If you are referring to the MPXH6400A, then the offset officially is (yet again) 20.

Jim

I like how reverant just watches and watches, then when something very technical or electrosavvy comes up he comes in and saves the day.

I saw that. However, the readings I got on my palm were too high compared to readings in megatune when I used 20 as the offset.
I saw the same offset of 20 listed for the 2.5bar. kpafactor.ini disagress and says 11.

Solution found:
https://www.miataturbo.net/megasquirt-18/whos-got-mapdaddy-13504/

Figure, I'll lock this one and any further discussion can be at the other thread.