Page organisation in this revision
- Page type
- Technical article
- Subject
- Tuning
- Parent
- Siemens MSS52
- Applies to
- Siemens MSS52
- Tool groups
- None
- Manufacturers
- BMW
Changes from revision 1 to revision 1
Removed text is struck through; added text is highlighted.
Scope and base map records
These observations describe Ken Malinich’s pinned XDF for the software records on the MSS52 hub. They describe the file’s definitions rather than independently verified ECU selection logic.
SymbolStored valuesDimensions and axesXDF conversionKF_TI_N_RF8-bit factor18 RPM columns × 12 relative-filling rowsx/128KF_TI_N_RF_VL8-bit factor18 RPM columns × 3 relative-filling rowsx/128
The source labels relative filling as % RF using x/10 for its stored axis values. MSS52 XDF.
Interpret the factor before applying a correction
With the stated factor equation, raw 128 displays as 1.0 and raw 144 as 1.125. That is a 12.5% difference in this factor. It does not by itself calculate a delivered lambda: the underlying fuel calculation, active state, other corrections, injector behaviour and learned state still need evidence.
The source comment for the steady-state item speculates about interpolation during transitions. Retain that uncertainty when writing about the transition; separate a source hypothesis from a measured state change.
Other fuel and lambda entry points
AreaNames present in the XDFWarm-upKF_TI_TMOT_TML_WLInjection end angleKF_TI_ENDE_N_RFFull-load cylinder correctionsKL_TI_N_VL_ZYL1 through KL_TI_N_VL_ZYL8Adaptation conditionsK_LAA_TMOT_MIN, K_LAA_TMOT_MAX, KL_LA_NAdaptation boundsK_LAA_FMIN, K_LAA_FMAX
Use the exact source item to establish dimensions, units and qualifiers for each name. MSS52 XDF.
Suggested validation
Begin with stable temperature and operating state, compare both banks where the logger exposes them, and preserve the original feedback/adaptation values. Check starts, warm-up, stable part load and transitions as separate questions. For a high-load comparison, retain an appropriate measured lambda and fuel-delivery evidence.
When changing injectors, keep flow, pressure, latency and minimum delivery data distinct from map multipliers. A change in a fuel factor is not a substitute for identifying the injector or establishing the actual fuel pressure.
Sources and evidence
Original Tuning Wiki reference notes. Definition data and source-code observations are identified as such; they do not establish runtime behaviour or a tested calibration. Validation suggestions and worked arithmetic are editorial guidance. Sources checked 10 November 2026.
MSS52: Ken Malinich (kdm) and the contributors credited by his project; copyright © 2019 Ken Malinich, MIT licence.
MSS52 project and software coverage — commit a04c0d24fe63.MSS52 XDF — commit a04c0d24fe63.
Rendered revisions
Open each version to inspect formatting, tables and photographs.
Revision 1: MSS52 fueling and lambda
Scope and base map records
These observations describe Ken Malinich’s pinned XDF for the software records on the MSS52 hub. They describe the file’s definitions rather than independently verified ECU selection logic.
| Symbol | Stored values | Dimensions and axes | XDF conversion |
|---|
KF_TI_N_RF | 8-bit factor | 18 RPM columns × 12 relative-filling rows | x/128 |
KF_TI_N_RF_VL | 8-bit factor | 18 RPM columns × 3 relative-filling rows | x/128 |
The source labels relative filling as % RF using x/10 for its stored axis values. MSS52 XDF.
Interpret the factor before applying a correction
With the stated factor equation, raw 128 displays as 1.0 and raw 144 as 1.125. That is a 12.5% difference in this factor. It does not by itself calculate a delivered lambda: the underlying fuel calculation, active state, other corrections, injector behaviour and learned state still need evidence.
The source comment for the steady-state item speculates about interpolation during transitions. Retain that uncertainty when writing about the transition; separate a source hypothesis from a measured state change.
Other fuel and lambda entry points
| Area | Names present in the XDF |
|---|
| Warm-up | KF_TI_TMOT_TML_WL |
| Injection end angle | KF_TI_ENDE_N_RF |
| Full-load cylinder corrections | KL_TI_N_VL_ZYL1 through KL_TI_N_VL_ZYL8 |
| Adaptation conditions | K_LAA_TMOT_MIN, K_LAA_TMOT_MAX, KL_LA_N |
| Adaptation bounds | K_LAA_FMIN, K_LAA_FMAX |
Use the exact source item to establish dimensions, units and qualifiers for each name. MSS52 XDF.
Suggested validation
Begin with stable temperature and operating state, compare both banks where the logger exposes them, and preserve the original feedback/adaptation values. Check starts, warm-up, stable part load and transitions as separate questions. For a high-load comparison, retain an appropriate measured lambda and fuel-delivery evidence.
When changing injectors, keep flow, pressure, latency and minimum delivery data distinct from map multipliers. A change in a fuel factor is not a substitute for identifying the injector or establishing the actual fuel pressure.
Sources and evidence
Original Tuning Wiki reference notes. Definition data and source-code observations are identified as such; they do not establish runtime behaviour or a tested calibration. Validation suggestions and worked arithmetic are editorial guidance. Sources checked 10 November 2026.
MSS52: Ken Malinich (kdm) and the contributors credited by his project; copyright © 2019 Ken Malinich, MIT licence.
Revision 1: MSS52 fueling and lambda
Scope and base map records
These observations describe Ken Malinich’s pinned XDF for the software records on the MSS52 hub. They describe the file’s definitions rather than independently verified ECU selection logic.
| Symbol | Stored values | Dimensions and axes | XDF conversion |
|---|
KF_TI_N_RF | 8-bit factor | 18 RPM columns × 12 relative-filling rows | x/128 |
KF_TI_N_RF_VL | 8-bit factor | 18 RPM columns × 3 relative-filling rows | x/128 |
The source labels relative filling as % RF using x/10 for its stored axis values. MSS52 XDF.
Interpret the factor before applying a correction
With the stated factor equation, raw 128 displays as 1.0 and raw 144 as 1.125. That is a 12.5% difference in this factor. It does not by itself calculate a delivered lambda: the underlying fuel calculation, active state, other corrections, injector behaviour and learned state still need evidence.
The source comment for the steady-state item speculates about interpolation during transitions. Retain that uncertainty when writing about the transition; separate a source hypothesis from a measured state change.
Other fuel and lambda entry points
| Area | Names present in the XDF |
|---|
| Warm-up | KF_TI_TMOT_TML_WL |
| Injection end angle | KF_TI_ENDE_N_RF |
| Full-load cylinder corrections | KL_TI_N_VL_ZYL1 through KL_TI_N_VL_ZYL8 |
| Adaptation conditions | K_LAA_TMOT_MIN, K_LAA_TMOT_MAX, KL_LA_N |
| Adaptation bounds | K_LAA_FMIN, K_LAA_FMAX |
Use the exact source item to establish dimensions, units and qualifiers for each name. MSS52 XDF.
Suggested validation
Begin with stable temperature and operating state, compare both banks where the logger exposes them, and preserve the original feedback/adaptation values. Check starts, warm-up, stable part load and transitions as separate questions. For a high-load comparison, retain an appropriate measured lambda and fuel-delivery evidence.
When changing injectors, keep flow, pressure, latency and minimum delivery data distinct from map multipliers. A change in a fuel factor is not a substitute for identifying the injector or establishing the actual fuel pressure.
Sources and evidence
Original Tuning Wiki reference notes. Definition data and source-code observations are identified as such; they do not establish runtime behaviour or a tested calibration. Validation suggestions and worked arithmetic are editorial guidance. Sources checked 10 November 2026.
MSS52: Ken Malinich (kdm) and the contributors credited by his project; copyright © 2019 Ken Malinich, MIT licence.