Related model groups
MS4X links MS45 intake modeling, fueling and torque-based throttle control. Its entry points include:
| Area | Names to locate |
|---|---|
| Intake model | ip_eff_vol_slop_max; ip_eff_vol_slop_cam_vo; ip_eff_vol_slop_cam_vo_vim |
| Airflow request | ip_maf_sp |
| Reference torque / monitoring | ip_tqi_ref__n__maf; ip_tqi_ref_mon |
| DISA thresholds | c_n_vim_l; c_n_vim_h; c_fac_maf_max_vim |
| DISA zones | c_vimpwm_[1-6]; c_vim_av_[1-6] |
Bracketed labels abbreviate groups; the source describes six DISA zones. MS4X reference; MS4X reference.
Document physical and modeled airflow together
For a manifold, camshaft or forced-induction change, keep the original model, actual hardware and relevant sensor data in one comparison record. State the operating region being evaluated and identify which axes, values or units the proposal changes.
Compare pedal request, requested/actual throttle, airflow, load, lambda and available intervention evidence over the same event. A change in throttle behaviour is a reason to inspect the model relationships; it is not proof that a single request table needs a larger number.
Check actuator state against model state
Record the physical DISA installation, commanded state and any position/diagnostic evidence available. When comparing intake-model branches, identify which physical configuration each is intended to represent. Do not infer physical vane position from a numerical percentage without checking the exact definition and actuator convention.
Keep monitoring in the review
Compare the reference model and its monitoring counterpart whenever a change affects their shared representation. Keep the original values, conversion and axes so a reviewer can establish whether the two still describe the same operating conditions. Retain faults and limiting events in the evaluation record instead of treating their disappearance as the sole result.
Sources and scope
Original reference notes by Tuning Wiki, informed by the linked MS4X Wiki pages. MS4X Wiki contributors and the authors credited by each linked project remain the source authors. Sources checked 10 November 2026. Suggested validation steps and worked arithmetic are editorial guidance; they are not a tested calibration or a claim of hardware verification.
- Siemens MS45 (revision 23142).