MoTeC Global Forum

I have I2 Pro with an SDL3. I have the normal inputs, LTC, gps, throttle position, wheel speed etc. I have been using the mixture map that is in the basic template setup but I would like to have a cleaner curve than it generates. Even limiting the throttle position to close to 100% I am seeing lean data points as a result of throttle lift. I have resorted to limiting the data to track straightaways where I know the throttle is fully open there are no gear changes. I then export the data from successive laps to Excel. These curves are clean and present data with little scatter. However, the process is tedious and I am wondering if there is a way to set up something in maths that will do the same thing with far less messing about. Any suggestions ?

Thank You

what version of i2 are you using?
In i2 standard you can tick off the throttle bands below 95-100% this will give you a mixture map using throttle at near 100%. If you are using i2 Pro you can do the same feature but it also has a Gate function where you can gate the mixture map to only work in specific gears if you so wish.

Ty,

I have been using the mixture map and restricting the throttle position. However, there is no accommodation to remove portions of data where there is throttle lift. As a result you get scatter in the AFR trace as a function of rpm. I have been able to clean things up by isolating 4th or 5th gear down the straight and removing the gear shifts manually. That works well but I am pretty sure that there is a better way to do this without that much messing about. I do have pro so I have a lot of flexibility for post processing the data.

BB

Did you try writing a gate function as suggested? I just did this and it looks like it could work.

I created a math channel "Steady_WOT_Gate" with the math expression:

choose(time_valid('Throttle Position' [%] > 98, 1), 1, 0)

What this says is return 1 if Throttle Position > 98% for 1 second, otherwise return 0.

This Gate channel is selected in the mixture map properties and will ignore any data that does not evaluate to the gate condition being >0

I did some testing, and it looks like the function time_valid, becomes true when the condition first becomes true, whereas we want it to be true after the delay period, so I changed my math expression to:

edge_delay(choose(time_valid('Throttle Position' [%] > 99, 1.0), 1, 0), 1, rise)

Which says delay the rising edge of the gate condition by 1 second). That seems to do the trick for me.

Why don't you try that on your data.

David Ferguson
Veracity Racing Data