I installed a GM 3 bar map sensor as per the wiring dio on this forum. I then tried to reset the pim settings on option 2 to 41800 and 0 offset, but the data logit then changed my settings to 9830 and 0. I probably need to change something else, but what?

 

You are using the new software, 41800 is the wrong number. Try 6630 offset 0

 

Calibrated GM 3 bar setting; 43500/0 for FD3S or 6525/0 for Universal.
This will make the pressure readins on the Commander and Datalogit be correct.

 

What I have found is that altitude plays a roll in this, 6525/0 is not good at 800ft, the 41800/0 is meant to be at sea level, 43500/0 is way off. However 41800/0 reads -50 on the commander when the car is not running at 1000 ft above sea level.

 

The calibrated values are at sea level and will make the PFC and DL boost values match your boost gauge.

Relative pressure gauges are calibrated to read 0 psi at 1 ATM at sea level which is absolute pressure of 14.7 rounded.

You should not calibrate for 0 psi at different altitudes.

 

That is correct, you do not adjust for altitude. I have tested the 41800/0 at sea level it is correct. I did some checking this morning and 6270/0 is the direct swap for 41800/0 in the new software.

 

It looks like GM's 3 bars are not that consistant as I did the one for a friend who used your wiring harness.

It was done here in SW Houston which is about 85' above sea level. The gauge used to calibrate the map sesnor is a 0 - 30 psi 6" gauge with a full scale accuracy of .05%. That is 1/2 of a percent error rate. That means at 30 psi, it would be within .15 psi. A 0-30 psi regulator was used between the air pump's 0 -300 psi regulator (set at 40) and the gauge setup.
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Either way it only makes a difference if you want the PFC Commander and DL to accurately show boost. You can still properly tune no matter what is displade.

 

GM? with poor build quality on their electrical components???? I would've never guessed!

 

So on a FC I would use the universal MAP numbers since I will be running higher boost then the FD calibration numbers?

 

There very well could be some variances in the GM sensors, I have noticed even with the FD oem sensors that the commander readouts vary +/- 10 (car not running). We will be getting another shipment of GM sensors in next week sometime, I will see if there are any variations within that lot versus the ones that we currently have.

Fc3s Murray- The terms universal and FD calibrations are referring to the FCedit software being used for the DL.

 

- my error, should be .5%.

 

6630 and 0 worked for me I am about 10 ft above sea leve. it reads +.02 - +.04 depending on temp and humidity. you gotta love nj thanks for the good i nfo