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Hi,
I noticed that the ZR1 map sensor is listed as a 2.5 bar sensor, but if you look at the scaling in a stock ZR1 tune file, it is scaled at 312.500.
I have used it in other applications, and found that my KPA is off (100KPA might read 135 +-) which would coincide with the sensor being a 2.5 bar, yet why is it scaled by GM at 312.500 when an older style 3 bar sensor would be scaled at 282?
Anyone come across this?
Thanks for your time. :cheers:
Good question but 312.5 works! Thats all that matters! Maybe its not a 2.5 bar based upon the math!
There is more to the MAP scaling than meets the eye. The number defines the slope of the MAP response line at a certain voltage somewhere towards 5V that no doubt varies but is not exposed so it depends on other factors like this inc sensor specs and the offset as well.
I am sure it depends also on the offset. The slope may be high, but if the offset is different it will account to what it should be.
Correct. The same is for the LSJ cobalt motors. The offset + the scaling value combined together provide the proper MAP reading. This is why I am not a fan of just making changes until KOEO MAP reads 100. These numbers are calculated for a reason