[tanximing]

When I come back from testing in high altitude areas, I will tell you the results.

[PSIG]

I used Speeduino V4.0 ECU in my two-stroke small Engine, it works well.
I have a question that can this engine work at high altitudes?The Fueling Algoritms is Alpha-N, base on TPS. How can i use the MAP sensor as a constant barometric correction sensor? I want to use this engin work in 4000m+ .

In MS1 EUC,it can set MAP sensor as a constant barometric correction sensor.

Please look at your available settings. In TunerStudio under Tools > Calibrate Pressure Sensors you will find the popup below. Select your barometric sensor type, input pin, and calibration points if yours is not listed. I have not used or tested baro correction for anything as extreme as your situation, nor on A-N fueling, so others may have to jump in here with information; but I believe you would also have to change the code in the sensors.h file. At 4000M on a standard day, your pressure would appear to be in the low 60s kPa, so the code section:

Code: Select all

#define BARO_MIN      87
#define BARO_MAX      108

would need to be changed to something lower in order to allow for that. Perhaps the mid-50s.

Again, @noisymime or other code wizard will have to confirm this, but it would have to be a second sensor with current code, as the Multiply VE by MAP:Baro ratio option is a ratio of the MAP sensor value to the Baro sensor value (not simply baro value in the fuel pulse width calculation). This would mean the MAP would be connected and reading Cycle Minimum values (even if not used for A-N), and comparing them against the Baro sensor value. If there are no other responses to confirm this, then I would suggest bench-testing with the Baro sensor selected to pin A3 (MAP sensor) and apply vacuum to check the impact of the MAP sensor selected as Baro on fuel pulse-width using the Calculations.dash readouts in TunerStudios. Sorry I can't be more helpful as I have not played with the most recent changes to Baro calculations or for conditions such as yours. Please post what you find for future reference.

David

Baro_Sensor.jpg (36.8 KiB) Viewed 3659 times

[usatracy]

I am nowhere near here yet, but I did get the daughter board for the NO2C specifically for the added baro sensor, I am building a v twin for an ultralight airplane, and expected (hoped) that this added baro sensor will solve/manage the lean rich conditions from ever changing altitudes from existing functions already coded into the speeduino and TS ?

[pazi88]

There is baro correction curve in speeduino currently, that you can use: https://wiki.speeduino.com/en/configura ... Correction

[digmorepaka]

I am nowhere near here yet, but I did get the daughter board for the NO2C specifically for the added baro sensor, I am building a v twin for an ultralight airplane, and expected (hoped) that this added baro sensor will solve/manage the lean rich conditions from ever changing altitudes from existing functions already coded into the speeduino and TS ?

If you're running speed density it will (mostly) do it naturally. You can use the baro correction curve to fine-tweak the changes which MAP value itself doesn't get affected by (eg lower back pressure at higher altitude at the same load levels) . If you're running Alpha-N it's a must even with low altitude variations.

[usatracy]

thumbs up thanks all