NefMoto

This is the place holder for the start of the basic ME7 Tuning How To.

So far some things I plan to cover are...

1. How to adjust boost.
2. How to adjust rev limit.
3. How to adjust for larger injectors or higher base fuel pressure.
4. How to adjust WOT fueling.
5. How to adjust part-throttle fueling.
6. How to make timing adjustments.
7. How to eliminate all emissions tests, but still pass OBDII tests.

Stay tuned for when I find some time to post info, or start posting info yourself if you think you already know how to do this, or something else you think is useful.

Also, please let me know if there is something specific you want covered.

How to scale for different size MAFs

How Correction factors and Knock voltage are related and how to use them for timing adjustment.

Also some basics that are really necessary for tuning:

How to log pulls. 
How to make graphs of logs.

This would be a VERY useful post  ;D.

BR.

Original post is from October, but i can't see a link/info - was it ever posted?

Rick

Sorry everyone. This thread has stalled as I am trying to get my flashing software released.

I am hoping to refocus on ECU tuning again once the flashing stuff is squared away.

any idea when that will be ;)

michelangelo didn't rush thru the sistine chapel and we all know how that turned out, let the artist take his proper time with his masterpiece so that we may all enjoy it. 

The first release is done aside from some security code problems. If I release now, you can only flash a 2001 mbox ecu. I want to give it a few more days to see if I can get the security algorithm working for more ME7 ecus.

i have an mbox i would love to read the file on. i have 2 ecus both with custom flashes. 2 aftermarket chipped ones as well

The next software release of the NefMoto flashing tool will support reading ECUs. Look for the update next week.

bump for this thread... i have read through many of the posts on the forum and now i've opened up an m-box bin. file in tuner pro... not sure how i find these addresses like KFMLDMX in hex...
lol at me the total noob.

i just had to look a little harder.
so i found the xdf for an mbox which is what you want, not the bin. and now i see the list addresses which contain the maps i need to look at. [url]http://s4wiki.com/wiki/Tuning[url]

Hi guys.

I have done something similar for the www.tt-forum.co.uk which is now in draft form and being reviewed by someone from another tuning forum.

Because of my lack of a working knowledge of Bosch Motronic ME7 tuning, I have had to base it on the S4 wiki and supplement with actual maps from the Audi TT 8N 225 BAM and BFV and sections of the translated funktionsrahmen.

I am hoping the guy reviewing it will be able to offer enough assistance that I can significantly reduce, or even eliminate my heavy reliance on the S4 wiki structure. I am happy to make it available here in due course, but might be a good idea to pool resources if you would like sight of it Tony?

Doug

I would like to see it please.

O.k., but I want to see what the reviewer has to say first. Significant revision to the technical content might be required.

Also, even though I have illustrated, edited and augmented the S4 wiki, it was intended to give TT Mk1 owners a flavour of which maps are important and which are changed by tuners. It's not structured or written as a 'how to' as such. I have a pretty basic flow chart which sort of summarises the funktionsrahmen modules a tuner might consider reviewing.

TTQS

Please post it here whenever you are comfortable. I am sure there are lots of people here willing to give feedback.

If you would like private feedback prior to publishing, I am sure anyone on the forum, myself included would love to help critique it.

All ME7 tuning should be about 70% the same I would say, depending on what sensors and actuators the specific engine has. Ultimately at the end of the day, ME7 is based on controlling load, and so we are all tuning load control matter which ME7 engine it is.

Hi Tony.

My reviewer has not come back to me with any detailed comments so I presume his initial response was all I'm getting.

I have left the TT Forum now but still have an interest in making some of this content available. I'll PM you the link to the file Tony if you want to have a look at it. Perhaps between a few of us, we can knock it into better shape as a how to?

Regards.

TTQS

This sort of thing is precisely what a wiki is good for. Sending a word document back and forth between 3 or more people is almost never productive..

Can't argue with that. Well, here goes nothing. [Links now replaced with attachments].

Comments welcome, but please don't savage it because it was conceived as a very basic guide for non-tuning types to get a handle on the topic (and, as I said, is based heavily on the S4 wiki) anyway. I had prepared all the material into forum free text format (many hours spent using Excel macros, etc. to format the tables) so it could be posted up once reviewed and edited.

The main document at Revision 1 (23rd September 2011)
Understanding ECU Remapping The Audi TT 1.8T Variants - Bosch Motronic ME7.x (Rev 1).pdf (1.09 Mb).

Supporting information in MS Excel 2003 workbook:
Attached to post

ECU Files:
Audi TT 1.8T ARY 180 PS 8N0 906 018 BR 0261206439.
Audi TT 1.8T BAM 225 PS 8N0 906 018 CB.OLS
Audi TT 1.8T BFV 240 PS 8N0 906 018 CA 0261208086 375111.bin
Attached to post.

Translated funktionsrahmen modules
Any funktionsrahmen modules I have translated manually are on the Nefmoto wiki and on this stickied thread:
http://nefariousmotorsports.com/forum/index.php/topic,555.0title,.html

TTQS

A truly outstanding document! Really, a fine job distilling information.


I don't mind people using the s4 wiki as a reference, but in return, I'd love more active participation in refining the s4 wiki ONSITE :)

Thank you TTQS, this is a massive leg up for me. your opening paragraph sums up why I'm here I think.

Just finished reading!

A truly staggeringly awesome document!

One (very minor) comment though on something that stood out.


I am convinced this is an unintentional "bug" in ME7. I can't think of a single good reason why you should EVER let the set point be over the heighest possible measurement..


A dramatic understatement :)

O.k. guys, thanks for the comments. It will be interesting to see how we progress from here.

I accept the comments regarding the S4 wiki, but I am not sufficiently knowledgeable or experienced to modify or contribute to that body of knowledge. Not at least without a collaborative effort.

Just to illustrate the gulf between amateur tuning and professional ECU calibrators, the person I originally sent it to commented:

"There are many errors which will be too time consuming to correct".

The tuning for their company is done by a third party to their specification he tells me, but he himself has a very good working knowledge of Bosch Motronic tuning... You see why I was disheartened?

Regards.

TTQS

Yup. This is why (non-bosch) professionals are useless in the current ME culture. Their shit doesn't stink, they don't have "time" to help you, you are "too stupid" to do it yourself, and you are "stealing" from them.

None of them have *ever* actually TRIED to write a document, from scratch, that others can read and learn from. They may have a million little factoids in their head, but absolutely no ability to convey it usefully to anybody else. I understand your pain... which is why I'm saying... GREAT JOB.

Obviously it has mistakes and outright falsehoods.. I know for a fact s4wiki does, but it is the best I could do with what I've got. As I find the problems, I try to correct them, but I can't think of a single instance where a "knowledgeable" person has actually tried to help in any real way other than "you're wrong. I can't tell you why, its a secret" or "its too complicated".

I am just glad somebody other than me has tried to write such a document!

O.k. Thanks. Comforting words actually.

I accumulated over 2,000 posts in about two years on the TT Forum but ultimately resigned due to work and family commitments. It was a bit of a shame that I felt the need to do that before publishing this effort, but hey. So it goes.

This forum seems pretty good so far. Not as many members and leechers which can only be a good thing. It would be a bit hypocritical to resign from one forum and then start haunting another though!  ;D

I guess I have to watch what I say because before I approached the pro tuner to have a look at this article, he caught up with me asking questions while researching on www.chiptuners.org. It was always going to be a big ask for him to help me out though, but yes Nyet, I share many of your sentiments. ;)

I mean, if they tell us how EGT regulation works, do they think that anyone with a funktionsrahmen, a KWP2000 suite and a laptop will wake up the next morning a brilliant professional tuner? I think not.  ;)

I could, of course, have simply flashed off the commercial remap from my ECU and used that as a basis for the analysis and I probably would have made better progress. But I didn't because I have some integrity and the work is probably worse off for it.

TTQS

i will work through your document in the next days .. as my native language is german it will take a bit longer for me.

All i can say is you got my full respect on doing such a document.

But you have to understand professional tuners too.

They pay about 100.000 € to learn how to remap ...

So just hope it won´t come into the wrong hands and no ebaysuccker will sell it

A freely available document has an ebay value of 0.

Nobody sells RFCs.

I am working my way through the document and adding comments. It is slow going though when I have to write a comment on every paragraph. No bad comments, just pointing out areas where the discussion is too vague. Great work so far with what I have read.

Hi Tony.

That sounds encouraging. You're probably giving it the level of attention I expected and needed from the first reviewer.

If you all want to feed back comments to me (PM me and I'll send you my e-mail address to which you can e-mail a marked up version), the best way forward might be for me to revise it based on Tony's suggestions and others areas of commonality then republish it as Draft 3. That could be a few weeks away but I'll do my best.

Once most people are satisfied and/or have contributed their own material, I will transfer it to forum free text for publication here. No reason why the S4 wiki can't be updated in parallel either I guess.

If anyone has fully-defined .OLS files for other Motronic ME7.x equipped vehicles like the 225 BAM one I have been using, I'm sure it would be helpful to bring those under this umbrella too. I obtained some files in a VAG set while researching the article, but obviously I only needed the Audi TT 8N ones. Four (including the 1.8T BAM 225PS file in my supporting information) are posted up here:

http://www.nefariousmotorsports.com/forum/index.php?topic=467.0title=

BTW. I used to be a technical author working on nuclear industry safety cases, so I'm used to technical documents bouncing back and forth between verifiers and independent safety assessors.  

TTQS

Doug, if it isn't too much trouble, PLEASE give me a heads up on specifics you find are wrong in the S4wiki.

Thanks in advance, I really appreciate it.

Nyet, you seem to be misunderstanding me.

I didn't find anything wrong in the S4 wiki. In fact, it seemed to be quite a sound information source. I don't have the knowledge or experience to spot errors or omissions or else I would have corrected them myself in my own document. I don't even have knowledge of the S4 2.7 V6 biturbo; my experience is with the 1.8T BAM and BFV variant motors. The reason I sought a peer review was because I have no working knowledge of Bosch Motronic ME7.x.

All I can tell you at the moment is that the professional tuner that had sight of Draft 1 commented that there were many errors, but did not give me any specific feedback. He did not say whether the errors were in the S4 wiki or my interpretation or translation of the funktionsrahmen information.

That is why I am here, so that guys like Tony or anyone else with a working knowledge of Bosch Motronic ME7.x tuning can turn my draft article into a 'How To' for tuning these ECUs. Then all those with a vested interest can take away what we want for our own purposes. Yours being the S4 wiki...

Does that help clear things up for you?

TTQS

Thanks, this was a great find. I

Sorry, I didn't mean for it to come out that way. I'm just super worried that people are taking the s4wiki information as completely canonical, and I am always looking for improvements, since almost all of it predates my reading of the Funktionsrahmen and is derived not only from rudimentary logging and empirical data, but worst of all, also from "internet facts" and rumors that may or may not reflect reality :)

I really appreciate what you are doing, and do not want to discourage you!

Absolutely phenomenal work going on in here... kudos guys!

Nyet,

Please don't worry. I took the S4 wiki to be what you intended it to be, a useful, basic guide to which tuning parameters to look at on an Audi S4. In research and in a work context, I've assessed and written enough technical documents in my time to know what's solid and what should be taken with a pinch of salt.

I upped the Draft to rev 3, removed references to the previous forum I was associated with and added a table of Tony's Stage 3 tune maps but that's all for now. I sent Tony a PM to see how much progress he had made in assessing it but he's clearly busy working on his excellent software.

If we hang on in there, in a few weeks or months, we should be able to pull together a good ME7.x Tuning 'How To'. A professional/commercial tune would be nice to get hold of but I'm not sure I'm brazen enough to try to read mine!

TTQS

Awesome info for the noobs like me thanks !

I promise to get back to work on reviewing the tuning document now. My bad for slacking off and focusing on my day job. >:(

I've just had a minor league brainwave...

I used the 240 PS variant of the VAG 1.8T engine as my benchmark only because I have that in my car. Although I had a Stage 2 commercial tune on it, I couldn't read it but because the 240 PS engine is a tuned version of the 225 PS engine I used those as the 'case study' if you like.

However, it just dawned on me that the venerable VAG 1.8T makes a great example for a case study, not necessarily just because an aftermarket tune can be so successfully applied, but because there a quite a number of stock tune levels.

For example, the TT alone had 150, 180, 190, 225 and 240 PS variants, so why not compare and contrast the key maps down the power scale? Surely this would be as useful as comparing the two higher power variants with a commercial tune of 265 PS...?

Back to the drawing board!

TTQS

Very helpful document my friend although i am a completely noob i manage to understand by your guide many many thinks about how the me7.5 works and how it can be tuned. Awesome

Hi all.

Tony has kindly reviewed my 'tuning guide' document up to LAMFA. I am busy at the moment but will incorporate his comments and revise it in the next few weeks. His comments are mainly corrections rather than supplementary information, so the fundamentals won't change. However, I will change it from Draft 3 to Revision 0 so it becomes a formal issue.

I have to admit that I was made aware of Greg Banish's excellent book "Engine Management: Advanced Tuning" only relatively recently and I wish I had read it before embarking on trying to write a guide to Motronic ME 7.x tuning! I'm currently at the end of Chapter 6 "The Recipe" where cylinder wall wetting (covered in the funktionsrahmen module ESUK 9.70) is discussed. I realise now that he covers the underlying fundamental principles very well indeed, particularly with respect to ignition angle influence on peak cylinder pressure and thus BMET.

However, another fundamental that is very well covered are the subtleties of tuning for larger flow rate fuel injectors. My document at Draft 3 only refers to KRKTE but voltage compensation curves and the short pulse width phenomena need to be discussed.

Regards.

TTQS

cant wait for Tony to get going on the "How to guide" and Doug i printed out your article and will be reading it tonight. Im a total noob when it comes to software all around. I am a VW tech and have the hardware down all the way. just wanted to branch off to hopefully get it all down.

Im also new to the whole Euro tuning in general. used to be a Honda guy :o i know  ::)

I'm hoping to have the revised issue up next week. I've just translated the RKTI funktionsrahmen module into a shape I'm happy with. I was going to then trace out the various line diagrams and incorporate these an an Appendix 4 but that might take some time because of their complexity so I might just paste the JPEG images in this time round.

TTQS

Only a few pages into this, and I'm already loving it. I'm a total noob, so a resource like this is invaluable. Great work!

TTQS, Thanks for taking the time to summarise and highlight the important calibration parameters for tuning a Audi TT fitted with a Bosch ME7 controller.

I read all 53 pages of your work.

Thank must have taken considerable effort!
I will reread it again as I may have some questions on certain calibratables.

Thanks for this work again.

Understanding ECU Remapping The Audi TT 1.8T Variants - Bosch Motronic ME7.x (Rev 1).pdf (18th September 2011, 1.06 Mb) now available. Word document format discontinued after feedback from nyet. See this post:
http://nefariousmotorsports.com/forum/index.php/topic,62.msg3330.html#msg3330

Translated funktionsrahmen modules
Any funktionsrahmen modules I have translated manually are on the Nefmoto wiki and on this stickied thread:
http://nefariousmotorsports.com/forum/index.php/topic,555.0title,.html

TTQS

awesome thank you very much for sharing it with us. The first one was great can't wait to read the new one. :D

Thanks Giannis. Much appreciated.

Hopefully, the changes are relatively subtle, just corrections, clarifications and bolstering some of the technical content. Like nyet, I'm paranoid about promulgating half-truths or opinions as hard fact.

I suppose if there were major issues, somebody would have shouted by now...

TTQS

TTQS

This is exceptional work and from someone who has been tuning since the early 90's hats off to what appears to be a lot of research and hard work. I did see a few things I would think are a bit different from my point of view but I will refrain because the overall picture is well done.

BTW, since I switched careers I work in the business of steam and here in the US, SIL studies are performed which is what I assume is similar to your background. he he... Just red to run, not green.....

Thanks rayce.

I presume you've been on the TT Forum and seen that I'm an Operations Engineer in the nuclear power sector? ;-)

http://www.tt-forum.co.uk/forum/viewtopic.php?f=29&t=196923

Regards.

TTQS

May i add something to the post? The map KFLF is not lambda at partial load but it works as a correction map added to the overal injection time. And it works opposite than lamfa.(kflf>1 add fuel, kflf<1 less fuel).

Which of the items 1. to 7. are by now covered?
If covered, where can info be found (link)?

Actually I read this entire post and you referred to your job in regard to your experience with writing technical articles which is far from my capabilities. Dyslexia robs me of the ability to get my point across in an easy to understand manner.

By background is Mechanic, Pro Sport Bike Tuner/Racer (1 National Win and tons of top ten finishes), Drag Race Junkie w old school Type 1 air cooled VW 550HP, now I am a Controls Engineer for Industrial Boilers.
(Closest to nuclear for us is aircraft carrier for Northrop Grumman, and Midland Cogeneration, Midland MI).

I hold a lot of certifications with computers and proceeded to move in to a better job when my airline career took a hit from Sept 11.




vtraudt,

Sorry,
We are getting off topic but pardon the pun stay tuned. I’d be glad to give my .02 about performance theory, porting, tuning and what the engine really needs to prevent damage and add horsepower.


FWIW
Since my mind goes all over the place, I wanted to comment that I am really suspicious that these chips are not programmed by the same manner that we are tuning. I really think that the software is a derivative of Siemens Step7 software and it is most likely written in function block. This would explain so many different comparisons and would make sense. How can a company keep track of so many different programs and for that matter follow the code if a change needs to be made.

Okay
The coffee is kicking in…I better go work on my car.

I have made some slight changes in response to Giannis point about KFLF:

"Although professional tuners do appear to adjust KFLF, it is part of the basic fuel injection module ESGRU 23.30 Grundeinspritzungen. This states that the map KFLF should not be used for mixture intervention because the map KFPU (which compensates for MAF sensor pulsations and signal interruptions) aligns the relative cylinder charge (rl) for the engine’s requirements. The S4 wiki notes that these tables are not very useful for fine tuning high load fuelling."

It seems reasonably clear when you look at the flow diagram in ESGRU 23.30 what KFLF is for. Teillast does translate as part load, but it's a basic map for lambda to which some factors are applied as deemed necessary by the OEM calibrator it seems.

TTQS

Thank you Doug i found this about kflf the last few days when i was trying to calibrate my car to go lean burn and it was going richer (i was setting it @1.10). I agree with you that in high rpm and load does not make big difference. I did't have time to read the new guide. I just would like to share my found with you. Regards.

Just curious, what are you doing to keep your oxygen sensor from trimming out your adjustments?

I am dissabling closed loop control for rpm that i want to run leaner. Search the forum. Sorry for off topic.

Document revised. Changes as below:

All. Minor editorial amendments, including standardizing the translation of 'soll' to 'target' instead of 'requested' or 'desired'. Correction of 'indicated' to 'indexed'.
Section 3.1 Interpretation of torque pathway from pedal angle to throttle angle in terms of maps and variables added.
Section 4. Reference made to manually translated funktionsrahmen modules available on Nefmoto.
New section 4.1 added to discuss the nature and origin of DAMOS & ASAP2 files. Existing sections renumbered.
Section 5.3.2. Remarks added for both KFMIRL and KFMIOP to note that (a) these maps are the inverse (complementary, not arithmetic inverse) of each other and changes made to one should be reflected in the other to avoid problematic operation (b) KFMIRL should be adjusted to tune part-throttle torque response.
Section 5.3.2. Section on LDRXN revised to compare and contrast with LDRXNZK.
Section 7.2. (Motronic German Terms and their Abbreviated Forms) amended

TTQS

Cool, and its a good read. Are any of the .ols files posted wideband?

Question: should I do the same in my map packs and s4wiki?

We're also (kinda) hampered by ECUx historical nomenclature...

As far as i can tell, given the ages of the cars they're from, they all are.

ME7.1 2.7ts are all narrow band.

Sorry, i meant the three .ols files attached to this thread by TTQS were all wideband.

All TTs have wideband HEGO sensors, I understand.

Personally, I don't think it's that important what language is used anywhere, that was just a minor edit to retain consistency. I think everyone knows what is meant. At work we tend to use MV and DV when referring to control loop behaviour on the plant, but 'target' seemed to be more used throughout ME7.x documentation and discussion.

TTQS

I started trying to compile what things needed to be modified and relevant information in a spreadsheet. I don't know 10% of what this forum knows so I was hoping we could all contribute to it and make it a impromptu step by step guide.

Its in a SUPER ALPHA state:

https://docs.google.com/spreadsheet/ccc?key=0ArJc7f8XNkGBdEZNZ05HV25CREJVMGpmQTF4aEgzNGc&hl=en_US

Great idea! If I have time i'll try to add in things from the s4wiki.

I'm not clear what value this is adding over and above the S4 wiki, the guide I wrote, the threads on this forum, etc. Sorry.

If you can write a step-by-step guide on tuning Bosch Motronic ME7.x, I suggest you contact the following publishers who produce Greg Banish's books. You could make good money out of it.  ;)

CarTech, Inc.
39966 Grand Avenue
North Branch, MN 55056 USA

I also recall nyet criticising my document on the basis that it's not in a wiki, not indexed, etc. therefore I'm surprised he thinks this venture is a good idea. Good luck with it all the same.

TTQS

the point is consolidation of information, the wiki is great but it doesn't group ideas and whats associated with them.

Your document while great is way to bulky to use as a cliff-notes. The goal here was to consolidate what maps do what with a brief description. Then at that point the user could reference things like your DOC or the WIKI or the FM for greater detail on the specified function of each map.

My hope was that anyone could look at this and say hey I want to add a larger throttle body how do I do that? Ok here are the maps associated with doing said activities, now go research.

As he said, what appealed to me was the concept of a quick reference for "I have problem x, where should I start"..

Also, I like google docs because it is collaborative.

I love the idea that ejg3855 posted. I have my own "cliff notes" so to speak, but it would be great to get a compiled data sheet based on an input from everybody. I switch back and forth between TTQS guide, and Nyets wiki a lot, but every little bit helps. Why not?
 

Thanks for the agreement, I have been uber busy at work and haven't had time to collaborate much on the document.

There isn't any reason the wiki couldn't be used for this...

Entirely correct, except the wiki isn't a collaboration everyone can't work on it.

And how can I edit that file over at google docs (almost all buttons are grayed out)? I thought that everyone can add their own ideas and suggestions for specific problems...

There isn't any reason A wiki couldn't be used for this..

Can anyone edit wiki?

I should probably clarify my position on wikis... I'm not anti wikis so long as all the potential users and collaborators are agreed on what should be in it and the mission statement is clear.

While nyet conceived the S4 wiki from the start as a body of knowledge that others could add to, change and correct, I didn't write my guide as a "how to" as such and I didn't conceive it as a document that other tuners could hack about and contribute to.

I have a track record of producing technical documents which are (intended to be) factually correct, 'absolute' and are peer-reviewed to verify the facts, reduce or ideally eliminate errors so I just stuck with a format that I was comfortable with, but for sure, it didn't really address the spirit and intent of the original post of a genuine 'how to'.

Therefore, there is still 'a gap in the market' whereby Nefmoto users would identify specific goals of interest tuners of VAG Motronic ME7.x ECUs and then write up the salient points (or, better still) produce flow diagrams with annotations to summarise such.

I'll happily contribute to such a thing if I can, just as I have felt able to do with the FR translations. I would just like to see some agreement and identification of specific matters up front then people getting on and producing quality outputs. There's too much tat, rumour and sigh out there on the internet at large but I do like to think that Nefmoto has risen above all that.

... there's a good illustration of how to say nothing much in many words! ;)

TTQS

Agreed. And if we will use wiki then please make it so that everyone registered could edit it and add useful information. You know wikipedia? It's that big because EVERYONE contributes ant not only selected people ;) Just a suggestion

Anyone *can* edit the wiki. Just re-register. Or have I missed the point?

Great read. I read a DIY long ago at another forum for the m7.5 but can no longer find it. I always come back to wanting to selftune my awp 1.8t but since last winter when i was searching for data and all i could find was the s4 wiki, this forum takes leaps ahead of what I could learn before. Although I don't know much now I hope I can lean and help at somepoint.

from Doug's pdf:


question:

at a given lambda, does flame speed change if I change the charge (boost)?

simple question, but I think the answer is not.

Of course it does, flame speed is dependant on charge density (boost)...

any physical evidence?

I just did a quick web search for factors affecting flame propagation rate in internal combustion engines (a commonly covered topic) and Google Books threw up "Internal Combustion Engines" by V. Ganesan. I paraphrase the section on this:

For efficient combustion, the rate of propagation of the flame front is critical. The two important factors which determine the rate of movement are the chemical reaction rate and the transposition rate (i.e. the physical movement of the mixture).

Several factors affect flame speed. Turbulence (increases the reaction probability by better mixing of burned and unburned mixture). Excessive tubulence may extinguish the flame and AFR (large influence) seem to be the most significant.

As for temperature and pressure: flame speed increases with an increase in intake temperature and pressure. Molecules are closer together at higher charge density and moving about more at higher temperature which will both increase the chemical reaction rate. IMO, this should far outweigh any reduction in transposition rate due to the denser, heavier charge.

TTQS

Thanks, that sums it up.

But looking at any SI engine's ECU structure should have given it away.
Axes on the main ignition maps (not talking about correction maps) are always RPM and some representation of load. (throttle angle, MAP, direct airmass, abstract load, whatever...)
You can always somehow relate these measurements back to charge/cyl. filling.
Why would such systems use load as a main lookup factor when it wouldn't affect flame speed? :-)

@TTQS
Sorry, but that isn´t correct. The european APX Engine (225PS - predecessor of the BAM engine) is non wideband. It has only one narrowband hego pre cat. ECU Number is 8N0906018AE or 8L0906018M.

A big "Thank you" for developing the "Understanding ECU Remapping".pdf -> This will be the literature for tonight and i can´t wait to read it  :-)
I still wonder why i did not found this thread earlier? That was right the stuff i was looking for all the time. I´m more into (engine) hardware than in software stuff but still very interested in learning the Me7.5
Without a good software the best hardware is a waste of money ;-)

O.k., no problem. Good spot for pointing out the correction and thanks for the appreciation. You obviously know your TT specs. I hope you don't fall into the trap that I've seen other Mk1 TT enthusiasts succumb to which is to just bolt on hardware upgrades without understanding the overall effect on the ECU calculations.

I see the agent that did my Revo remap has switched back to APR after less than 18 months with Revo.  ::)

TTQS

That´s why i´m here.  ;)
I´d like to understand the ECU calculations BEFORE i upgrade my hardware!
I don´t like to give the car away to a"tuner" to get a remap not knowing what he changed within the maps nor to get satisfieng answers what he has done.
Thanks for providing the BAM/BFV files, helping to understand the differences a lot.

very true, but it underlines what I mean: there is no simple "factor" to calculate the flame speed depending on boost. you need to determine it on experience or dyno.


yes, I would like to have that proved ;)  "IMO" and "should" is no physical law. and indeed it seems to neutralize each other. many tunes (not only me7) work fine by increasing boost and changing lambda significantly, but not touching ignition.

I have few small questions:
during part throttle ecu ignores LDRXN and works only in KFMIRL limits?
during wot ecu ignores KFMIRL limits and works only in LDRXN limits?

or LDRXN is applied no matter what,  but during wot kfmirl is ignored?

Of course. If it would be possible to calculate optimum ignition angles in real time with a few given measurements, then ECU developers would have integrated an algo for that a long time ago. Instead even recent systems use dozens of tables, which need to be applicated by the calibration engineer.
I'm pretty sure you can model engine physics well enough to get useable ignition angles from a model, but that needs serious computing power and elaborate calculations.
Way beyond any feasible DIY approach and that is why all calculators and interpolation/extrapolation approaches to calculate stuff "easily" are useless.


Yes, those tunes work "somehow". The word fine does not belong anywhere near that sentence ;-)
The reason is simple, an SI engines works "somehow" with a rather broad variance in operating parameters. But making stuff optimal is a whole different game.

I somehow miss the old days when ECUs didn't have these clever knock and component protection schemes, that would have made a lot of tuners much more humble.
The trail of detonated engines would have put their crap out of busines much sooner!

A quick Google search again reveals that the thermodynamics and flame front velocity in internal combustion engines can be modelled.

Have a look at the attached PDF file:

"MODELING OF TURBULENT FLAME VELOCITY FOR SPARK IGNITION ENGINES"

The following site has Java applets for calculating various ICE thermodynamic parameters. I didn't see flame speed in there, but you could have a play.

http://www.engr.colostate.edu/~allan/thermo/page1/page1f.html

Also, the physics of an automotive engine with a section on flame speed propagation is covered here:

http://mb-soft.com/public2/engine.html

A couple of equations for calculating the flame front velocity are presented. These show that higher temperatures and pressures increase the flame speed.

That's the best I can do in 10 minutes on Google. Hope this helps.

TTQS

Wat??

rlmx_w is output from LDRXN based on RPM, it is then limited for different conditions and output as rlmax_w.

The output from KFMIRL is capped by rlmax_w.

As a result, specified load rlsol_w is calculated from KFMIRL but cannot exceed rlmax_w.

See %LDRLMX and %MDFUE in the FR.

Doug,
thanks for the .pdf that seems very close to what I was asking.

the initial pressure mostly seems to be in the numerator part of the equation but the further modeling and experiments show different results.

So my understanding is: flame speed is not equivalent to pressure in any linear or simple non linear form and need to be calculated or applicated by experiments in a way more complex way.


(the other site did not convince me to be very scientific and does some assumptions I don't know. and not only because it also hosts sort of this: http://mb-soft.com/public3/911scien.html)

Oh dear!  :o

TTQS

great job!
Why don't you add an appendix on the launch control? : D

Unfortunately, the document is entirely uneditable, and, as i predicted, became abandonware.

.doc is an utterly useless format, from an information sharing and cooperative effort perspective.

I don't understand. If you could have this PDF as a .docx so the content can be edited. You wouldn't be interested?

There is no good way of collaboratively editing the doc format.

no change history, no merge, no revision control, no rollback

I see your point.
 What would be the ideal format in your opinion?

wiki or docbook

or, alternatively, a single active curator/author that keeps the document constantly up to date..

Careful - NOOB at work :D

This is a great document - THANKS.

I am right at the very beginning of the learning curve on tuning this! I have read the document a few times now - its a lot to take in, but learning all the time....

I have seen that some guys here have reverse engineered the code running the ECU, even adding map switching to the code etc.

With this in mind, I was thinking of something that would add great value to this document/forum to help people understand the ecu and tuning it. It would be awesome to have a given set of inputs - eg Throttle position, engine temp, intake temp etc etc - then have a flow diagram/list of exactly what the ecu does (in what order, calculations, map look ups etc ) with this to arrive at given outputs like injection timing, injection pulse time, throttle plate angle, boost, ignition angle.

So on a given ecu, we could follow step by step through the code, see what it does, where it gets info from in the map/eprom. Actually see the values returned and see how they are used to get actual values that will then be used for the motor.

This is probably a massive undertaking - probably bigger than I imagine!! But it would really be great. This is exactly the understanding I would love to have eventually - my thinking is if you can do this you will really know what you are doing!

Don't flame me too bad - I'm a NOOB ::)

Maybe I am nuts but could be possible that we can modify OEM & Tuned software in our ECUs to a much powerful level like DSM people have done with Evo ECUs???? Something like this:
http://forums.evolutionm.net/ecuflash/451836-tephramod-v7.html
http://forums.evolutionm.net/ecuflash/497325-tephraxmod-v1.html
http://geekmapped.com/forums/showthread.php?t=1945

Check out philas map switching routine. It uses the CEL as a knock light, Cruise control map switching, etc, etc.

The document became abandonware because I stopped frequenting this forum and therefore lost the desire to update it, sorry.

My 1999 PhD thesis is also entirely uneditable and therefore abandonware. It is also a standalone piece of work, as this basic "getting you started" guide was meant to be. ;) Why would somebody want to edit information that was in some cases derived from logging on my own car?

Don't forget that I contributed all my translated modules to the wiki as well as abandonware versions. As I have explained before, if I wanted to create a wiki, I could have done so, but you had already created the S4 wiki which did the job.

I would happily have maintained an ongoing interest, but since I stopped coming here regularly, I have had two children. Also, I was promised by another member a look at the code from a household name commercial big turbo tune. The guy himself was busy with his job and family so it never materialised. That would have helped me contribute and revise the document to gain some more insights.

Sorry I couldn't maintain an active presence.

TTQS

TTQS

Welcome back sir... It's been too long...