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killerbee
March 21st, 2009, 03:19 AM
Trying to get on the road to improving LMM economy, and timing is essential in the methods I use. But it seems to be a bit of a mystery.


...different conditions use different tables and nobody that I know of has exactly determined when one is used over the other, although B seems to be used the most, at least at low altitude normal ranges.


Is this still a mystery? Not sure how anyone can effectively tune a vehicle without knowing which timing table is used.



...I haven't seen a tune yet that moved the timing on the pilot. I do

...As far as altitude, I believe that low altitude is seal level up to 3500-4000 feet or so. Medium is from there to 7000-8000 feet (a guess, the words used were "like Mt Everest" which is much higher than 7000-8000 feet!).

Where does this reasoning come from, or observations?

vortecfcar
March 21st, 2009, 01:57 PM
Download build 83 and read the table descriptions.

Nick

killerbee
March 21st, 2009, 04:12 PM
Thanks, I will do that.

killerbee
March 21st, 2009, 05:38 PM
status is build 83. But I don't see any of my questions addressed in it?

???

I still don't see any operational distinctions in the various timing tables.

camcojb
March 22nd, 2009, 03:17 PM
Trying to get on the road to improving LMM economy, and timing is essential in the methods I use. But it seems to be a bit of a mystery.



Is this still a mystery? Not sure how anyone can effectively tune a vehicle without knowing which timing table is used.




Where does this reasoning come from, or observations?

this is an old quote............... :grin: The info I mentioned came from an EFI Live tuning seminar I attended over a year ago. Still don't know the cutoffs for the low/med/high altitudes. The timing tables tell what they're for in the description at the bottom of the page when you click on a certain map. For example, A is used when no pilots are active. B is used when only pilot #1 is active, C is with pilot 1 and 2 active, D is with pilot 1 and pilot 3 active, and E is with only pilot 3 active. I don't believe EFI Live had that description when I posted that info a year ago. Fortunately they are constantly discovering new tables and info, so we benefit.

You can monitor the injection status via the scantool PID - GM.MAINTSEL_DMA

Don't forget the numerous correction tables that interact with those maps.

Jody

killerbee
March 23rd, 2009, 12:53 AM
Hi Jody,

Realizing the LMM is a "work in progress", it is difficult enough to try to modify timing without needing an enigma device. I guess we are stuck with constantly changing timing tables, for now. Would love to be a able to log a single pid that shows which table to refer to.

camcojb
March 23rd, 2009, 02:27 AM
Hi Jody,

Realizing the LMM is a "work in progress", it is difficult enough to try to modify timing without needing an enigma device. I guess we are stuck with constantly changing timing tables, for now. Would love to be a able to log a single pid that shows which table to refer to.

the pid I listed above is supposed to be the one that tells you which table it's using. You apply any corrections from those tables and it should line up.

GM.MAINTSEL_DMA

Jody

killerbee
March 23rd, 2009, 03:36 AM
this is what i get. Nothing that says what timing chart I am on at any given time. You have to do the correlation in your head using logic rules, and its a PIA. :)

camcojb
March 23rd, 2009, 05:49 AM
this is what i get. Nothing that says what timing chart I am on at any given time. You have to do the correlation in your head using logic rules, and its a PIA. :)

you're correct. I just did a log to check, it'll tell you whether the pilot is active or not, and which pilot it is, so from there you have to figure out A through E. Would be nice if it just gave that letter, but it's better than nothing I guess.

Jody

killerbee
March 23rd, 2009, 06:38 AM
It is.

But with it changing constantly, you don't know whether you are coming or going. i suspect somebody will do some kind of logic pid, I just lack the time to figure out the right nomenclature.

rcr1978
March 23rd, 2009, 06:09 PM
Even if it is using table B there are multipliers missing in the tuning software, bad news is your timing will never match what is in those tables. The only way I can even get it somewhat close to what I want is log then add to the areas in the B table, what is in the table will never match your logs so you have to keep fudging things until your happy with it. We are going on 2.5 years for the LMM and things are still very frustrating for tuning and logging but hell it could be worse we could have dodges using someones dinosaur box or bog-ass tuner.

killerbee
March 24th, 2009, 01:17 AM
Thank you to EFILive for a great effort.

GMPX
March 24th, 2009, 02:26 PM
Ok, so what you are saying is that instead of looking at something like this -
"Post Injection #1" Off
"Post Injection #2" Off
"Main Injection" On
"Pilot Injection #1" On
"Pilot Injection #2" Off
"Pilot Injection #3" Off

And then trying to relate that back to Table A,B,C,D,E, it would simply show "Table B" instead?
I can see where you are coming from if that is the situation, still, it was better than flying blind before that PID :Eyecrazy:. It does seem overly complex to have 5 base timing tables. One thing you could do is apply a filter to your logs that only showed data for the Timing map you want to work on.

I'll have to check with Paul on displaying the PID differently as I don't know how to set up PID's like that.

Cheers,
Ross

bballer182
March 24th, 2009, 02:31 PM
B0202 Will help you understand what the ECM considers HIGH, MED, LOW altitude. As with all tables and maps; the ECM extrapolates between the numbers in each cell to get a certain value for any given point in time. So if you look at the table then you will see that the ECM considers you to be in low altitude untill the BARO reads below 13.9 psi and then it does a little math; @13.5 psi it says you get a weighted average between the MED and LOW altitude of 80% LOW and 20% MED.

And im sure you are aware that this table is for the MAF flow rate calculation. But I'm sure that the ECM applies this logic all tables that have tables that are different dependent on altitude.

bballer182
March 24th, 2009, 02:34 PM
Ok, so what you are saying is that instead of looking at something like this -
"Post Injection #1" Off
"Post Injection #2" Off
"Main Injection" On
"Pilot Injection #1" On
"Pilot Injection #2" Off
"Pilot Injection #3" Off

And then trying to relate that back to Table A,B,C,D,E, it would simply show "Table B" instead?
I can see where you are coming from if that is the situation, still, it was better than flying blind before that PID :Eyecrazy:. It does seem overly complex to have 5 base timing tables. One thing you could do is apply a filter to your logs that only showed data for the Timing map you want to work on.

I'll have to check with Paul on displaying the PID differently as I don't know how to set up PID's like that.

Cheers,
Ross


That would be so awesome to display like that. Although it is nice to have it the way it is now too. Any way to have both?

I too was disappointed to see that that PID displayed like that instead of just which table it's using.

killerbee
March 24th, 2009, 02:35 PM
would simply show "Table B" instead?


Yeah, it would be very cool. :cucumber: And it would reduce my motion sickness!

GMPX
March 24th, 2009, 08:04 PM
You guys want to try working on the Bosch ECM's at code level for a day :wallbash:, that will give you motion sickness sitting still.
If I can drag Blacky away from the AutoCal stuff for a moment I'll ask him how I can configure it for both methods, I'm sure it's possible.

bballer182, spot on with the Baro tables, nice description.

Cheers,
Ross

rcr1978
March 25th, 2009, 12:17 AM
Ross, I would love to help you guys out but wrench tosser's are bad with confuser's :throw: :lookaround: :music_whistling_1: I do wish I had enough smarts to write programs and read bosch ecm code then I would not be nagging at you guys all the time about tuning problems.
Keep up the good work.

GMPX
March 25th, 2009, 10:01 AM
Sorry to say this but I don't think there is anything we can do at the moment to show this PID as you want.
Without going in to too much detail, that PID is a series of bits that are set / cleared based on the status of each injection event and this is what we currently show, each individual bit.
To display it as Table A, Table B etc it would need to be configured as an actual value, so if the PID value = 16 then we could show it as Map B, and so on. However, we are only interested in what is happening with the Pilot injections as these are what determines what table the ECM will use. Problem is, within that PID is the status bits for the Post & Main injection too, so all of a sudden you can't say that with a PID value of 16 that Table B is going to be used because if one of the post injections is also on then the value might be something different. As you could imagine all of a sudden there is a lot of combinations to handle.
When the ECM is deciding which table to use it does a few commands to filter out the post and main injection status so it is left with just the pilot status bits, unfortunately we cannot do that in EFILive, however, for Version 8 scantool this is certainly something we can look at, to apply logical equations to PID's before they are processed to the screen.

Cheers,
Ross

killerbee
March 25th, 2009, 10:30 AM
...however, for Version 8 scantool this is certainly something we can look at, to apply logical equations to PID's before they are processed to the screen.

Cheers,
Ross

:grin:

as always, thank you.

Those Germans are crafty.

bballer182
March 25th, 2009, 12:04 PM
Sorry to say this but I don't think there is anything we can do at the moment to show this PID as you want.
Without going in to too much detail, that PID is a series of bits that are set / cleared based on the status of each injection event and this is what we currently show, each individual bit.
To display it as Table A, Table B etc it would need to be configured as an actual value, so if the PID value = 16 then we could show it as Map B, and so on. However, we are only interested in what is happening with the Pilot injections as these are what determines what table the ECM will use. Problem is, within that PID is the status bits for the Post & Main injection too, so all of a sudden you can't say that with a PID value of 16 that Table B is going to be used because if one of the post injections is also on then the value might be something different. As you could imagine all of a sudden there is a lot of combinations to handle.
When the ECM is deciding which table to use it does a few commands to filter out the post and main injection status so it is left with just the pilot status bits, unfortunately we cannot do that in EFILive, however, for Version 8 scantool this is certainly something we can look at, to apply logical equations to PID's before they are processed to the screen.

Cheers,
Ross

I was reading half way through your post thinking to my self what you were actually saying in the last half. Yeah there's got to be a lot of combinations that can end you up and the same value. So it may not be able to be read in realtime in BBL but it would definitely be useful as a filter or custom pid to be used later. Thanx guys:thumb_yello: