2 BAR GM MAP 12615136 values

[y2konyxss]

Hello everyone,

Im trying to understand the MAP sensor settings for a 2BAR SD tune.

I have installed a GM 12615136 into my LS1, upgraded to the HPT 2BAR OS

I have tried to get the MAP dialed in and having no real luck.
What i am trying to understand is how people arrived at these numbers.

My understanding is when you have the car off the MAP should read from 100-102KPA

Right now mine is reading 99KPA, I know that’s pretty close, will that be close enough is the first question. Next question is when I upgrade to 2 BAR it automatically changed my values to 200KPA and offset of 8
I understand the Offset of 8 since that is the KPA reading for that sensor a 0Volts.
But what I don’t understand is why does the sensor only goto 200KPA at 5Volts when according to the technical specs its approximately 208-210 KPA at 5Volts

Can anyone explain to me why we are recommending?
200
And offset of 8.

Or is this just a good starting value and we should be modifying these values until we read 101 KPA with the car off.


My current values are:
208
And offset of 8.33

Am I out to lunch or is this more accurate?

[5_Liter_Eater]

http://www.hptuners.com/forum/showthread.php?t=37417

[y2konyxss]

I believe when I used 200/8 it was reading 95 on the HPT
I verified my area was 102.5KPA yesterday.

So in theory i should be adding to the offset value until it reaches my current area's Baro does that mean the low end idle vacuum values will be out of whack?

I know the low end and high ends of the sensors have the most % of error.

I was searching the forum yesterday and never could find an answer that completely solved my problem.

So maybe try 200/10 and so on until i reach desired values?
just seems strange that its so far off.
thats why i reviewed the technical specs of the sensor.

[5_Liter_Eater]

Seems odd that it would be off that far. The best way to get it accurate would be to use a mitivac that does vacuum and pressure and see what the voltage values are taking data points in vacuum and boost.

[Russ K]

Never seen more than 94 kpa key on, engine off in the Regina area. The 2 bar map linear should be 200 and the offset should be 10.33.

At sea level, I've seen 102 kpa key on, engine off.

Russ Kemp

[y2konyxss]

Hey Russ, I'm surprised that would be the case when our baro is 102.5. Wouldn't you want the two to match? Either way in that case would you set the boost enrich to start at 95kpa?

[Blades]

From what I've seen, baro sometimes can just be MAP readout upon key on, engine off.

Find someone with a Motorola Xoom tablet - it has an onbaord baro sensor. very accurate.

[Russ K]

Hey Russ, I'm surprised that would be the case when our baro is 102.5. Wouldn't you want the two to match? Either way in that case would you set the boost enrich to start at 95kpa?

The weather stations report mean sea level barometric pressure. That is what the air pressure would be if at sea level. It's only useful for predicting weather changes.

I think there were some discussions about the delay in the boost enrich table, and to just set your PE table as desired.

Russ Kemp

[y2konyxss]

Thanks that's some useful imformation I was not aware of. We are around 94kpa since we are approximately 2000 ft above sea level here.

http://http://www.engineeringtoolbox...ure-d_462.html