PCM. It seems to me that in order to get a proper amount of fuel the PCM needs to see the boost.

Except that the stock MAP sensor is a 0-5 volt sensor that is only capable of reading up to about 25 PSI so anything over 25 PSI isn't recognized by either the MAP sensor or PCM anyway.