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-   -   ITT we discuss EAE on MS3 (https://www.miataturbo.net/megasquirt-18/itt-we-discuss-eae-ms3-83753/)

arghx7 06-24-2015 12:32 PM

ITT we discuss EAE on MS3
 
As I mentioned in ryephile's and other threads, set injection timing calculation to end of squirt (sequential). Begin with a global value in the entire map. I choose 300 btdc. Sweep in 20 degree increments, advancing first and retarding, about 120 degrees in both direction. Subjectively assess smoothness, look at tendency to misfire, change in afr, etc.

Then you can try narrowing down to specific speed load areas if you want to. There's more than one way to do it. A dyno helps.

With fixed end of injection the start of injection is calculated based on injection pulse width converted from time duration to crank angle duration. So the ecu figures out when it needs to start firing to deliver the specified injection duration and end at the specified value from the table.

18psi 06-24-2015 12:51 PM

I'm going to start doing just that (hopefully soon) and will post up the conflicting injector timing maps I see from Brain/Rev/DIYautotune in an attempt to figure out the reasoning behind the numbers. Just to understand it better.

arghx7 06-24-2015 03:31 PM

ITT we discuss EAE on MS3
 
I've seen some of these maps floating around and I'm guessing a lot of them were set to start of injection rather than end of injection.

18psi 06-24-2015 07:37 PM

https://www.miataturbo.net/megasquir...1/#post1243424

Speed Junkie 05-18-2016 09:30 PM

I have a BP with MSPNP, latest firmware, and ITBs. I've been struggling with EAE on and off for a couple of years now and no matter what approach I take to solving this problem, I end up at the same comclusion. The code/algorithm is just not structured for the fast map changes of ITBs. At best I have to "work around the problem" by using extermely low values that cause EAE to act erradically.

The main problem is that EAE (the value visualized at the EAE gauge that we're familiar with) does not return back to the 100% position (during throttle off conditions) unless map starts to go back the other way. This might be fine with a plennum-type manifold, but not with ITBs as the pressure pulses simply travel too quickly.

For example, if I let off the throttle to shift and EAE drops to say 70% (so 30% less fuel), when I step back on the throttle, EAE FIRST hast to get to 100% EAE before even going past 100% to count for the increase in throttle. Of course I get a huge lean spike and annoying hesitation before the gauge even reaches 100%. Then an annoying rich condition for a good 2 to 3 seconds after because EAE is finally going past 100% but just hovering there instead of quickly returning back to 100%. Add to that the fact that you've got x ft of vacuum lines that the pressure pulse has to travel through to get to the map sensor. vacuum lines that are already taking pressure downstream from the throttle plates.

So what I've had to do is just use really low SfW and AtW values to keep EAE relatively close to 100% during throttle movement. I've also tried everything from high wall values and low rpm correction values and vise versa. As well as making sure the wall values weren't too far apart. Nothing I tried would get rid of the fact that EAE hovers in either -100 or +100 conditions AFTER map has stopped changing instead of quickly returning to 100%

I've even tried running SfW to 0 at the very bottom of my map range so that it snaps back to 100% during throttle off (shifting) but then that creates an annoying -100% EAE "snap" when you're getting BACK ON the throttle. After dealing with this I've wondered allot about how expensive ECUs like Motec control transient throttle movement. It's not like ITBs are a new thing

DNMakinson 05-20-2016 06:38 PM

SJ. Please post you msq and a log of the throttle changes. It will likely be next week, but I'll look at them, and see what I can see. I'm interested in what your total wall fuel looks like. Generally, if ATW and SFW are too far apart, return to 100% will take longer.

Meanwhile, did you approach EAE in the manner we suggested? And, are you using throttle based AE at all?

I'm not an expert, but something might become obvious if I have more than a description to go on.

one-niner 07-27-2019 03:05 PM

I know this is an old thread but it's still the best one on EAE I've found (please drop links if you know of an even better resource apart from the diyautotune.com guide and manuals at msextra.com).

@DNMakinson and 18psi: Massive thank you for contributing the stuff above! Are you still running the same settings/maps? Any additional learning about EAE worth sharing?

Cheers,

HowPrayGame 07-27-2019 04:07 PM

This thread is more recent and is also good to reference

DNMakinson 07-27-2019 05:55 PM


Originally Posted by one-niner (Post 1543608)
I know this is an old thread but it's still the best one on EAE I've found (please drop links if you know of an even better resource apart from the diyautotune.com guide and manuals at msextra.com).

@DNMakinson and 18psi: Massive thank you for contributing the stuff above! Are you still running the same settings/maps? Any additional learning about EAE worth sharing?

Cheers,

Mostly minor tweaks.


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