A few days ago Scheides and I were discussing what value we should use in EvoScan to have a properly calibrated MAP sensor for logging boost. We were looking at the atmospheric pressure calculators and it basically told us for our local elevation we should be using 14.23 (sea-level is 14.7); this value of course will vary slightly day-to-day so please keep that in mind. Well yesterday I noticed that with my ignition on, EvoScan connected, but engine off my JDM MAP sensor was not reading zero. Well, I did some quick head math and realized if I changed that mentioned value to equal 14.3 I would be reading about zero. Plugged in the new value and my MAP sensor was registering -0.01...close enough for me! I'll check it every so often as weather conditions/seasons change, but I thought this was an extremely quick and easy way to calibrate it rather than doing all the dumb elevation math.

 

Well I just got **** and adjusted the value so my JDM MAP sensor now registers 0.00000 when the engine is off I'm curious as to how sensitive it is to elevation changes so I'm going to drive up a small hill and see what it registers then. Also, as far as I can tell, heat does not affect its readings (which is good and proper I believe).

 

thats how i have always calibrated it. Never did any math just logged the car off and change the value . And its pretty sensitive atleast with mine its very sensitive