Originally Posted by Carl Froehlich
I did a careful calculations of actual MP on the ground with the engine off (correcting for field elevation and local barometric pressure). I ended up inserting a correction factor of -0.4” into the SkyView EMS to get a more accurate MP readout (as in before the correction the MP pressure was reading 0.4” higher than actual).
Assume the whatever you are reading for MP is off unless you calibrate the sensor.
Yup - If I had a Dynon system (D180, Skyview EMS, etc.) I could easily adjust MAP readings. Unfortunately, the Garmin G3X suite doesn't have a simple means (read: none that I can find) available to do this...
However, doing the same math on the ground yields a number what's within .01" of what the Garmin G3X reports...so, no adjustment needed.