okay, got the boost sensor/wideband reading issues almost nailed down. i am VERY math illiterate and i am having issues "seeing" this in my head.

Motorola MAP sensor: absolute pressure sensor charactoristics
2.9psia = 0v
36.3psia = 5v

in my LM-1 software i input the "xx psi = xx volts" parameters so, being an absolute sensor the 0v needs to have atmosphereic pressure (14.7psi) subtracted from it(ie: -14.7psi = 0v), so my question is this: following that logic, since the sensor charactoristics are 2.9psi @ 0v, do i need to take an additional 2.9 psi from that giving me -17.6psi to = 0v, or the other way around getting me -11.8psi to = 0v? whatever that answer is, i would take that amount off the top values as well, right? so 36.6 @ 5v would be 36.3 minus either 17.6 or 11.8 to give me "corrected" max pressure at 5v.

thanx...!

Just substract 14.7 from both numbers ... 2.9-14.7 and 36.3-14.7

DOH!!!!!!!!!


(sheepishly... thanx)

I basically had this conversation with Tim and came up with this but I thought I'd post it for the rest of you guys.

Output voltage = (((ManiPressureInKPA - 20) / (250 - 20)) * (4.9 - .2)) + .2

...which can be reduced to

Output voltage = (((ManiPressureInKPA - 20) / 230) * 4.7) + .2

The (250 - 20) is the pressure range and you have to -20 from your manifold pressure to account for the fact that the sensor doesn't see anything till 20kpa. The (4.9 - .2) is the voltage range. And the +.2 is the voltage start.

0 pounds of boost is gonna be ~1.83v
max boost is gonna be ~22 pounds of boost - and it should hit 4.9v at that point


95 Eclipse RS : 5 speed
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^^^^^^ is THE MAN!!!!!!!!!!!!

thanx jim