Jump to content

any one use a omni 4 bar map sensor


Recommended Posts

I have scaled two different MAP sensors for LGT. GM 3BAR and AEM 5BAR. You need to rescale for the sensor. Your ECU uses a different scale than the STi. You need some data to figure the line and slope. The math is easy. I put the equations in my write up on the GM 3BAR is the performance mod section. Get a cut sheet for the sensor and I can do the scaling in minutes. Boost gauge is just to verify. If MAP sensor reading is too far from Atmospheric pressure sensor reading pre start up, car will not start. Be careful.
Link to comment
Share on other sites

I bought one for my legacy...just awaiting delivery...I have no idea how to scale or tune, so that will be up to my tuner to take care of...


m_sprank...if you could do the scaling and post up that would be awesome, I'll pass it on to my tuner incase he needs it...

Link to comment
Share on other sites

The cutsheet on the sensor shows a voltage of 0.563 at 50kPa. It shows a voltage of 4.8 at 400kPa.


So, if Y = MX + B, then

400-50 = 350kPa or 58-7.25=50.75psi



4.8v - 0.563v = 4.237v difference

350kPa / 4.237v = 82.606kPa/v or 50.75psi / 4.237v = 11.978psi/v

400kPa = (82.606kPa x 4.8v) + B or 58psi = (11.978psi x 4.8v) + B

B = 3.491kPa or B = 0.5056psi


82.606kPa = 11.981psi this is your multiplier or 11.978psi this is your multiplier

3.491kPa = 0.5063psi this is your offset or 0.5056psi this is your offset


Offset on this equation is a bit odd. Multiplier is very stable. Here is the reason. Depending on when you convert to psi the offset changes.



The average of the two offsets is 0.5060, I would use this.

Link to comment
Share on other sites

  • 4 months later...
  • 7 months later...


This topic is now archived and is closed to further replies.

  • Create New...

Important Information

Terms of Use