BMW M5 Competition F90: Twin-ECU Unlock, Stage 1 + xHP Stage 3, 682bhp & 863Nm

This 2022 BMW M5 Competition (F90) came in for our Stage 1 custom dyno tune for its S63 4.4 twin-turbo V8, with an xHP Stage 3 calibration for its 8-speed M Steptronic gearbox, both developed on the same visit.

Both ECUs unlocked in-house first

The S63 V8 runs two ECUs, and on a car built after June 2020 both are locked, so neither can be read or tuned through the OBD port as it comes. We unlocked both in-house on our own bench, then carried straight on with the calibration.

The numbers

On the baseline run it made 621.3bhp and 801Nm. With our calibration and xHP Stage 3 it made 682.5bhp and 863Nm, with 595.4bhp at the wheels. That is 61.2bhp and 62Nm more:

The car arrived with an aftermarket exhaust and intakes already fitted. The baseline and the final runs were both done with them on, and the calibration was developed around them, so the difference above is what our tune added to this car as it came in.

Watch the full dyno run

This is the final pull on our dyno, filmed from behind the car, from the start of the run right through to the end. Tap Sound on to hear the V8.

Over 850Nm from 2,750 to 4,750rpm

The peak is only part of it. Tuned, this M5 holds over 850Nm from around 2,750 to 4,750rpm, where the stock run only touched 800Nm for a moment at around 2,900rpm. It carries 50Nm or more extra from around 2,600rpm upward and close to 100Nm more at 4,500rpm, with around 60bhp more than standard from about 4,300rpm and over 650bhp from around 5,800 to 6,750rpm. In normal driving that is the part you feel: it pulls harder through the mid-range and holds on for longer in every gear.

The gearbox, tuned with the engine

xHP Stage 3 was flashed into the 8-speed M Steptronic on the same visit. It removes the factory torque limiters and reworks the shift logic across the three Drivelogic modes: smoother shifts in Drivelogic 1, the sharpest shifts in Drivelogic 3 and stronger blip downshifts, so the engine and gearbox are calibrated as one package instead of two separate jobs.

How it was done

Diagnostics and a health check first, then baseline runs on our 4WD linked dyno with live data logging. The engine calibration was built from there with repeated runs, the gearbox was flashed with xHP Stage 3, and the final pulls verified the result. No generic files: a calibration written for this car, proven on our dyno.

Got an M5? See our BMW M5 tuning figures and how we unlock twin-ECU V8s on our ECU unlocking page, check your car’s gains and price, or read about the M550i xDrive, another twin-ECU V8 we unlocked in-house and tuned with xHP.