The KFMIOP torque map is one of the most consequential tables inside the Bosch MEG 1.1 ECU fitted to every Smart Roadster 452. It defines the theoretical optimal torque the engine should produce at any given load and RPM point — acting as the benchmark against which every other torque-related calculation in the ECU is measured. If you have ever wondered why two Roadsters with identical boost pressure can feel completely different to drive, or why a remap that only touches fuelling still changes throttle response, KFMIOP is almost certainly part of the answer. This article explains what the map is, how it works, how it interacts with surrounding tables, and why understanding it is essential for anyone remapping the 698cc engine correctly.
What Is KFMIOP and Where Does It Live?
KFMIOP — shorthand derived from Bosch’s internal naming convention for Kennfeld Motormoment Indiziert Optimal, meaning indicated optimal engine torque map — is a two-dimensional lookup table stored in the FLASH memory of the MEG 1.1. Its axes are engine speed (RPM) on one dimension and relative air charge (the ratio of actual to maximum cylinder fill, expressed as a percentage) on the other. The cell values represent the optimal indicated torque in Newton-metres that the ECU expects the engine to deliver under those exact conditions.
The MEG 1.1 uses a torque-based architecture, which means the driver’s throttle input is not wired directly to fuelling or boost targets. Instead, the ECU first converts the accelerator pedal position into a torque demand, and then calculates what combination of ignition timing, fuelling and boost is needed to satisfy that demand. KFMIOP is the reference table that tells the ECU what the engine is physically capable of at each operating point — it is the ceiling, not the request. To understand the broader framework this map operates within, it helps to first read about how the MEG 1.1 manages all its subsystems as a coordinated whole.
How KFMIOP Differs From the Torque Demand Maps
A common point of confusion is conflating KFMIOP with the driver demand tables. The driver demand maps (sometimes labelled KFMIRL or similar in the Bosch naming tree) translate pedal position into a requested torque value. KFMIOP does something subtly different: it declares what the engine should be capable of producing optimally — with correct ignition timing at the MBT (minimum advance for best torque) point and an ideal air-fuel ratio — at every load and speed combination.
If the actual indicated torque derived from combustion pressure modelling falls below the KFMIOP reference value by more than a calibrated tolerance, the ECU treats this as a fault condition or as evidence that something has degraded — a lean mixture, retarded timing due to knock, or a wastegate that is not holding target boost. This makes KFMIOP an active participant in the ECU’s closed-loop correction strategy, not just a passive lookup. It is the yardstick against which real combustion quality is continuously judged.
This relationship between boost target and actual torque output is particularly important on the 698cc, where the turbocharger is operating close to its efficiency boundary at higher load points. For a deeper look at that relationship, our article on how boost pressure translates into torque on the 698cc explains the physics involved.
The KFMIOP Axis Structure on the MEG 1.1
RPM Breakpoints
The RPM axis on the standard MEG 1.1 KFMIOP table typically runs from idle (around 700 RPM) to the rev limiter region (approximately 6,500 RPM), with breakpoints concentrated in the mid-range where the torque curve is steepest and most sensitive to calibration. The spacing is not uniform — there are more breakpoints between 2,000 and 4,500 RPM than at the extremes, reflecting where the turbo builds boost most aggressively and where fuelling accuracy matters most.
Load Axis (Relative Air Charge)
The load axis represents relative air charge (rl), expressed as a dimensionless ratio from 0 to 1 (or 0 % to 100 %). A value of 1.0 means the cylinder is as full as it can be at atmospheric pressure. Because the 698cc is turbocharged, it can exceed 1.0 — values above 1.0 represent boosted conditions where the charge mass exceeds naturally-aspirated maximum. This is critical context for interpreting KFMIOP cell values: the highest load rows in the table correspond to peak boost operation, and those cells carry the largest torque figures.
Cell Values and Units
Cell values are stored in Newton-metres of indicated torque — the torque calculated from cylinder pressure, before accounting for friction, auxiliary loads or drivetrain losses. Indicated torque is always higher than the brake torque measured at the flywheel. When tuners refer to modifying KFMIOP, they are working with these indicated values; the gap between indicated and brake torque on the 698cc is typically 15–20 Nm across the operating range.
Why KFMIOP Must Be Modified When Remapping
This is where KFMIOP becomes directly relevant to anyone considering a remap. If you increase boost pressure, advance ignition timing or enrich fuelling to extract more power, the engine will physically produce more indicated torque than the stock KFMIOP values allow for. The ECU will detect the discrepancy — actual torque exceeding the optimal reference — and can respond by pulling ignition timing, requesting the wastegate to dump boost, or flagging a torque monitoring fault. The result is that boost-based power gains are partially or wholly suppressed by the ECU’s own torque monitoring logic.
A correctly executed remap therefore requires KFMIOP to be raised in proportion to the increased capability of the engine at each load and RPM point. This is not a simple percentage uplift applied uniformly — the optimal torque changes shape across the rev range as boost builds, peaks and tapers. At low RPM where the turbo is spooling, KFMIOP values are modest and the gradient is steep. At peak torque RPM (typically 3,000–4,000 RPM on the 698cc), the values reach their maximum. Above that, as the engine approaches the efficiency limits of the Garrett 1238S, the KFMIOP values must taper accurately or the ECU will permit conditions that push the turbo into surge.
Critically, modifying KFMIOP also requires correct checksum recalculation. The MEG 1.1 performs integrity checks on its FLASH contents at startup; a KFMIOP edit without a valid checksum will cause the ECU to reject the flash or revert to a fallback state. Our guide on why flash operations fail without correct checksum correction covers this in full technical detail.
KFMIOP and the Softouch Gearbox: A Critical Interaction
The MEG 1.1 does not operate in isolation. On the Smart Roadster, the ECU communicates torque information to the Softouch automated manual gearbox controller. During gearshifts, the Softouch requests a temporary torque reduction from the engine ECU — a standard technique used to reduce drivetrain shock and protect the clutch engagement. The engine ECU uses KFMIOP as part of the reference framework for calculating how much it should reduce torque and when it is safe to restore it.
If KFMIOP has been raised to reflect a remapped engine but the Softouch calibration has not been considered, the torque reduction requests during shifts may become poorly timed or insufficient — leading to harsh gear engagement, clutch slip or drivetrain shock. This is a frequently overlooked consequence of incomplete remaps. Understanding how the Softouch actuator responds to increased torque from the engine is essential reading for anyone planning a serious power upgrade, because the gearbox side of the equation matters as much as the engine side.
At higher torque levels, the stock clutch itself becomes the limiting factor. If KFMIOP values are pushed aggressively without a corresponding clutch upgrade, the physical clutch disc will slip under the load the ECU has now permitted the engine to produce. For anyone tuning toward the upper limits of what the 698cc can deliver, understanding why the standard clutch gives up above a certain torque threshold should inform the entire build strategy.
Stock KFMIOP Values Across the Four Variants
The four production variants of the Smart Roadster — 45 kW Lite, 60 kW standard, 66 kW SB2 Brabus and 74 kW full Brabus — each have different firmware calibrations, and their KFMIOP tables reflect the different boost targets and power outputs of each variant.
- 45 kW Lite: Lowest KFMIOP values throughout. Peak indicated torque reference is modest, reflecting the reduced boost target of 0.89 bar and the absence of an oil cooler. The low ceiling is intentional — it is a thermal protection measure as much as a commercial differentiation.
- 60 kW standard: A more aggressive table, particularly in the 2,500–4,000 RPM range where the higher boost target (1.09 bar) allows a meaningfully larger charge mass. This is the most common donor calibration for remapping work.
- 66 kW SB2 Brabus: Noticeably higher values at mid-to-high load, reflecting 1.33 bar boost. The shape of the KFMIOP curve changes here — the table is optimised for the broader torque plateau that the SB2 calibration delivers.
- 74 kW full Brabus: The highest stock KFMIOP values in the range. Peak indicated torque references approach the thermal and mechanical limits of the standard engine components at 1.43 bar boost, leaving little margin for further KFMIOP increases without addressing cooling and bottom-end strength.
Understanding these differences matters when a tuner is working from a 60 kW base map and targeting Brabus-level or beyond-Brabus power levels. Simply copying KFMIOP values from a Brabus calibration into a 60 kW file is not sufficient — the surrounding maps (injection, ignition, boost control) must all be consistent with the new KFMIOP reference, or the torque monitoring logic will be internally contradictory.
Common Mistakes When Editing KFMIOP
Several recurring errors appear in DIY and poorly executed professional remaps of the MEG 1.1 when KFMIOP is involved:
- Raising KFMIOP without raising boost targets: The ECU will permit higher torque demand but the engine cannot physically deliver it, causing the torque monitoring to hunt and the ignition to be used as a blunt instrument to bridge the gap — leading to retarded timing, heat and inefficiency.
- Raising KFMIOP uniformly across all cells: A flat percentage increase ignores the non-linear relationship between charge mass, combustion efficiency and RPM. The result is a map that is correct at some operating points and dangerously incorrect at others.
- Failing to match KFMIOP to the ignition tables: KFMIOP represents optimal torque at MBT timing. If the ignition map does not provide MBT timing at those points, the engine will not achieve the KFMIOP reference, and the ECU will continuously interpret normal operation as a degraded condition.
- Forgetting the checksum: As noted above, any FLASH edit including KFMIOP requires valid checksum recalculation. Without it, the modified firmware will not load correctly.
KFMIOP in the Context of a Professional Remap
A professionally developed remap for the Smart Roadster 452 treats KFMIOP as one layer in a coherent calibration stack. Boost targets are set first, based on what the Garrett 1238S can deliver efficiently and what the engine components can tolerate. Fuelling and ignition tables are then built around those targets. KFMIOP is calibrated to match the resulting indicated torque curve — neither higher nor lower than what the other maps will actually produce. The result is an ECU that is internally consistent: its reference for what the engine should do exactly matches what the engine is doing.
This coherence is what separates a remap that makes reliable, repeatable power from one that makes peak power on a dyno but behaves erratically on the road. Our overview of what a Stage 1 remap actually delivers in real-world power gains covers how these calibration choices translate into measurable results at the wheels. If you are considering a remap and want to understand the full picture of what our maps target, the tuning packages available at smartroadster.tech detail exactly what each stage modifies and what gains to expect.
The KFMIOP torque map is not a peripheral detail in the MEG 1.1 calibration — it is a load-bearing element of the entire torque management architecture. Every power gain you extract from the 698cc must be reflected accurately in KFMIOP, or the ECU will work against the very changes you have made. Understanding its axes, its role in torque monitoring and its interaction with the Softouch gearbox is the difference between a remap that genuinely improves the car and one that creates as many problems as it solves. Approach it with the respect it deserves, and the 698cc engine will reward you with power delivery that is both stronger and more consistent than the factory calibration ever allowed.
