deltaMAP = pressure difference across injector = absolute rail pressure - MAP

note: absolute rail pressure = 500kPa absolute = 400kPa gauge (58psi gauge)

e.g.
deltaMAP=400kPa --> at WOT with NA
deltaMAP=440kPa --> cruise with OEM cam (40kPa vacuum)
deltaMAP=460kPa --> idle with OEM cam (60kPa vacuum)
deltaMAP=500kPa --> theoretical full vacuum (100kPa vacuum)

deltaMAP<400kPa --> boost (MAP > 100kPa)