MAP sensor calibration

[L31Sleeper]

What is the factory LMM MAP capable of reading ??

[L31Sleeper]

Anybody know what the MAX pressure the stock MAP is capable of reading ??

[JoshH]

Should be 52ish PSIA.

[L31Sleeper]

vs PSIG ??

[bballer182]

I would think that PSIA and PSIG would be the same in this case.

[JoshH]

vs PSIG ??

Yes. The absolute highest reading is somewhere around 52, but that is including atmospheric pressure.

I would think that PSIA and PSIG would be the same in this case.

Only if you are in space or somewhere else where there is a very high vacuum.

[joecar]

I thought PSIA = PSIG + BARO


anywhere where BARO is zero will allow PSIA to equal PSIG.

[L31Sleeper]

So what do you do if you want to run 80 PSIG ??

[JoshH]

I thought PSIA = PSIG + BARO


anywhere where BARO is zero will allow PSIA to equal PSIG.

I'm not sure if this is directed at me or bballer, but a vacuum is a lack of atmospheric or barometric pressure.

So what do you do if you want to run 80 PSIG ??

Get an aftermarket gauge. There have been a couple of people who have worked with replacement sensors that are good up to 100 PSIA and rescaling the sensor, but last I heard they were having problems with it. It was also on LB7 and LLY motors. I don't think LBZ and LMM motors have access to the boost sensor scaling in EFILive.

[joecar]

I'm not sure if this is directed at me or bballer, but a vacuum is a lack of atmospheric or barometric pressure.

I was questioning bballer and affirming your reference to space (PSIA = PSIG = BARO = 0).



PSIA and PSIG are generally defined to be related by PSIA = PSIG + BARO

(nevermind me, I'm just sweeping thru all the threads)

So has anyone explained why MAP isn't equal to BARO at sea level (I'm curious to know)...?