Useful resources for getting started

From B58 Wiki

Background information

Modern engines for dummies

N54 and N55 Tuning

There are a lot of similarities but N54 tuning is simpler.

PID control

Dialling in boost control requires a familiarity with PID error control. If you are new to this, these introductions are highly recommended and enough to get you started.

Other B58 tuning resources

Tools for tuning

A2L file for your car

Having an A2L file that corresponds to your car is the resource for tuning because it describes every value, curve and map in the (stock) ECU. The A2L also describes all the units of these quantities and BMW's A2L are fairly well commented which helps with understanding.

As well as maps, the A2L describes every function and measurement in the ECU and the relationships they have to the maps. This provides a black-box view of what the ECU is doing and, although this does not describe the calculations taking place inside each function, for tuning purposes it is often enough to see the inputs and outputs.

It is worth remembering that, inside each function, the ECU only performs map lookups, simple arithmetic and logic operations. It is a real-time system so any complex calculations, and even square roots, are loaded into maps. This means the implementation is often somewhat guessable from inspection of the inputs and outputs, their units and BMW's comments.

By way of example, the graph below was generated from a gen 1 A2L (using tools at https://github.com/jtownson/xdfbinext) and shows the ECU considering pressure across the cat. From this and graphs like it, one can often work out which maps need inspecting and changing.

Finding the A2L for you car

Inside A2L there is an identifier called the EPK. This is hardcoded inside the A2L and, in addition, there is an EPK_ADDR property which provides a memory location for the EPK in calibration data files. This allows people and software tools to match up EPKs in an A2L and a bin.

Here is an example:

 /begin MOD_PAR "MG1CS003"
   VERSION "R1C2J8B3B"
   ADDR_EPK 0x96C5AE8
   EPK "53/1/MG1CS003/11/MG1CS003_BX8_R1C2J8B3B//R1C2J8B3B///"
   ...

A technical issue is that if we start with a (stock) bin taken from a car, we do not know the EPK_ADDR. Nonetheless we can use a command like the linux strings command to scan the bin and find the EPK string. Alternatively tools like WinOLS will search for and find it (including the demo version).

   $ strings 00003076501103_original.bin | grep MG1CS003
   #DME__861#D1#BTL#MDG1G_LK-CB_011_253.5_1.A#MG1CS003_LK______________________________________________________________________________________________________________________________________________________________
   53/1/MG1CS003/11/MG1CS003_BX8_R1C2J8B3B//R1C2J8B3B///
   53/1/MG1CS003/11/MG1CS003_BX8_R1C2J8B3B//R1C2J8B3B///

Clearly this bin corresponds to A2L version R1C2J8B3B.

By running this query for all bins in the BMW-XDF repo provides the following:

Original bin vs A2L correspondence
Gen Bin File A2L Version Full EPK
Gen1 00003076501103_original.bin R1C2J8B3B 53/1/MG1CS003/11/MG1CS003_BX8_R1C2J8B3B//R1C2J8B3B///
Gen1 00003076501D02_original.bin R1C2J8I2B 53/1/MG1CS003/11/MG1CS003_BX8_R1C2J8I2B//R1C2J8I2B///
Gen1 000030765A3C06_original.bin R1C2JD06B 53/1/MG1CS003/11/MG1CS003_BX8_R1C2JD06B//R1C2JD06B///
Gen1 00003081501102_original.bin R0C2J8B2B 53/1/MG1CS003/11/MG1CS003_BX8_R0C2J8B2B//R0C2J8B2B///
Gen1 00003081501D04_original.bin R0C2J8I4B 53/1/MG1CS003/11/MG1CS003_BX8_R0C2J8I4B//R0C2J8I4B///
Gen2 00005D55289606_original.bin R4C2F4E6B 56/1/MG1CS201/11/MG1CS201_BX8TUE_R4C2F4E6B//R4C2F4E6B///
Gen2 00005D5528AA06_original.bin R4C2F4K6B 56/1/MG1CS201/11/MG1CS201_BX8TUE_R4C2F4K6B//R4C2F4K6B///
Gen2 00005D5528B405_original.bin R4C2F4N5B 56/1/MG1CS201/11/MG1CS201_BX8TUE_R4C2F4N5B//R4C2F4N5B///
Gen2 00005D5528BE07_original.bin R4C2F4P7B 56/1/MG1CS201/11/MG1CS201_BX8TUE_R4C2F4P7B//R4C2F4P7B///
Gen2 00005D5528BE09_original.bin R4C2F4P9B 56/1/MG1CS201/11/MG1CS201_BX8TUE_R4C2F4P9B//R4C2F4P9B///
Gen2 00005D55327806_original.bin R4C2H596B 56/1/MG1CS201/11/MG1CS201_BX8TUE_R4C2H596B//R4C2H596B///
Gen2 00005D55328C05_original.bin R4C2H5C5B 56/1/MG1CS201/11/MG1CS201_BX8TUE_R4C2H5C5B//R4C2H5C5B///
Gen2 00005D55329606_original.bin R4C2H5E6B 56/1/MG1CS201/11/MG1CS201_BX8TUE_R4C2H5E6B//R4C2H5E6B///
Gen2 00005D5532BE07_original.bin R4C2H5P7B 56/1/MG1CS201/11/MG1CS201_BX8TUE_R4C2H5P7B//R4C2H5P7B///
Gen2 00005D5532BE09_original.bin R4C2H5P9B 56/1/MG1CS201/11/MG1CS201_BX8TUE_R4C2H5P9B//R4C2H5P9B///
Gen2 00005D5532C808_original.bin R4C2H5S8B 56/1/MG1CS201/11/MG1CS201_BX8TUE_R4C2H5S8B//R4C2H5S8B///
Gen2 00005D5532DC05_original.bin R4C2H5V5B 56/1/MG1CS201/11/MG1CS201_BX8TUE_R4C2H5V5B//R4C2H5V5B///
Gen2 00005D553C6405_b58o1_original.bin R4C2H695B 56/1/MG1CS201/11/MG1CS201_BX8TUE_R4C2H695B//R4C2H695B///
Gen2 00005D553C6405_original.bin R4C2H695B 56/1/MG1CS201/11/MG1CS201_BX8TUE_R4C2H695B//R4C2H695B///
Gen2 00005D553C6E05_b58o1_original.bin R4C2H6B5B 56/1/MG1CS201/11/MG1CS201_BX8TUE_R4C2H6B5B//R4C2H6B5B///
Gen2 00005D553C6E05_original.bin R4C2H6B5B 56/1/MG1CS201/11/MG1CS201_BX8TUE_R4C2H6B5B//R4C2H6B5B///
Gen2 00005D553C7805_original.bin R4C2H6D5B 56/1/MG1CS201/11/MG1CS201_BX8TUE_R4C2H6D5B//R4C2H6D5B///
Gen2 00005D553C7807_b58o1_original.bin R4C2H6D7B 56/1/MG1CS201/11/MG1CS201_BX8TUE_R4C2H6D7B//R4C2H6D7B///
Gen2 00005D553C7807_original.bin R4C2H6D7B 56/1/MG1CS201/11/MG1CS201_BX8TUE_R4C2H6D7B//R4C2H6D7B///
Gen2 00005D553C8207_b58o1_original.bin R4C2H6H7B 56/1/MG1CS201/11/MG1CS201_BX8TUE_R4C2H6H7B//R4C2H6H7B///
Gen2 00005D553C8207_original.bin R4C2H6H7B 56/1/MG1CS201/11/MG1CS201_BX8TUE_R4C2H6H7B//R4C2H6H7B///
Gen2 00005D553C8C05_b58o1_original.bin R4C2H6K5B 56/1/MG1CS201/11/MG1CS201_BX8TUE_R4C2H6K5B//R4C2H6K5B///
Gen2 00005D553C8C05_original.bin R4C2H6K5B 56/1/MG1CS201/11/MG1CS201_BX8TUE_R4C2H6K5B//R4C2H6K5B///
Gen2 00005D553C9607_b58o1_original.bin R4C2H6N7B 56/1/MG1CS201/11/MG1CS201_BX8TUE_R4C2H6N7B//R4C2H6N7B///
Gen2 00005D553C9607_original.bin R4C2H6N7B 56/1/MG1CS201/11/MG1CS201_BX8TUE_R4C2H6N7B//R4C2H6N7B///
Gen2 00005D553CA007_b58o1_original.bin R4C2H6P7B 56/1/MG1CS201/11/MG1CS201_BX8TUE_R4C2H6P7B//R4C2H6P7B///
Gen2 00005D553CA007_original.bin R4C2H6P7B 56/1/MG1CS201/11/MG1CS201_BX8TUE_R4C2H6P7B//R4C2H6P7B///
Gen2 00005D553CA009_b58o1_original.bin R4C2H6P9B 56/1/MG1CS201/11/MG1CS201_BX8TUE_R4C2H6P9B//R4C2H6P9B///
Gen2 00005D553CA009_original.bin R4C2H6P9B 56/1/MG1CS201/11/MG1CS201_BX8TUE_R4C2H6P9B//R4C2H6P9B///
Gen2 00005D553CAA08_b58o1_original.bin R4C2H6S8B 56/1/MG1CS201/11/MG1CS201_BX8TUE_R4C2H6S8B//R4C2H6S8B///
Gen2 00005D553CAA08_original.bin R4C2H6S8B 56/1/MG1CS201/11/MG1CS201_BX8TUE_R4C2H6S8B//R4C2H6S8B///
Gen2 00005D553CBE05_b58o1_original.bin R4C2H6V5B 56/1/MG1CS201/11/MG1CS201_BX8TUE_R4C2H6V5B//R4C2H6V5B///
Gen2 00005D55461E08_b58o1_original.bin R4C2J718B 56/1/MG1CS201/11/MG1CS201_BX8TUE_R4C2J718B//R4C2J718B///
Gen2 00005D55461E08_original.bin R4C2J718B 56/1/MG1CS201/11/MG1CS201_BX8TUE_R4C2J718B//R4C2J718B///
Gen2 00005D55463208_b58o1_original.bin R4C2J758B 56/1/MG1CS201/11/MG1CS201_BX8TUE_R4C2J758B//R4C2J758B///
Gen2 00005D55463208_original.bin R4C2J758B 56/1/MG1CS201/11/MG1CS201_BX8TUE_R4C2J758B//R4C2J758B///
Gen2 00005D55463C07_b58o1_original.bin R4C2J797B 56/1/MG1CS201/11/MG1CS201_BX8TUE_R4C2J797B//R4C2J797B///
Gen2 00005D55463C07_original.bin R4C2J797B 56/1/MG1CS201/11/MG1CS201_BX8TUE_R4C2J797B//R4C2J797B///
Gen2 00005D55464605_b58o1_original.bin R4C2J7A5B 56/1/MG1CS201/11/MG1CS201_BX8TUE_R4C2J7A5B//R4C2J7A5B///
Gen2 00005D55464605_original.bin R4C2J7A5B 56/1/MG1CS201/11/MG1CS201_BX8TUE_R4C2J7A5B//R4C2J7A5B///
Gen2 00005D55465005_b58o1_original.bin R4C2J7N5B 56/1/MG1CS201/11/MG1CS201_BX8TUE_R4C2J7N5B//R4C2J7N5B///
Gen2 00005D55465005_original.bin R4C2J7N5B 56/1/MG1CS201/11/MG1CS201_BX8TUE_R4C2J7N5B//R4C2J7N5B///
Gen2 00005D55465A07_b58o1_original.bin R4C2J7P7B 56/1/MG1CS201/11/MG1CS201_BX8TUE_R4C2J7P7B//R4C2J7P7B///
Gen2 00005D55465A07_original.bin R4C2J7P7B 56/1/MG1CS201/11/MG1CS201_BX8TUE_R4C2J7P7B//R4C2J7P7B///
Gen2 00005D55465A09_b58o1_original.bin R4C2J7P9B 56/1/MG1CS201/11/MG1CS201_BX8TUE_R4C2J7P9B//R4C2J7P9B///
Gen2 00005D55465A09_original.bin R4C2J7P9B 56/1/MG1CS201/11/MG1CS201_BX8TUE_R4C2J7P9B//R4C2J7P9B///
Gen2 00005D55466408_b58o1_original.bin R4C2J7S8B 56/1/MG1CS201/11/MG1CS201_BX8TUE_R4C2J7S8B//R4C2J7S8B///
Gen2 00005D55466408_original.bin R4C2J7S8B 56/1/MG1CS201/11/MG1CS201_BX8TUE_R4C2J7S8B//R4C2J7S8B///
Gen2 00005D55467805_b58o1_original.bin R4C2J7V5B 56/1/MG1CS201/11/MG1CS201_BX8TUE_R4C2J7V5B//R4C2J7V5B///
Gen2 00005D55467805_original.bin R4C2J7V5B 56/1/MG1CS201/11/MG1CS201_BX8TUE_R4C2J7V5B//R4C2J7V5B///
Gen2 00005D55502807_b58o1_original.bin R4C2L857B 56/1/MG1CS201/11/MG1CS201_BX8TUE_R4C2L857B//R4C2L857B///
Gen2 00005D55503705_b58o1_original.bin R4C2L875B 56/1/MG1CS201/11/MG1CS201_BX8TUE_R4C2L875B//R4C2L875B///
Gen2 00005D55503C05_b58o1_original.bin R4C2L8N5B 56/1/MG1CS201/11/MG1CS201_BX8TUE_R4C2L8N5B//R4C2L8N5B///
Gen2 00005D55504807_b58o1_original.bin R4C2L8P7B 56/1/MG1CS201/11/MG1CS201_BX8TUE_R4C2L8P7B//R4C2L8P7B///
Gen2 00005D55504809_b58o1_original.bin R4C2L8P9B 56/1/MG1CS201/11/MG1CS201_BX8TUE_R4C2L8P9B//R4C2L8P9B///
Gen2 00005D5550480C_b58o1_original.bin R4C2L8PCB 56/1/MG1CS201/11/MG1CS201_BX8TUE_R4C2L8PCB//R4C2L8PCB///
Gen2 00005D55505008_b58o1_original.bin R4C2L8S8B 56/1/MG1CS201/11/MG1CS201_BX8TUE_R4C2L8S8B//R4C2L8S8B///
Gen2 00005D55506406_b58o1_original.bin R4C2L8V6B 56/1/MG1CS201/11/MG1CS201_BX8TUE_R4C2L8V6B//R4C2L8V6B///

Application documentation (aka Funktionsrahmen)

Unfortunately, functions described in the A2L are not always simple, can have dozens of inputs and outputs and what is happening inside them is not guessable. In this case, and for more specialist tuning goals, you need a Funktionsrahmen (FR or FRM), which is a PDF export of the computation paths in the DME generated from the (Matlab Simulink) code. Important sections might also contain text and diagrams that help to explain the strategies.

For any given software version, the DME code consists of two levels, each with its own FR:

  1. A supplier layer provided by Bosch. In general, this is focused on low-level support functions. It can be somewhat useful for tuning, for example, knock detection is covered in this document.
  2. A BMW application layer. This has a lot of useful information about timing, lambda control, fuel injection and turbo control.

Unfortunately, FRs can be hard to obtain, especially in the software version of your choosing and many people work from FRs that relate to versions only somewhat related to their car.

ASAP2 Demo

This is an awesome tool from https://jnachbaur.de/ASAP2Demo/ASAP2.html which lets you browse through A2L files and the calibration bins based on those.

A2Ls are loaded through the file-->open menu option and bins are loaded via the file-->load data file menu option.

Because it is based on the A2L, you can use it to glance quickly at any ECU object without having to import or convert (a common impediment with WinOLS and TunerPro). So, for example, if you see a map called KF_AUSY_TURB with an axis representing MAF, in the A2L, ASAP2Demo let's you see the map quickly and determine if you want to import it into tunerpro or other tool (more on this below).

One specific and important use for ASAP2Demo is to check the verion number of a bin file. This is held in a value called CustDiag_dDatasetVer_C:

Finally, ASAP2Demo supports all the characteristic types and axis types in the A2L standard, which makes it good for looking at non-numeric data.

QTranslate

QTranslate, from https://qtranslate-app.web.app/, is a very useful app that allows quick and easy translation of German text without having to switch to google translate.

Getting tunes off of your car

If you have a dialled-in tune on your car, it can be useful to read it off the ECU.

For gen 1 cars using Bosch MG1 with the SPC5777M chipset I have had success with ECU Bench tool. This is an inexpensive tool which works for reading ECUs without bricking them.

That said, a more effective workflow is to use the bench tool to read the DME but then write with the common flashing platforms like MHD since they support burbles, switchable fuel pumps, downpipes, etc. In order to do this, bear in mind that the bench reader reads a wider ROM segment off the chipset while the calibration space used for tunerpro bins are at an offset within this (e.g. 0x40001).

There are other more expensive professional options available, like autotuner and bitbox.

Tuning with MHD

Jobs involving antilag, flexfuel and map switching require editing of custom MHD tables which are not in any BMW A2L. MHD's approach here is to use tuner pro and they provide a well organized repo of tuner pro XDFs to support this. The XDF can be found at https://github.com/dmacpro91/BMW-XDFs.

The XDFs include table definitions for some but not all tables you might want to modify and they only include a small subset of tables you might want to inspect when trying to understand DME objects in context. For that reason, a good workflow with MHD is to

  1. Use the A2L and ASAP2Demo (or WinOLS if you have a licence) to browse and understand DME settings in the large.
  2. Import objects into XDF if needed and complete edits there.
  3. Flash with MHD Flasher.


TunerPro itself is available from https://www.tunerpro.net/. Generally, you want the TunerPro RT version. Consider registering the software at https://www.tunerpro.net/registration.htm, especially if you use the software to develop a working tune for your car.