EAE strategy question

[sd1nl]

Hi all,

i have been pondering the following question about EAE tuning:

You basically want the total amount of EAE Enrichment to taper down with rpm, to let's say zero at 5000rpm.

Is the way to go to have the "added to wall rpm correction" AND the "sucked from wall rpm correction" taper to 0% at 5000rpm

OR

Is the way to go to to have the "added to wall rpm correction" go to let's say 50%, and the "sucked from wall rpm correction" go to 150% at 5000rpm, thus bringing these values closer to each other and balancing each other out.

Wich of the two is fundamentally right?

Rene

[pit_celica]

On my setup, I didn't need to reduce the EAE correction at high RPM. In my tune, "added to wall rpm correction" and "sucked from wall rpm correction" are all 100% from 4000RPM to redline. I never had any problem going this way. These curves are most useful to stop EAE from correcting the mixture at idle to keep the AFR more steady.

Sam

[sd1nl]

On my setup, I didn't need to reduce the EAE correction at high RPM. In my tune, "added to wall rpm correction" and "sucked from wall rpm correction" are all 100% from 4000RPM to redline. I never had any problem going this way. These curves are most useful to stop EAE from correcting the mixture at idle to keep the AFR more steady.

Sam

I don't think it would hurt, but acceleration enhancement (AE or EAE) is nit needed at high rmp's, so it's just a waste of fuel in your case...

[muythaibxr]

On my setup, I didn't need to reduce the EAE correction at high RPM. In my tune, "added to wall rpm correction" and "sucked from wall rpm correction" are all 100% from 4000RPM to redline. I never had any problem going this way. These curves are most useful to stop EAE from correcting the mixture at idle to keep the AFR more steady.

Sam

I don't think it would hurt, but acceleration enhancement (AE or EAE) is nit needed at high rmp's, so it's just a waste of fuel in your case...

This isn't entirely true, and is very dependent on a number of factors, like what engine, what injectors, how the injectors are mounted, injection timing, etc....

I've never met an engine that didn't need any enrichment at high rpms, but I've seen quite a few need less time-wise.

[sd1nl]

On my setup, I didn't need to reduce the EAE correction at high RPM. In my tune, "added to wall rpm correction" and "sucked from wall rpm correction" are all 100% from 4000RPM to redline. I never had any problem going this way. These curves are most useful to stop EAE from correcting the mixture at idle to keep the AFR more steady.

Sam

I don't think it would hurt, but acceleration enhancement (AE or EAE) is nit needed at high rmp's, so it's just a waste of fuel in your case...

This isn't entirely true, and is very dependent on a number of factors, like what engine, what injectors, how the injectors are mounted, injection timing, etc....

I've never met an engine that didn't need any enrichment at high rpms, but I've seen quite a few need less time-wise.

Fair enough. I agree here. But nevertheless there should be some kind of tapering down. Do you know if I should taper both SOW and AWW down, or should I let AWW taper down and SOW taper up so they are equal at high rpm's

[muythaibxr]

You do not need to taper either down. Those curves control what the code thinks is getting onto the port walls with each squirt and what is coming off the walls with each intake event. You should just adjust so the transient brhavior is correct.

[sd1nl]

There is more wall wetting when the engine is cold. This should be accounted for in the calculations. If you have a flat clt correction curve this won't work. Or am I wrong here?

[16vboost]

Taper down? No. Don't think of the curves as "amount of correction". Instead think of them as describing what would be happening to the puddle with changing MAP. For me I think of a puddle of fuel, water, whatever in a pressure chamber. When you pull a vacuum, the fluid will tend to evaporate more. When you pressurize the chamber, it will tend to evaporate less. So Added to walls goes up with pressure and sucked from walls goes up with vacuum.

So what causes the correction? Wall Fuel. Or more accurately, changes in wall fuel. Log wall fuel and EAE correction when tuning and you'll see what I mean. If you're going from a low wall fuel condition like over-run (low pressure, low added to walls, high sucked from walls) to a high wall fuel condition like full throttle (high pressure, high added to walls, low sucked from walls) you'll get >100% EAE correction. Again its the change in puddle that causes the correction.

So back to your original post. Keeping the ATW and SFW curves horizontal after a certain point will cause no changes in wall fuel and no correction. Here are my curves for reference.


https://lh3.googleusercontent.com/-3PPs ... AE-MAP.JPG

Once you tune the two main curves you can start with the RPM and CLT correction curves.

-Alex

[sd1nl]

Taper down? No.

I was merely talking about the curves tapering down in a graphical way. Maybe the curve going up or down is a better way to say it.

Anyway, my EAE works fine, Just when I do the calculations manually the time to go back to a steady state is much shorter

But your description is accurate, and your AWC curve looks a lit like mine.

[muythaibxr]

Taper down? No.

I was merely talking about the curves tapering down in a graphical way. Maybe the curve going up or down is a better way to say it.

Anyway, my EAE works fine, Just when I do the calculations manually the time to go back to a steady state is much shorter

But your description is accurate, and your AWC curve looks a lit like mine.

Provide an example of your math vs the MS.

[sd1nl]

I will try to work it out in a presentable manner this week