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1.8T M3.8.3 tuning

Thomas_20VT Dec 19, 2017

  1. Stuart B

    Stuart B Well-Known Member

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    The only reason I asked - is you only joined ASN yesterday a day after Thomas's thread, although I "lurked" on these forums for a while awaiting some inspiration too.

    I certainly am no expert in the ECUs but my little understanding is ME7.5 controls the components to achieve the "numbers requested" and M3.8 reacts to the values from components to try and work out what the numbers are - making any meaningful hobby modifications an "expensive" <-- not in money but time and fruitless (dangerous) experimentation.

    When I had my 2003 Kia Sedona I bought essentially a variable resistor which turned the diesel pressure up and that made a V6 3.0 CRDi 15% more powerful than before? but the other day I told my ME7.5 I wanted a maximum of "210" (whatever's) @ 5500RPM @ 100% load which equals about 21PSI and said I want the car to try and get 0.83 Lamda - and that is after a couple of hours of reading? 3 additional settings later I have set a 2 step launch control, I was told don't touch a PID as I will not know what to set properly - this is why people are not fans of "difficult" / "black art" tuning.
     
  2. mogsalie0010

    mogsalie0010 New Member

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    So we on the same page.,,im too very green when it comes to tuning ecu,, eventhou I would love to know how my ecu works and understand how to tune my ecu(m3.8) and other ecu if needs be,, I dont mind the hours struggling,, but getting it right at the end of the day,,that feeling of accomplishment is priceless,,

    Sent from my HUAWEI CRR-L09 using Tapatalk
     
  3. mogsalie0010

    mogsalie0010 New Member

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    I bought a mpps v16 software and cable to try and read and write and familiarize myself with my car ecu but was unable to read I then heard that the kwp 2000 plus tool will work om my car and I wasted no time and went to purchase it,, but yet I wasnt able to even read my ecu.,,,lol

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  4. Broken Byzan

    Broken Byzan Photographic Moderator Staff Member Moderator VCDS Map User quattro Audi A4

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    m383 cannot be read over obd, only flashed.
     
  5. Stuart B

    Stuart B Well-Known Member

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    don't you need to "fake the k-line" using the extra hard wire - Prawn raised earlier? even the AMK S3 Me7.5 has problems with using ME7Logger because of the connectivity.

    "cars are s h i t e"
     
  6. antwan64og

    antwan64og Active Member

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    The eprom can only be read if you desolder it and read it with something like monoscan, but you don’t need to do that.

    Other people before you have done it and the files are available. Some ecu flashes end 018R, 018AQ etc. Just so add to the confusion for each ecu although the numbers match there appear to be variations and not all match up on a definition file even if it was made for the same ecu number.

    When it gets warmer I hope to be able to test more things on the car and release a basic tuning guide for the ecu on nefarious, with a stock bin and fairly comprehensive xdf explaining how the maps interact.

    The main holdup is the two key constants KFHM and FGATO are not fully understood and they cannot be worked out mathematically. What people do effectively is trial and error; put in new injectors and reduce FGATO until it idles ok, adjusting TEMIN (min injection), TLST (start fuel ms), TVUB (injector voltage correction) then massage the KHFM figure until it keeps max load below 12.75ms (theoretical max load threshold). Which is a BS nightmare to tune before you even get to the actual tuning, the correction tables and cold/hot start.

    Yes you can have baseline numbers for 310cc Yellows, 415cc Genesis, 440cc Bosch but that only gets you in the ballpark. The ecu depends on the hardware and everyone has a different configuration of parts once they start modifying so will always need tweaking.

    Ideally you’d need a 29F200/28F200 emulator and byte swap board for real time tuning but at the cheapest end that’s a $500 investment.

    Rtech used to take a week to custom tune the cars and he worked with the ecu a lot, had a dyno and an emulator.

    Sounds like a fun ecu to tune doesn’t it Bill....
     
  7. Stuart B

    Stuart B Well-Known Member

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    it sounds like a £2000 invoice to map a £700 car?

    how much is a K6 emerald? -- or whatever Prawn uses!
     
    jimmcgee likes this.
  8. antwan64og

    antwan64og Active Member

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    Its £25 if you source a cable checksum plugin.
    Then a £130 for a wideband.
    Then hours of your life hoping to find the holy grail that Bosch motronic logic will one day make sense, lol.
    For example Max load threshold is 12.75ms in the LDR boost maps, but max injection shown in VCDS is 16.32ms (presumably due to sampling rate), you have to calculate duty cycle above that point.
    WTF!

    You can get it running ok(ish) quite quickly, to get it perfect is what takes the time.

    After a quick look it looks like Max air flow you can put in the MAF table is 7991.89 Kg/hr of air flow (according to the graph, I didn’t check what 255 equates to in the hex editor) which equates to approximately 2750 hp but the resolution would be awful, lol.

    Even If a smart guy put in the time to make a nice M3.8.3 tune for specific hardware like the K380 kit, 3.5” downpipe to 3” exhaust with Wellycooler, N/A cams, etc I doubt they would freely share their knowledge afterwards as they lost hours of their life doing so and it would need tweaking as soon as someone went overbore due to scores in cylinders.

    So this is why no one ever really bothered with the ecu
     
    SHUk and badger5 like this.
  9. SHUk

    SHUk Once Bitten Forever Smitten =]

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    All your input is greatly received...

    Thank you!
     
  10. mogsalie0010

    mogsalie0010 New Member

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    Isnt that supose to reason enough for some1to actually get to know that ecu,,I would actually love to get to know that ecu and what makes it work,,,

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  11. jimmcgee

    jimmcgee Active Member

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    :readit: I love posts like this , excellent info all round :cheerful:
     
  12. badger5

    badger5 www.badger5.co.uk Site Sponsor

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    full of primdonna ********* more like..
    all you need to know there is read the fcuking function diagram. Thats all they will tell you 99% of the time. A "few" helpful soles in there but dayum otherwise, its a vipers nest.. each wanting to "out smart" the other in knowledge etc... Sadly..
     
    Last edited: Dec 21, 2017
    jimmcgee likes this.
  13. mogsalie0010

    mogsalie0010 New Member

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    What would you guys recommend,, diktator 60-2 stand alone ecu or having ecu(agu) remapped.

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  14. badger5

    badger5 www.badger5.co.uk Site Sponsor

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    what this non linear "linear thing"
    [​IMG]
     
  15. badger5

    badger5 www.badger5.co.uk Site Sponsor

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    MLHFM in M3.8?
     
  16. badger5

    badger5 www.badger5.co.uk Site Sponsor

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    I know.. lol
    but you posted up a list of map names... MLHFM one of them, in the context of M3.8?
     
  17. badger5

    badger5 www.badger5.co.uk Site Sponsor

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    yea but no.. lol
    but I do have an ols300 emulator and an m3.8 ecu with headers soldered onto it.. but never got round (/could be bothered) to play mroe with them, when I can better serve the wide range of turbo/engine/ builds by stand alone ecus and their respective pnp adaotors.
    They interest me but only up to the point of way too busy to actually "get into them" as it were.
     
  18. Thomas_20VT

    Thomas_20VT New Member

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    I do know NefMoto forum but they are ME7 or newer addicts and I don't like the atmosphere that much to be honest... even if there are people who do really know what they are talking about !

    BOOST regulation and monitoring

    Boost is controlled using MAF signal and N75 valve. It is a PID-regulator using a pre-control map KFLDTV. This one has 2 axis which are throttle angle and engine speed. The values given are % of PWM duty cycle that controls the N75 valve

    N75_map.png

    I will not into too much details as it might not be so relevant for tuning unless going mental. For the regulation, there are additional curves for Gain (P-part), Integrator (I-part) and Derivative (D-part) with windows for fast or slow regulation and so on...

    For people not willing to spend a lot of time on doing the things right and like the italian tuning, you could use only waste-gate duty cycle to control boost by setting all the PID parameters to '0' :disappointed:

    For monitoring purposes and avoiding that you either kill your engine or break your turbocharger in case for example the pipe on the waste-gate would have fallen down and give maximum boost with no opening of the waste-gate. There is a map (KFMLDMX) defining the max load that can be expected without a defect in your turbocharger regulation system. When MAF sees values greater that what is in this MAP, it will go into limp-mode.
    Axis are throttle angle and engine speed with values filled in the map being airflow in kg/hr => at 6000rpm, 704kg/hr is roughly 1,0-1,1bar

    MAX_load_diagnosis.png

    Badger5, there IS a MLHFM curve in M3.8, same as in ME7
     
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  19. antwan64og

    antwan64og Active Member

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    Difference is you probably have the official super mappack ols or kp file for the ecu so if they call it something different in there I don’t know.

    I just have what was gleamed/cross referenced from the M3.8.2 Ols and the various xdf and ols from diy enthusiasts and everyone uses MLHFM to describe the MAF table 0-4.98v. Previously it was well known rescaling the MAF kicks in other limiters so its left and the ecu keeps timing and fuel the same as the last cell even though it’s off the map. So with a 2.75” VR6 MAF saturating at 320hp with VCDS Reading 187G/s you could run nicely upto 400hp even though the ecu was blind and unscaled.

    Some of the ECU Files I have from a DIY tuner in Austria has successfully rescaled MLHFM, I haven’t trawled through the files and compared the threshold limits he had to change to make it work though.
     
  20. badger5

    badger5 www.badger5.co.uk Site Sponsor

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    interesting stuff
     
  21. Broken Byzan

    Broken Byzan Photographic Moderator Staff Member Moderator VCDS Map User quattro Audi A4

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    This was what i was trying to say, however badly
     
  22. antwan64og

    antwan64og Active Member

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    I missed a key point reading back and just wanted to clear it up.


    If you leave MLHFM as stock with a max reading of 673 Kg/hr, you can add bigger injectors, adjust FGATO, TEMIN, TLST, TVUB and get it running to map it.

    Then using a bigger MAF housing in proportion to injectors means the load has shifted and the timing especially will really need lowering for everything above 2000rpm but fuelling should be close. The MAF readings will max out at 187 G/S and not be an accurate reading.


    If you change MLHFM so that the MAF reads correctly to say 915 Kg/hr (253 G/S), then the Load (Ld) measured in ms will exceed 12.75ms (the maximum).


    Load calculated as

    Ld = K * (MLHFM/KHFM)


    To effectively keep the load below 12.75ms when you raise MLHFM to be accurate; you need to change KHFM. KHFM is effectively a load constant (here’s the kicker) which means that a change here means every map using load needs rewriting.


    So choose to unscale the MAF and have some work to do or scale the MAF and have a hell of a lot of work to do.
     
  23. Thomas_20VT

    Thomas_20VT New Member

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    What is easier when you hit 12,75ms load limit is to multiply KHFM by a factor so that load remains with numbers around 10ms and scale FGATO with the same factor so that fueling MAPs are 95% right and you take care of timing MAPs with some logging comparison before and after this mod and checking timing pull at the same time


    I don’t even mention KLHFM as I don’t see the point in mis-calibrating this parameter
     
  24. mogsalie0010

    mogsalie0010 New Member

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    Hi guys.,,, im in search of a second opinion.,, I rebuilt my golf 4 20vt engine replaced rings,bearings etc and new turbo even, and had my cylinder head by engineers,for valve stem seals and reseating of my valves. Now all of a sudden when I wanted to start my car today I have got no compression on cylinder 2,3 and 4..,? Any suggestions.,,?

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  25. Stuart B

    Stuart B Well-Known Member

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    You should start your own thread really. This thread is about mapping A3 150/180 ECUs
     
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  26. mogsalie0010

    mogsalie0010 New Member

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    My bad.,,, sorry abt that

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  27. Stuart B

    Stuart B Well-Known Member

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    Forum experts in these engines will be able to advise you properly in your own thread.
     
  28. mogsalie0010

    mogsalie0010 New Member

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    Thanks

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  29. Thomas_20VT

    Thomas_20VT New Member

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    Happy new year to all !

    Chapter: LOAD calculation


    As there seem to be one main fear about M3.8 leading to people saying that this ECU is sh*t and should be replaced by either standalone ECU (which can't do half of what a stock ECU does!) or switch to ME7.5 (way better than M3.8 but require money and electrical skills)

    I decided to investigate a bit with my stock AGU to figure out if there may be a way to tune those M3.8 ECUs for big HP figures.

    The main worry was the side effects caused by scaling load by KHFM as all the MAPs using load as an axis will be wrong and must be redone. This can be a very time consuming process and the reason why most people don't bother with this ECU

    Here is data from VCDS logs on my own car:
    Load_KHFM.png
    I am able to back-calculate theoretical Load purely from MAF (g/s) read by VAGCOM and using KHFM in the following formula:

    Load [ms] = (4/2) x 3,6 x MAF x KHFM /1000 / RPM

    where: 4/2 is the number of cylinders divided by the number of cylinders being ignited per revolution (4-stroke engine) and the other factors are only for unit conversion.

    How to proceed from here:

    First, scale your KHFM factor (43860 as stock value) so that you keep load in a safe area with enough marging against the 12,75ms hard limit.
    Then, you scale FGATO (injector constant) by the same factor as you used for KHFM so that all the injection maps using load will still be correct.

    The work you need to make on your own is then for timing advance where you should recalculate your load axis supporting points so that they match with the scale you made on KHFM.

    This way, all should be functional at once and require only slight fine-tuning but as you would do anyway with any kind of ECU.

    (on the graph, load calculation error range is very narrow between -0,7% to 0,9%. Considering there is already a 0,7% error only from VCDS accuracy at 7ms with only 0,05ms steps, I think that this formula is the right one)

    Any opinion ? or data from some other vehicles ?

    Next time, I will try to have a better understanding of fueling strategies as there are still some few parameters which I need to figure out first
     
  30. antwan64og

    antwan64og Active Member

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    Someone was using 1300cc injectors on nefarious with E85. I didn’t ever see that it was running nicely though.

    You can rescale the load axis if desired, one configuration I have has 12ms instead of 10ms, some resolution is lost but it depends what you want.
     

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