Estimated Power Slot & Virtual Dyno
Estimate the horsepower and torque your engine is producing right now, from OBD2 fuel flow. After the drive, Virtual Dyno draws a power curve from the log. Both are free.
1.Overview
The Estimated Power slot calculates how much power the engine is making from the amount of fuel it's burning. No chassis dyno required — just an OBD2 adapter.
Values are estimates. Numbers calculated with the standard coefficient carry an "Uncorrected" badge. Calibrate the coefficient from real-world acceleration data (Premium) and the badge goes away, with values tuned to your car.
Save your drive logs and you can review them later as a power curve in Virtual Dyno.
2.What's shown
| Item | Description |
|---|---|
| POWER | Current estimated output (PS / HP / kW) |
| TORQUE | Current estimated torque (kgf·m / N·m / lb·ft). Shows "--" below 500 rpm |
| Max | Peak power and torque in the session, with the rpm they occurred at. Resets automatically when the OBD connection is closed (manual reset in the slot's detail settings) |
| Trend line | The last 15 seconds of output (large slot only) |
- Small slots show the power figure only; torque, Max and the trend line appear in the large slot.
- Units come in pairs: PS / kgf·m, PS / N·m, HP / lb·ft, kW / N·m. The default follows your language setting (HP / lb·ft for English).
3.How it's calculated
Power [PS] = fuel flow [L/h] × coefficient k Torque [kgf·m] = 716.2 × Power [PS] ÷ rpm
The standard k is derived from fuel density, heating value and a typical engine efficiency: about 3.7 for gasoline and 5.4 for diesel (PS per L/h). Fuel type follows your fuel settings.
Fuel flow comes through the same path as the Fuel Metrics slot: the ECU's fuel rate (PID 0x5E) when available, otherwise MAF, and for cars with neither, Speed-Density estimation from MAP, rpm, intake temperature and displacement.
Physically impossible readings (over 0.5 PS per cc of displacement) are treated as missing and never reach the peak or the trend line.
4.Virtual Dyno (power curve from a drive log)
On a record's detail screen, use the Route ⇄ Dyno toggle at the top left of the map block to see that drive's rpm-vs-power/torque curve.
Rather than looking for full-throttle pulls, it analyzes the whole drive and draws the upper envelope for each rpm. Peak power and torque are annotated with the rpm they occurred at.
The chart uses the same coefficient k as the slot, and shows the "Uncorrected" badge until calibrated.
5.Calibration (Premium)
Tap "Calibrate with this drive" at the bottom right of Virtual Dyno to re-measure k from that drive's acceleration data. Nothing to do while driving — record as usual and analyze afterwards.
Vehicle weight is required. Enter curb weight, occupants, cargo and transmission type (MT / AT / CVT) in the vehicle profile under "Vehicle info for power calibration".
The analysis compares the work the car actually did while accelerating (from speed change and mass) with the fuel it burned, and expresses the result as a ratio to the standard coefficient. You'll see something like "×0.88 / spread ±11% / partial-throttle, grade verified". Tap "Apply" and both the slot and Virtual Dyno switch to the calibrated value.
When accelerometer data is present, grades are detected and hill sections are excluded (from v1.3.4, G data is recorded automatically even without a G-meter slot). Older logs are treated as "grade unverified" and need more acceleration samples.
For best results, use a drive on flat roads that includes a few 40 → 80 km/h accelerations. Drives with only light acceleration tend to produce a lower coefficient.
Calibration is saved per vehicle profile. Use "Reset calibration" in the slot's detail settings to return to the standard coefficient.
The slot and Virtual Dyno are free. Only calibration from real-world data is a Premium feature.
6.Accuracy and caveats
- Estimates assume a typical engine efficiency. Even for the same car, load (throttle) and air-conditioning shift the result by a few percent.
- For cars that need Speed-Density (no fuel rate and no MAF), displacement and volumetric efficiency in the fuel settings feed directly into the result. Leaving displacement at its default (2000 cc) gives wildly wrong numbers — set your actual displacement.
- For diesel cars, set fuel type to Diesel; the gasoline setting reads low.
7.On Desktop
Desktop v1.0.16 and later offers the Estimated Power slot in playback and overlay export, and Virtual Dyno on the record detail screen.
Records synced from the mobile app v1.3.4 or later carry the coefficient calibrated on your phone, shown as "Corrected" on Desktop. (Calibration itself is mobile-only.)
8.FAQ
It doesn't match the catalog horsepower.
The estimate is "power being produced right now", derived from fuel consumption — a different measurement from a catalog peak figure. After calibration, most cars land in the same ballpark as the catalog value.
Is it free?
The slot and Virtual Dyno are free. Calibration from real-world data is a Premium feature.
What happens to calibration if I cancel Premium?
Values return to the standard coefficient and the "Uncorrected" badge. Your calibration data is kept and comes back when you resubscribe.
Can I view Virtual Dyno for older logs?
Yes. Logs recorded before v1.3.4 have no accelerometer data, so calibration treats them as "grade unverified".
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