When it gets time to tune the Magnum motor with boost, search Duner on
www.theturboforums.com
He has a pretty good fuel side recipe, that keeps fuel "right" and inline with the increased air flow.
keep in mind, stock stuff is speed density, it does not see improvements in air flow via mass air flow sensor like other OEM systems. Comparatively, it's dumb. If I recall, Duner used a inline booster pump in addition to stock intake pump (working on a Dakota), and ran an FMU with a certain plate, so the fuel rose appropriately to the air flow increase, that the OEM computer cannot see.