Quote: Originally Posted by
mebcop 
I am having an inconsistancy problem.... My gauge reads 27psi, my W/M controller is reading 25psi and my ems using the 3.5bar sensor is reading 22psi..... which one is accurate??? I find it weird also that the gauge reads 20psi of vacuum and my map sensor only reads 9??? I've heard the map sensor reads vacuum differently, but why and how?
imo, you need to forget about Gauge pressure when tuning it will just screw you up. 0 psig will fluctuate with
altitude and
barometric pressure.
Absolute pressure = ambient pressure + guage pressure
Your map sensor reads absolute pressure usually its in KiloPascals(KPa)
9Kpa =~ 20 in-Hg vaccum (NOT 20 psi)
