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-   -   EGO Settings (https://www.miataturbo.net/megasquirt-18/ego-settings-69643/)

wolfram 11-25-2012 04:09 AM

EGO Settings
 
2 Attachment(s)
Couldn't find a post on EGO settings. Should we leave this as default (from the base map on a MSPNP)? Have a 1.6 with a pnp and not getting very good gas milage. Autotune has done its job (and if anyone is sick of my frustrated posts, i have several posts on here about my black exhaust crap!). I am going to recalibrate my Innovate LC-1 tomorrow, as i think i may have some incorrect AFR readings...

Here is what i have. I live at altitude, so i have it in open loop for my idle, as the temps and elevation changes drastically during my daily drive. I also have it running below 115Kpa since its only a little bit of boost. My main question is about the events per step, auth percentage, etc settings. I think my base map had 16, but read somewhere that 28 or 29 was good for a 4 cylinder.

hustler 11-25-2012 09:04 AM

1 Attachment(s)
https://www.miataturbo.net/attachmen...ine=1353852259

Lincoln Logs 11-26-2012 10:25 AM


Originally Posted by hustler (Post 953005)

I've always left the authority at 8%, I was under the impression if your VE map was well tuned you do not need to give EGO that much authority.

one-niner 11-26-2012 10:35 AM


Originally Posted by Rokomis (Post 953200)
I've always left the authority at 8%, I was under the impression if your VE map was well tuned you do not need to give EGO that much authority.

That's my understanding too. But then again, if it's not needed, I suppose it won't get used, so why cap it in the first place? Failsafe limits in case of a WB sensor going bad? Or is there another reason?

- Tom

hustler 11-26-2012 11:05 AM


Originally Posted by Rokomis (Post 953200)
I've always left the authority at 8%, I was under the impression if your VE map was well tuned you do not need to give EGO that much authority.

You're right, but when it's 107*f outside and you're parked in traffic with 205*f IATs in some sort of outer ring of "super heat soak hell", you may need more than 8% in traffic.

Braineack 11-26-2012 12:09 PM

plus he's using PID corrections which will keep the target much better.

Lincoln Logs 11-26-2012 12:42 PM


Originally Posted by one-niner (Post 953203)
That's my understanding too. But then again, if it's not needed, I suppose it won't get used, so why cap it in the first place? Failsafe limits in case of a WB sensor going bad? Or is there another reason?

- Tom

That is a valid point.


Originally Posted by hustler (Post 953213)
You're right, but when it's 107*f outside and you're parked in traffic with 205*f IATs in some sort of outer ring of "super heat soak hell", you may need more than 8% in traffic.

I can definitely see that, it' something I experienced in the heat this year. I'll start playing with this more.


Originally Posted by Braineack (Post 953236)
plus he's using PID corrections which will keep the target much better.

This is something that I need to do some research to understand better. I am not utilizing this function on my MS. Does this setting help with small +/- .2 fluctuations of the AFR under constant load?

Braineack 11-26-2012 12:53 PM

no, you shouldn't really be in closed loop under load.

hustler 11-26-2012 01:05 PM

http://msextra.com/doc/ms3/Idle_Control.html
The following basic steps should be used for tuning the PID controller gains:

Zero all the gains - Set all the gains to 0%. This is so that the effects of tuning the I-term in the next step are not confused with the effects of any other setting.

Tune the Integral (I) gain -
The Integral gain is the only term that controls whether the code actually reaches its target. Higher values for Integral gain will result in the code being able to get closer to the commanded target; however, a value that is too high will result in oscillation. The easiest way to determine a good value for the I term is to keep increasing it until oscillation occurs, then slightly lower it. If this value is increased to 200% without reaching a point where oscillation occurs, then the RPM with valve opened setting can be decreased as far as necessary, and the open duty/steps setting and closed duty/steps setting can be made further apart to make the PID loop more sensitive.

Tune the Proportional (P) gain -
After tuning the I gain so that the RPM reaches the commanded target without oscillation, the P gain can be tuned. The best way to tune this is to set it as high as possible without getting any oscillation. After setting this, try turning on the air conditioning or other accessories that normally lower RPM or increase load. When these accessories are turned on, the RPM should dip a bit then recover (the valve position should increase significantly). Using longer PID ramp to target times can also make it so that when the PID algorithm engages, a higher P gain can be set without causing oscillation.

Tune the Derivative (D) gain -
For most users, use of the D gain should not be necessary. It substantially dampens the response of the loop.

hustler 11-26-2012 01:07 PM


Originally Posted by Braineack (Post 953244)
no, you shouldn't really be in closed loop under load.

Unbelievably good AFR target achievement with the PID control on my daily.

Braineack 11-26-2012 01:22 PM


Originally Posted by hustler (Post 953249)
Unbelievably good AFR target achievement with the PID control on my daily.

is that the EGO settings you posted?

hustler 11-26-2012 01:41 PM


Originally Posted by Braineack (Post 953250)
is that the EGO settings you posted?

Yes

Braineack 11-26-2012 01:49 PM

you dont have EGO enabled at full load.

it's off above 75% TPS and/or 90kPa.

hustler 11-26-2012 02:29 PM


Originally Posted by Braineack (Post 953256)
you dont have EGO enabled at full load.

it's off above 75% TPS and/or 90kPa.

Did I miss a question or something?

Braineack 11-26-2012 02:30 PM

i dunno. i like turtles.


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