Lets talk Baro Correction. . .

[aircooledtechguy]

So I've been running my MS3X for about a year now and have it dialed-in pretty well for cruising around town and out on the hwy. The motor is a 2056 T4 running 45mm ITBs MS3X, Full sequential, LS2 coils +extra MAP sensor for baro correction. all from thedubshop.net. My MPG is around 27-28 mpg hwy and around 25mpg in mixed driving basically driving like I stole it.

However the Baro Correction is not right and I need to get this ironed out before World Of Speed this year. As I climb up the mountains, I go lean so it appears that it's correcting too much. The las time I drove in the mountains I forgot my laptop so I couldn't play with it. I know some of you all live in mountainous states and go up and down on a daily basis. What does your Baro Correction set up like?? Here's my current baro correction window:

BaroCorrection.PNG

So how bad did I screw it up?? Thanks!!

[aircooledtechguy]

So no one is doing baro correction here??? Really???

[subwoofer]

Nope. Used to have "use initial value" enabled until I figured out that it was completely hosing the tune if starting at altitude and driving down. Unless you have a second MAP sensor dedicated to the purpose it's a waste of time.

[aircooledtechguy]

Nope. Used to have "use initial value" enabled until I figured out that it was completely hosing the tune if starting at altitude and driving down. Unless you have a second MAP sensor dedicated to the purpose it's a waste of time.

I do have a second MAP.

[jhoefer]

If you are changing it from 100% across the board, I believe that your baro correction % may actually need to go up as pressure (kpa) decreases. The idea being that as altitude increases and baro pressure decreases, there is less backpressure in the exhaust and therefore airflow through the engine actually increases. Increased airflow necessitates increased fuel. But the correction % would be engine dependent so you are likely just going to have to play with the values until your AFRs stabilize with altitude. Stick 100% in the pressure bin that you originally tuned at (I assume sea level/101 kPa) and adjust the other bins up or down from there.

[Chip Birks]

So no one is doing baro correction here??? Really???

I've had a second sensor installed in my car since the first day it hit the road injected back in 09. That said, I've never really taken the time to make the needed changes to baro to make it totally accurate. I haven't really taken the car out of the valleys I live in/next to.