The MED17 gasoline torque conversion path is a 7-step chain: driver request (DAMOS DrvDemA / DrvDemA_tqCluDemAceped on MED17/MG1) → % of max N·m → N·m with friction and thermal losses added → torque limit check (MDMAXNMOT / LimTqEco_tqCluEcoMax) → percentage of technical flow → mg of air per cycle via volumetric efficiency map (KFMIRL) → divided by combustion chamber size → desired boost pressure. Fuel injection is calculated against flow (pressure × RPM), not pressure alone — pressure is just the monitoring signal.
Below: the full chain walked through with a 1.2L MED17 example.
This is the text summary. Paid attendees of our Q&A #1 (April 2026) got my live walkthrough — I demonstrated this on a real ECU binary in WinOLS, pointing to actual maps, scrolling DAMOS folders, showing byte-level changes. For the full gasoline calibration approach, see our Chip Tuning Gasoline course →. Register free for our next Open Q&A → — live with me, agenda forming.
The question — from Q&A #1
Pavel asked during our first live Q&A:
“Gasoline engine — what does the full torque conversion path look like: driver request → torque structure → load → boost?”
I opened a MED17 file in WinOLS® and walked through each step on-screen with a calculator in hand.
The 7-step chain
The full path starts from the driver’s request — that’s just the map which is located here. The information coming from that map is the torque, as a percentage of the maximum technical torque. N·m_max multiplied by some percent gives us the torque (00:51:47).
Step 1 — Driver request map (+ paired monitoring)
The driver wish map (DAMOS folder DrvDemA — Driver demand acceleration, map DrvDemA_tqCluDemAceped on MED17/MG1) outputs a percentage of maximum technical torque (N·m max). At any given pedal position and RPM, the map returns a number like 50% — meaning “driver wants half of the engine’s theoretical peak torque.” The ECU multiplies this % by the known N·m_max constant to get the actual demand in Newton meters.
Note — I focused on the conversion math in this Q&A segment. The monitoring detail below is the natural companion to the diesel walkthrough in KB-08, translated to MED17/MG1 gasoline DAMOS conventions per Tuners Guild reverse-engineering work.
The monitoring gotcha most tuners hit first: MED17/MG1 gasoline uses a Level 2 EGAS runtime monitoring on the driver wish — a separate DAMOS map that the ECU compares against the main DrvDemA_tqCluDemAceped during driving. If you raise the main map but forget the monitor, the ECU throws a fault and drops into limp.
On gasoline, the monitoring lives under the MonDrvDem* folder family (Monitoring Driver Demand). The best-known variant is MonDrvDemA_tq in folder MonDrvDemAVW (Überwachung Fahrerwunscherfassung Gaspedal VW — monitoring driver wish acquisition gas pedal, VW example). Other OEMs running MED17/MG1 have their own MonDrvDem* variants with OEM-specific suffixes — same structure, different folder name. This family is gasoline-only — diesel uses a completely different monitoring convention (MoFLos*, see KB-08).
Not every MED17 variant ships the same set. What matters: before editing main DrvDemA_tqCluDemAceped, grep the entire DAMOS for MonDrvDem* folders and raise every matching monitor in parallel. One un-raised monitor will override the edit before you hit step 4.
Step 2 — Convert % demand → N·m
The percentage gets converted into either N·m directly or a percentage of technical flow (an intermediate representation). This translation is where the ECU first crosses into physical units it can reason about. The base quantity for this conversion lives in MDBAS (Berechnung der Basisgrößen für Momentenschnittstelle — base quantities for torque interface), specifically map KFMIOP (optimal engine torque map, TQ Optimal).
Step 3 — Add losses (friction + thermal)
We have friction losses. We have additional thermal losses, because the engine’s efficiency depends on actual temperature (00:52:43).
Before reaching the final demand, the ECU adds compensation for:
- Mechanical friction losses (bearings, valvetrain, accessory drives)
- Thermal efficiency losses (cold engine has different efficiency than fully warmed-up engine)
The goal: maintain the exact torque at the crank that the driver asked for, regardless of temperature and parasitic drag.
Step 4 — Check against torque limit (structural)
The adjusted demand is checked against two torque limits in parallel:
MDMAXNMOT(TQ limit main — Maximales indiziertes Drehmoment für Leistungsbegrenzung / max indicated torque for power limitation) — lives in folderMDRLMX. This is the structural cap.LimTqEco_tqCluEcoMax(target torque limitation at clutch) — lives in folderPtOpp(Torque limiter secondary). This is the fuel-economy secondary limit.
In WinOLS on MED17: “100% is just 65535” (16-bit representation, 2^16 - 1). The N·m_max constant (the map’s scale factor) tells you what 65535 actually means in physical units. If your demand hits 65535 on either map and you haven’t raised the ceiling, step 5 onwards uses clipped torque — the rest of the chain calculates against the limit, not the real demand.
Step 5 — Calculate max technical load
Using the example from the Q&A:
- Demand at this operating point: 220 N·m
- Torque limit coefficient: 0.51
220 / 0.51 = 430 N·m
So the max technical load at this operating point is 430 N·m and the demand (220 N·m) is about 50% of it. That “percentage of technical flow” is what step 6 converts.
Step 6 — Convert load → mg of air per cycle
The load map converts the % of technical flow into milligrams of air per combustion cycle via a slope-per-cycle conversion map — DAMOS KFMIRL (Kennfeld für Berechnung Sollfüllung / Volumetric Efficiency), living across folders MDFUE (Sollwertvorgabe für Luftmasse aus Sollmoment — air mass setpoint from target torque) and MDRLMX (Maximale Soll-Luftfüllung für Nennmoment — max target air fill for rated torque). In the Q&A example, ~1.01 mg/cycle corresponded to the 220 N·m demand.
Step 7 — Divide by combustion chamber size → desired boost
The ECU knows the engine’s displacement (stored constant). For the 1.2L example:
- Total displacement: 1.2 L
- Cylinders: 4
- Per-cylinder combustion chamber:
1.2 / 4 = 0.3 L = 300 cc - Required mg air per cycle × factor: 600
600 / 300 = 2 bar absolute
Atmospheric pressure = 1 bar, so 2 bar absolute = 1 bar boost (gauge) at that operating point. That’s the number the turbo wastegate controller targets.
Pressure vs flow
Remember — not only pressure is important for the system, but also flow. Flow is calculated as pressure multiplied by RPM, so the proper amount of fuel can be injected. Fuel is injected versus flow, not versus pressure (00:57:50).
| Parameter | What it measures | What it drives |
|---|---|---|
| Pressure (MAP) | Manifold absolute pressure | Monitoring — “is boost actually happening?” |
| Flow | Pressure × RPM | Fuel injection quantity |
At the same MAP reading, an engine at 2000 RPM moves half the air of the same engine at 4000 RPM. Fueling has to scale with flow, not pressure. If you only watch MAP, you’ll run rich at low RPM and lean at high RPM even though the pressure reads identical.
The 7-step chain as a reference card
1. Driver request map → % of N·m_max
2. Convert % → N·m (with optional % of technical flow intermediate)
3. Add losses (friction + thermal compensation)
4. Check against torque limit (structural cap via 65535 max)
5. Calculate max technical load → N·m
6. Convert to mg air per cycle (slope-per-cycle conversion map)
7. Divide by combustion chamber → bar absolute → bar boost
Stage 1 files that work clean have all 7 steps scaled together. The DTCs and limp-mode failures usually trace back to step 6 or 7 being edited without touching steps 1-4.
Where this matters for Stage 1+
For a clean MED17 gasoline Stage 1:
- Increase driver request map (step 1) → authorizes higher torque demand
- Verify torque limit isn’t clipping (step 4) → raise it if needed
- Scale load/mg air conversion (step 6) → matches the new demand
- Let boost target (step 7) follow from the math, don’t hand-tune boost as a standalone
Hand-tuning boost in isolation breaks the chain — the ECU’s flow calculation for fueling goes stale, and the resulting drivability issues trace back to Step 7 being edited without Steps 1-6.
Maps referenced in this guide
All map IDs below are Bosch gasoline DAMOS — applicable to MED17 and MG1. The “Deep dive” column links to related KB posts and the Tuners Guild EDC17 pillar article where the cross-platform torque structure pattern is explained.
| Concept | DAMOS Folder | Map ID | Deep dive |
|---|---|---|---|
| Driver wish — torque request at clutch | DrvDemA |
DrvDemA_tqCluDemAceped |
This KB (hub) |
Driver wish Level 2 monitoring — gasoline, OEM variants under MonDrvDem* family (VAG example shown; other OEMs have equivalent MonDrvDem* folders) |
MonDrvDemAVW |
MonDrvDemA_tq |
This KB (hub) |
| Base quantity / optimal engine torque | MDBAS |
KFMIOP (TQ Optimal) |
This KB (hub) |
| TQ limit main — max indicated torque for power limitation | MDRLMX |
MDMAXNMOT |
This KB (hub) |
| TQ limit secondary — target limit at clutch (fuel economy) | PtOpp |
LimTqEco_tqCluEcoMax |
This KB (hub) |
| Volumetric efficiency / load → mg air per cycle | MDFUE + MDRLMX |
KFMIRL |
This KB (hub) |
| Flow limiter (by intake manifold temp) — guardrail | BGRLMXS |
KFRLXT |
— |
| Compressor overspeed protection — guardrail | BGRLXVD |
KFVNTUXS |
— |
| Turbo outlet temp protection — guardrail | BGRLXVD |
KFVVTVATU |
— |
Parallel diesel platform: on EDC16/EDC17/MD1 the torque structure uses different naming (AccPed_trqEng / PhyMod_trq2qBas / EngPrt_trqLim) but the structural pattern is the same 7-step chain. For the diesel version see Blog #6 — Bosch EDC17 tuning guide DAMOS reference table.
Parallel diesel monitoring: the “raise driver wish without raising monitoring = fault” pattern exists on both platforms, but the DAMOS conventions are cleanly split. Gasoline monitoring lives under the MonDrvDem* family (Monitoring Driver Demand; OEM-specific suffixes like MonDrvDemAVW for VAG) — gasoline-only, never on diesel. Diesel monitoring lives under the MoF* umbrella, split across sibling folders: MoFDrDem_Co (Level 1 key-on integrity — contains MoFDrDem_rTrqEng, the 8-bit paired shadow of AccPed_trqEng) and MoFLos_Co (Level 2 runtime — contains MoFLos_trqEngLos 16-bit and MoFLos_rTrqEngLos 8-bit ratio). Which folders a given bin actually ships varies variant-to-variant — always survey before scaling. Same principle, different folder families. See KB-08 — EDC17C46 driver wish no-start for the diesel version.
Related on Tuners Guild
- Why the 21% math only delivers 10-15%: KB-02 Why 21% diesel math gives real 10-15% gain (forthcoming this week) — connects directly to Step 4 (torque limit) and hardware bottlenecks
- Synchronous monitoring (Step 4 context): KB-08 EDC17C46 driver wish no-start — the monitoring problem shows up at step 1 and step 4
- DENSO displacement swap (MAP vs MAF): KB-10 DENSO 2.0 → 2.5 MAF/MAP — same pressure-vs-flow distinction applies
- Full gasoline workflow: Chip Tuning Gasoline — Practice course
- Course pricing and bundles: See pricing →
Want the full MED17 workflow?
The 7-step torque conversion chain is chapter 4 of our Chip Tuning Gasoline Practice course. The full course walks each step in WinOLS on three different MED17 variants (MED17.5, MED17.5.20, MED17.5.25), including the torque limit structure, load conversion maps, and boost control calibration that turns this theory into a reliable Stage 1 file.
See the Chip Tuning Gasoline course →
Your turn
Working with a different MED17 variant — 17.5, 17.5.20, 17.5.25, 17.9.21? Or a non-MED17 gasoline ECU (SIMOS 18, Continental EMS, Siemens SID)? Post your experience:
- ECU variant + engine (displacement + cylinders)
- Which of the 7 steps you found the most confusing
- Whether your conversion math matched my chain, or you found variations
- Any DTC or limp-mode issue you traced back to breaking the chain
We’ll build a cross-ECU reference for the torque structure pattern.