How do you set up the scanner to tune with a 2-bar or 3-bar MAP sensor on a custom OS?

Here is what the documentation says. Each point links to its source; tables and names vary by computer, operating system and tuning software.

• P01, P59; LM7, LQ4, LQ9, LS1, LS2; 1999-2007: HP Tuners' 2-bar/3-bar MAP support (the 2.5-bar custom OS) adds a Boost VE table spanning 105 kPa to 255 kPa with better than 5 kPa resolution in the boost region, retains stock VE resolution in non-boost areas, adds a MAP-referenced Boost Enrich table in 5 kPa steps, and runs in speed-density mode only. (HP Tuners)
• Sources differ: Conflicts with simpler '2-bar good to 14.7 psi' statements; the OS boost tables actually read to 255 kPa when paired with a 3-bar sensor.
• E38, E67, E92; LS Gen IV; 2005-2013: E38, E67, and E92 ECMs can interpret 2- or 3-bar MAP sensor readings, but the MAP calibration data still has to be changed if the ECU was not originally calibrated for a supercharged engine. (LSX Magazine)
• LS1B; LS Gen III; 1999-2006: Stock 1999-2006 LS1B ECMs cannot measure more than 1 bar of manifold pressure (about 14.5 psi or 105 kPa); boosted combinations need a 2- or 3-bar MAP sensor with corrected sensor scaling. (LSX Magazine)
• E38, E67; LS2, LS3, LS7; 2006-2015: For boosted Gen IV swaps the controller must be set up for a 2- or 3-bar MAP sensor, since the factory calibration only models naturally-aspirated manifold pressure. (LSX Magazine)

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