I have just switched from the GM 3bar map to the AEM 5bar map sensor. Now, I've successfully tuned cars with and used both sensors, so I'm not questioning the sensors themselves. The question I have is: have any of you switched between these 3 sensors and seen any sort of discrepancy between them? What I mean:

Looking back at my logs, I'm seeing 3-4psi less of boost with the idential setup using the AEM sensor than I did with the gm 3bar sensor. In this case, I was seeing ~20psi of boost with the GM sensor, and with no changes to the setup except the map sensor I'm seeing 16-17 psi of boost with the 5bar. This is with no other changes to the car at all.

This leads me to 2 possible situations:
1) The AEM 5bar sensor is translating an identical pressure to a lesser value than the 3bar sensor (i.e., 20psi to a GM 3bar = 16 psi to a AEM 5bar).
2) My setup is making less boost since I've changed the map sensor... and since there have been zero changes to the car, I would start to suspect an issue with something mechanical like the turbo itself.

Thoughts? Can anyone confirm/deny that an identical pressure applied to these 2 sensors will cause the same or different translated pressure readings?

 

i dunno my GM 3 bar reads the same same amt on of boost as my greddy boost gauge vs AEM display

 

I know that with the S200, the cells are off a little bit between the two (3 bar/5 bar). Even in the new S300 you have to set the calibration for it (voltage). That may be the only thing that I can think of for you in your case. Take it by your sig that this is an AEM EMS?

Jason

 

Check the AEM website. http://www.aempower.com and look search the forum. They claim that the AEM sensor is much more reliable than the gm sensors since the aem sensor is a medical grade sensor with much stricter tolerances. Just what I have read from the AEM ems gurus.