Quick EAE question...

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Postby muythaibxr » Tue Apr 15, 2008 11:05 am

Like I said before, the problems at idle mean that the math isn't stable with your settings at those RPMS...

IT means that your added to walls and sucked from walls are too far apart usually.

You can tune the bad behaviors out by adjusting the RPM correction curves for added to walls and sucked from walls.

Generally the procedure I follow for tuning EAE is first get the VE tuned. Proper VE is essential to get this algorithm working.

Second, I turn on EAE, make sure the RPM and CLT curves are at 100% across the board, and then tune 1 RPM or a small RPM range on cruise. I start by tuning slow throttle movement, and work my way up to fast throttle movement. I make sure I'm in a high gear so I don't really accelerate or decelerate that much while doing this.

Then almost invariably, I return to idle and I have oscillations and problems with bucking, off-idle lean-spots, etc... So I tune the RPM correction curves until these go away. Then I do the same thing for full-throttle redline runs with shifts.

Then I stop and let the engine cool off, and start it back up, and try to drive it around. Usually it's OK but not perfect, and I use the CLT curves to get it right.

Finally, I try the "quick blip" behavior for revmatching downshifts. This has typically been the hardest thing for me to get right, and I know why it does this, but have not had a chance to write a lot of code to correct it. If you come to the MS meet this weekend, I'll gladly explain what's going on there. In any case, for quick-blip behavior, I tweak the squirts per cycle, and if necessary turn on lag compensation.

This method of tuning has worked for me every time. Only once or twice I had any trouble, and adjusting ignition timing and other parameters fixed those problems (misfires on quick blips wasn't an enrichment problem, it was a timing problem, etc..)

The reason that EAE has to be "always on" is because it's always tracking the amount of fuel going into and out of the puddle. If I turn off that tracking, and tell it not to change the amount of fuel going into the puddle, then the algorithm just plain won't work. It has to keep accurate track of fuel in the puddle to work, and fuel in the puddle is affected by how much fuel is injected almost in a recursive manner, so if I just track the fuel and don't inject what I'm tracking, the wallfuel numbers will be off, in-turn causing the amount to be injected coming off idle to be off. It just won't work to try to "turn it off" on idle.

Several people gave suggestions for cleaning up the behavior on idle, including adjusting the RPM curves, making sure VE is steady in the 4 points surrounding idle, making sure timing is stable there, and making sure your curves aren't too far apart. If the algorithm isn't mathematically stable, you'll get odd behavior.

Sometimes "bench tuning" can be helpful for this, because you can see the bad behavior without getting pissed that your engine isn't running right. I usually test major changes to those curves on the bench before doing it in the car. I do minor changes while someone is driving around and I'm watching the behavior, but if I want to "try something" bigger, I do it on the bench first.

Ken
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Postby milesinfront » Tue Apr 15, 2008 12:55 pm

Can you post a datalog Ken, so I can use it as a benchmark?

The other thing that makes this hard is the delay between PW and AFR. My 02 sensor is mounted only 5ins from the exhaust valve of No1 cylinder. I've found that the delay on my datalogs is usually 2 samples after everything else. But sometimes it appears to be less. Yet another moving target to further complicate things...

I'm not saying the code doesn't work, but I am saying that it's VERY time consuming to get right...
-1988 325is BMW M52B28 - > MS2 Extra n Spark (60-2 Wheel, Wasted COP, Single VANOS)
-2004 Opel Corsa C / Holden Barina Z18XE - > MS1 Extra n Spark (60-2 Wheel, Wasted COP)
-1976 Triumph Dolomite Sprint Race Car -> MS1 n 'EDIS'd
-1984 C1 2.3 Alpina -> MS2 Extra n Spark (60-2 Wheel)
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Postby muythaibxr » Tue Apr 15, 2008 2:15 pm

I'll see if I can find a datalog, 2 of the 3 cars weren't mine, and were tuned on someone else's laptop.

I may still have a log from my car though.

Ken
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Postby muythaibxr » Tue Apr 15, 2008 3:04 pm

Oh, and I just realized that there's probably no way for you to make it to the MS meet either, so I'll see what I can do about a full explanation of what I think's happening with the quick-blip situation.

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Postby milesinfront » Tue Apr 15, 2008 3:15 pm

Kewl! Sounds great!
-1988 325is BMW M52B28 - > MS2 Extra n Spark (60-2 Wheel, Wasted COP, Single VANOS)
-2004 Opel Corsa C / Holden Barina Z18XE - > MS1 Extra n Spark (60-2 Wheel, Wasted COP)
-1976 Triumph Dolomite Sprint Race Car -> MS1 n 'EDIS'd
-1984 C1 2.3 Alpina -> MS2 Extra n Spark (60-2 Wheel)
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Postby Peter Florance » Tue May 06, 2008 3:23 am

I'd like to bring this thread back up mainly because I have a very similar BMW engine and having been playing with EAE a little.

At this point my tip-in is horribly rich. If I understand Ken, this is something I'll sort out later with RPM correction after I get the midrange correct?

My gut feeling is, for my first step of EAE tuning, I want to set RPM correction curve very low on the low RPM end and 100% across a wider midrange band where I expect to do my Adhere to Walls and Sucked from Walls tuning. I'm thinking this only because my engine hates the amount of low RPM EAE and almost stalls because it's so rich.

Is that reasonable as long as my RPM correction is 100% in the cruise range?

Also, something not clear to me in Step 3a:


Code: Select all
a) The best place to start is to adjust the Adhere-to-walls and Sucked-from-walls curves at a mid-range RPM, with the RPM correction tables at 100% across the board.
Get the engine to respond well under load, with minimal variation in AFR, and get it to behave well during quick throttle blips in this range.


Should I be able to tune the entire Adhered-to and Sucked-from curves with one throttle roll, or I am better to do it piece-wise?

Thanks!
Peter Florance
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81 BMW Euro 528i ESP Car
60-2 Wheel LS2 Coils, Low Z Inj
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Postby milesinfront » Tue May 06, 2008 3:46 am

I gave in.... The EAE code beat me! I'm now running AE. It's a shame as the EAE showed glimpses of brilliance, but after hours and hours of tuning and probably over $100 worth of fuel it just never got there...

I think half the problem was that I was never able to understand what the settings were doing. At first I thought that 'stuck to walls' was when map was going up and 'sucked from walls' was when map was going down, but it appears that BOTH curves are in play the whole time.

I'm not blaming the code. It just was too good for me... I hope you have better results than I.
-1988 325is BMW M52B28 - > MS2 Extra n Spark (60-2 Wheel, Wasted COP, Single VANOS)
-2004 Opel Corsa C / Holden Barina Z18XE - > MS1 Extra n Spark (60-2 Wheel, Wasted COP)
-1976 Triumph Dolomite Sprint Race Car -> MS1 n 'EDIS'd
-1984 C1 2.3 Alpina -> MS2 Extra n Spark (60-2 Wheel)
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Postby Peter Florance » Tue May 06, 2008 3:57 am

Thanks for the reply 'Miles'
What might be helpful in the documentation is a list of what mis-adjusted settings will do.

Example: What if my Adhere to is too large but my Sucked from is ok (at at particular MAP value)? What will be the effect?

When I get EAE running well, I promise to contribute to the documentation.

I can make that promise, as it will probably be a long time before I will have to deliver. :lol:
Peter Florance
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81 BMW Euro 528i ESP Car
60-2 Wheel LS2 Coils, Low Z Inj
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Postby milesinfront » Tue May 06, 2008 4:11 am

I'm sure I'll be corrected if I'm wrong, but my expereince seemed to demonstrate that BOTH Stuck & Sucked must be correct to get the correct AFR. So if stuck was correct and suck was wrong, you'd never know as the AFR would still be wrong.

After spending as many hours as I did to get to what I called the 'half way' point I was pretty sure that 75% of MS tuners will never use EAE. And after spending the same amount of time again, and still not achieving satisfactory results, I quit... :cry:

Is it possible that tuning EAE could be done in a semi-automatic way? Like with Mega Log Viewer and VE tables???
-1988 325is BMW M52B28 - > MS2 Extra n Spark (60-2 Wheel, Wasted COP, Single VANOS)
-2004 Opel Corsa C / Holden Barina Z18XE - > MS1 Extra n Spark (60-2 Wheel, Wasted COP)
-1976 Triumph Dolomite Sprint Race Car -> MS1 n 'EDIS'd
-1984 C1 2.3 Alpina -> MS2 Extra n Spark (60-2 Wheel)
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Postby Peter Florance » Tue May 06, 2008 4:21 am

milesinfront wrote:I'm sure I'll be corrected if I'm wrong, but my expereince seemed to demonstrate that BOTH Stuck & Sucked must be correct to get the correct AFR. So if stuck was correct and suck was wrong, you'd never know as the AFR would still be wrong.



I wondered if maybe these were directional; one worked in increasing MAP and the other in decreasing. I'm hoping Ken will weigh in here.
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Postby wes kiser » Tue May 06, 2008 4:30 am

The whole idea with wall wetting algorithms is at any given point in time, there is a a given amount of the mixture sticking to the walls, and an amount vaporizing back into the charge. Under steady state conditions, this is in equilibrium, and can be ignored (what we have all done with AE since the carburator).

One doesn't adjust "up" and one "down", they are both used to calculate the "delta" between fuel getting squirted in the injector, and the fuel that actually makes it into the engine, and therefor are in play constantly. To truly understand what the code is doing, it helps to understand the physical phenomenon it is trying to model.

Knowing the above, and reading ken's tutorial, it should be possible to achieve good results. When I have tinkered with it, it was ALMOST perfect out of the box, but since my car, tune, and code was always in a state of flux, I normally just left it on TPS AE.
86 Rx-7, swapped to 2.3 ford turbo (BW EFR 6758), ms3/ms3x sequential fuel /waste spark, ls2 coils
88 Tbird 2.3t, Microsquirt Module (PIMP), TFI ignition
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Postby milesinfront » Tue May 06, 2008 4:32 am

I'm fairly sure one balances the other. Hence EAE is ALWAYS active. Ken? Hello? You there? hehehehe...
-1988 325is BMW M52B28 - > MS2 Extra n Spark (60-2 Wheel, Wasted COP, Single VANOS)
-2004 Opel Corsa C / Holden Barina Z18XE - > MS1 Extra n Spark (60-2 Wheel, Wasted COP)
-1976 Triumph Dolomite Sprint Race Car -> MS1 n 'EDIS'd
-1984 C1 2.3 Alpina -> MS2 Extra n Spark (60-2 Wheel)
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Postby muythaibxr » Tue May 06, 2008 10:28 am

Wes's description is correct.

You really have to understand the physical phenomena that are occurring in order to tune it though.

Essentially, the point of EAE (and X-tau) is to ensure that the amount of fuel specified by the VE table actually gets into the engine at all times.

Really what is happening is that there is a certain amount of fuel getting stuck on the walls with each squirt, and a certain amount getting sucked off the walls with each intake event.

a "puddle" builds up on the walls, which I keep track of in the WallFuel1 and WallFuel2 variables (can be seen in a datalog).

The added to walls curve tells the algorithm how much of each squirt is being added to the walls (as a %) per squirt, while the Sucked from walls curve tells the algorithm how much fuel is being pulled off the walls on each intake event.

During steady-state, the amount of fuel entering and leaving the puddle is roughly the same, which gives you a 100% EAE correction %.

During a throttle position change, that equilibrium changes, and you get more fuel entering the walls than leaving it, which means you have to squirt more fuel than normal (steady state) to get the same actual amount of fuel to enter the engine. Once the equilibrium returns, the correction reaches 100% again. During equilibrium, The WallFuel variables will level off. While WallFuel is increasing or decreasing, you'll get more fuel squirted in, or less respectively.

Granted the tuning guide for EAE is a little bit out of date and I need to update it, but the basic steps there should still work.

I find that if you're having trouble tuning it, datalogs are your friend, as well as stim testing.

Tips:

1) Don't try to tune using the old MS method of light stab, heavier stab, heaviest stab, that won't work.
2) Instead, pick an RPM and a gear, get to those conditions, and then move your foot around. Don't get on and off the throttle quickly, get on the throttle, leave your foot in place, wait a few seconds (10 seconds or so should be good) then get off the throttle, and do it again. Make sure you cover your entire MAP operating range (off boost if you're running a turbo). To make things easier, I usually only mess with the added-to-walls curve when I'm looking at pressing the throttle.
3) Take a look at your datalog, in MAP ranges where you step on the throttle and you get a lean spot, increase added to walls, or decrease sucked from walls... if you get a rich spot when you push the throttle, adjust added to walls down, or sucked from walls up. Keep in mind that small changes make a large difference. Adjust a few % at a time with added to walls, and a few tenths of a % with sucked from walls.
4) Also check when you lift the throttle... if it goes lean when you lift, decrease sucked from walls, or increase added to walls. If it goes rich when you lift, increase sucked from walls, or decrease added to walls.
5) This is where stim experimentation comes in handy. Get yourself a syringe (a $3 cooking syringe from the grocery store will usually work fine, though the more airtight the better). Set the RPM on your stim to the same RPM you were tuning at in the datalog, and then experiment with your curves. You should notice that the further apart Added to walls and sucked from walls are, the slower the return to equilibrium. This is where you can spend hours without spending money on fuel. This is where I learned to tune EAE, and learned what to look for and how to fix it with tuning.
6) When you think you have it doing what you want on the bench, take it out for a quick drive, and do the same sorts of things the first time you took it out. Notice how the engine responds to throttle movement, and watch the AFR. Basically your new settings that you came up with on the bench are your hypothesis, and driving is testing your hypothesis. If it doesn't do exactly what you thought it should, go back to the bench and look at your datalog, making smaller changes to get the behavior you wanted.
7) When you think you have things tuned correctly on cruise at that one RPM, repeat the whole procedure off-idle, and at other RPMS, you should eventually be able to converge on settings that work at all RPMS for slow to moderate speed throttle movements.
8) Do the same thing for CLT that you did above.


Keep in mind the following guidelines when experimenting/tuning:
1) On accel, increasing added to walls tells the algorithm that more fuel is getting stuck on the walls (Wallfuel increases due to more getting added to it), and therefore to ensure that the VE-specified amount of fuel gets into the engine, it has to squirt even more fuel. Decreasing the amount of fuel leaving the puddle (Sucked from walls) has the same end effect (but because less is being subtracted from WallFuel, instead of more being added).
2) On decel, increasing added to walls tells the algorithm that less fuel is getting stuck on the walls, which means more of each squirt is getting into the engine, which means it doesn't have to enrich as much to try to ensure that the VE-specified amount of fuel makes it into the engine.
3) The difference between the two curves will affect how quickly the algorithm reacts to changes, and how quickly it recovers.
4) Squirts per cycle has a huge effect on the effectiveness of this algorithm . You should run as many squirts per cycle as possible while maintaining tunability and keeping the max duty cycle down.

The problem with quick stabs is that with small manifolds (relative to engine displacement), a quick change in MAP (and airflow into the plenum) makes it to the engine very quickly compared to engines with large manifolds relative to the engine displacement. It will be tempting to change your EAE curves to get rid of the lean spike that occurs on quick stabs (for those with small manifolds/plenums relative to the engine size). Do not do that! The problem is that for the entire accel event, measured MAP is just behind actual pressure in the manifold, which is a little behind the throttle-position change. The net result is lag between conditions changing, and the fuel changes for those conditions getting into the engine.

To help solve these issues, increasing the number of squirts usually helps. In addition, I have added a TPS-dot/MAP-dot actuated lag compensation, which increases the number of squirts during accel events over the specified threshold. The idea is that if you squirt more often, then changes to fueling due to MAP change get into the engine sooner. For most people using EAE, these two things will be enough to fix the "Quick-stab" problem.

For future codes, I'll be adding an idea that I came up with after reading some papers about model-based engine management. The idea I came up with is that on those engines that have problems, TPS movement always happens before MAP movement. Since the TPS movement actually occurs AHEAD of the change in airflow actually getting to the engine, the idea is to switch to alpha-n during a quick stab. From the VE there (with multiply MAP turned off, and with Al's change to multiply AFR into the pulse-width equation), the VE should be somewhat close to correct. We can use the VE in the alpha-n table to get that change in fuel to the engine sooner, helping eliminate the lean-spike. In addition, since the VE should be close to correct, we can do some math (with knowledge of engine displacement and manifold displacement) to somewhat accurately predict MAP during the fast transient, and then use the predicted MAP to feed EAE.

This will require some more extra tuning... you'll have to accurately tune both a speed-density table and an Alpha-n table, and you'll have to tinker with the size of the manifold vs engine displacement, but I think in the end, the result will be that even people with ITBs can get good throttle response with little or no AFR spiking.

So hopefully now it is evident why EAE *must* always be active for it to work. It's not an accel enrichment algorithm, it's a transient compensation algorithm, which requires keeping constant track of the amount of fuel in the puddle.

Ken
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Postby turbotiger » Tue May 06, 2008 11:13 am

My personal observations and experiences with tuning EAE (Still don't have it down yet) is that I get lean conditions after throttle lift. This I can attribute by logging and looking at the fuel on walls. The puddle is too big and it takes too long for the puddle size to get smaller before the puddle equalizes when the throttle is lifted. This results in the smaller inj pw, and lean afr's until the puddle reaches it's equilibrium size. Increasing my sucked from walls made the puddle size smaller and faster to react. I suppose I could probably also lower my added to walls for the same effect.

With my 2.0L 4g63, I get some pretty good lean tip in conditions. I tried running it at 4 squirts but idle really suffered badly, as the inj pw was too low with my 720cc injectors. In fact anytime the inj pw was that low (1.5 ms or lower) the car would stumble horribly on decel, cruise, etc. Changing to 2 squirts cured most of my idle problems, but caused lean afr's on throttle tip in. I'm still trying to tune that part out.

I've played a little bit with EAE lag compensation, but I seem to have issues with map dot and tps dot. The mapdot noise seems high during regular driving, and tps dot is unusually low when doing large throttle changes. Mapdot noise can go as high as 80, and large tpsdot changes are around 15. Is there a way to increase or decrease the scaling on these?
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Postby muythaibxr » Tue May 06, 2008 12:04 pm

turbotiger wrote:My personal observations and experiences with tuning EAE (Still don't have it down yet) is that I get lean conditions after throttle lift. This I can attribute by logging and looking at the fuel on walls. The puddle is too big and it takes too long for the puddle size to get smaller before the puddle equalizes when the throttle is lifted. This results in the smaller inj pw, and lean afr's until the puddle reaches it's equilibrium size. Increasing my sucked from walls made the puddle size smaller and faster to react. I suppose I could probably also lower my added to walls for the same effect.


Lean conditions on decel can be fixed by decreasing the amount of fuel sucked from the walls. This causes the MS to inject more fuel during those conditions. Increasing sucked from walls will make a lean condition worse because you're telling the algorithm that more fuel is coming from the walls, so it doesn't have to inject as much. Most likely what you were seeing was that your added to walls and subtracted from walls were too far apart, and increasing added to walls gave you a better equilibrium. In that case, I would have decreased added to walls instead of increasing sucked from walls.

With my 2.0L 4g63, I get some pretty good lean tip in conditions. I tried running it at 4 squirts but idle really suffered badly, as the inj pw was too low with my 720cc injectors. In fact anytime the inj pw was that low (1.5 ms or lower) the car would stumble horribly on decel, cruise, etc. Changing to 2 squirts cured most of my idle problems, but caused lean afr's on throttle tip in. I'm still trying to tune that part out.


Yeah, this is one of the problems with injectors that are too large for the engine, which is why I added lag compensation.

I've played a little bit with EAE lag compensation, but I seem to have issues with map dot and tps dot. The mapdot noise seems high during regular driving, and tps dot is unusually low when doing large throttle changes. Mapdot noise can go as high as 80, and large tpsdot changes are around 15. Is there a way to increase or decrease the scaling on these?


You can try adjusting the time mask for MAP sampling, which may allow it to sample at a point in the engine cycle where the MAP is more stable. You can also increase the TPSdot lag factor (try 90-100% if you have not already).

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Postby Peter Florance » Tue May 06, 2008 12:12 pm

Ken and Wes
This is great stuff. I have a much better understanding of where to start.

I'll play with the stim and see what it does.

I'm running 6 squirts alt and have a decent sized plenum; should I tune straight EAE without the lag compensation to keep it simple?

Again once I have it tuned I think I can help with docs. I'm guessing a lot of what Ken just said could be added to the tuning guide.

What would also be nice is some screen shots of logs from properly tuned EAE and maybe some where it isn't tuned correctly and why.

Thanks again!
Peter Florance
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Postby muythaibxr » Tue May 06, 2008 1:03 pm

I'd love to give you those logs, but I can't seem to find any, and right now none of my own cars are running (down for body work etc...)

I'd tune first with lag compensation off, then turn it on after all the other tuning is done if necessary.

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Postby mops » Tue May 06, 2008 7:30 pm

milesinfront wrote:I gave in.... The EAE code beat me! I'm now running AE. It's a shame as the EAE showed glimpses of brilliance, but after hours and hours of tuning and probably over $100 worth of fuel it just never got there...

I think half the problem was that I was never able to understand what the settings were doing. At first I thought that 'stuck to walls' was when map was going up and 'sucked from walls' was when map was going down, but it appears that BOTH curves are in play the whole time.

I'm not blaming the code. It just was too good for me... I hope you have better results than I.


I kinda feel the same...
it's really funny we have the same engine....

as i said i can get it ok for slow to moderate movements. I can live wihout quick stabs, but I cant live wihout smooth gear changes and so far... with eae some gear changes are allright, some are not... esp on load gear changes are really bad (think 50% throttle, quick release, change gear, reapply 50% throttle - results in serious buck...)

increasing number of squirts will not work for me. I got pretty large turbo injectors so idle pw's are low.

long story short, i can get eae close but not good enough to stop playing with it.

I cant play with eae now cos my car is in parts (rebuilding engine)...

Question...
why we can't have normal AE and EAE aswell ? we would have normal eae as it is now, and throttle stomps could be fixed with tps based AE. eae algorithm would know about extra fuel, so it can account for it...
BMW, 1985, E30, 325i, 2-door, 5spd. Lots of custom work. Turbo build in progress: http://www.e30tech.com/forum/showthread.php?t=55733
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Postby Peter Florance » Wed May 07, 2008 7:14 am

I'm not sure I completely get it but here's a throttle roll
Is this what you mean?

Thanks!
Peter Florance
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Postby muythaibxr » Wed May 07, 2008 7:50 am

mops wrote:
milesinfront wrote:I gave in.... The EAE code beat me! I'm now running AE. It's a shame as the EAE showed glimpses of brilliance, but after hours and hours of tuning and probably over $100 worth of fuel it just never got there...

I think half the problem was that I was never able to understand what the settings were doing. At first I thought that 'stuck to walls' was when map was going up and 'sucked from walls' was when map was going down, but it appears that BOTH curves are in play the whole time.

I'm not blaming the code. It just was too good for me... I hope you have better results than I.


I kinda feel the same...
it's really funny we have the same engine....

as i said i can get it ok for slow to moderate movements. I can live wihout quick stabs, but I cant live wihout smooth gear changes and so far... with eae some gear changes are allright, some are not... esp on load gear changes are really bad (think 50% throttle, quick release, change gear, reapply 50% throttle - results in serious buck...)

increasing number of squirts will not work for me. I got pretty large turbo injectors so idle pw's are low.

long story short, i can get eae close but not good enough to stop playing with it.

I cant play with eae now cos my car is in parts (rebuilding engine)...

Question...
why we can't have normal AE and EAE aswell ? we would have normal eae as it is now, and throttle stomps could be fixed with tps based AE. eae algorithm would know about extra fuel, so it can account for it...


Did you read my last post? I've never met a car that I couldn't tune using the method in the last post.

There shouldn't be any real reason to need to enable normal AE with EAE on at the same time.

If you've got slow to moderate throttle movements working, but shifts aren't working well, then you might need to work on the RPM curves in the areas where the shifts are causing you problems (RPM changes a lot during a shift, which means the wallwetting characteristics change too).

Also, lag compensation, which increases the number of squirts during a quick stab or shift or whatever (any TPSdot or MAPdot over the threshold) should be able to cure the quick-stab behavior if the main curves and RPM curves are correct.

You should also make sure that your MAP lag-factor is set as high as possible (up to 100), and you should try experimenting with the map sample time mask... you can tell it to sample right after a trigger up to 50% of the time between the previous trigger and the next. I find that if I set MAP lag to 100, then adjust the time mask until I get the smoothest MAP signal, then slightly reduce the MAP lag factor (down to 90-95) I get good behavior.

The problem is that when you stop using TPS for accel enrichments, you have nothing to compensate for lag on the MAP sensor. TPS accel enrichement compensates by injecting more fuel than it should during a quick stab to compensate for the fact that the MAP-based VE lookup is slow. This isn't possible with EAE, so you have to compensate by making sure that MAP responds quickly, and by doing things like squirting more often (picking up the changes in the commanded amount of fuel sooner) during an accel event.

Bottom line is that if you get everything to respond fast enough, there's no need for normal AE.

Ken
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