If you are using professional software (HP Tuners, EFILive, Alientech), their internal repositories have "Hot" variants. Specifically, for a 5.9L Cummins (1998-2002 VP44 or 2003-2007 Common Rail), a "120 Hot" file often increases boost from 28 PSI to 42 PSI.

"Bricked my PCM. Don't trust free downloads. Buy from a pro." —