We've been fooling around in another thread, but I wanted to start a new one so it doesn't get lost.
You can create a custom user defined PID for logging the boost pressure above 255 kPa or approx. 22.4 psi.
After much calculation & trial and error, the LNF 3 BAP GMPP sensors can be logged for boost pressure above 22.3 psi.
You will not see manifold vacuum or pressure with this, but the lower CP pressure from the 3 bar TMAP seems pretty accurate, at least on mine.
Posted in another thread...
Logged it on the way home and did a pull, peaked at 25.4 and as it tapered down the boost at WOT, I saw 22.3 psi @ 254 kPa on the MAP. Looks pretty damn close on mine up top anyway. Still seeing .8 boost with the key on, not running. Pressure depends upon load and rpm while cruising, but that makes sense to me as the turbo spools there will be more pressure in the pipe before the throttle plate.
I'm going to look through the PID's for the 3 bar MAP voltage if it exists, then we will see mani pressure/vac. Edit: None found
To repeat... for the 3 Bar MAPs, the formula
([PID.2339]*9.369)-([PID.2340]/6.895)
(Boost sensor V * 9.369) - (BARO sensor / 6.895)
looks good but only reads positive boost pressure in the lower CP.
EDIT: I had to subtract 0.8 psi from the entire product of the above formula to get my readings to match at 22 psi, might be sensor differences.
If I'm way off base, someone please straighten me out. We couldn't have gotten this close without Gimpsters MAP Voltage tables. Thanks Andy!
Hopefully BYT will repost his 2.5 bar findings.