BMW M140i F21: Stage 1 + xHP Stage 3, 439bhp & 632Nm

This BMW M140i 3-door (F21) came in for our Stage 1 custom dyno tune for its B58 3.0 straight-six, with an xHP Stage 3 calibration for its ZF 8-speed automatic, both developed on the same visit.

The numbers

On the baseline run it made 348.7bhp and 541Nm. With our calibration and xHP Stage 3 it made 439.1bhp and 632Nm, with 378.4bhp at the wheels. That is 90.4bhp and 91Nm more:

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 it.

More torque than a G87 M2

BMW’s own G87 M2 makes 550Nm, or 600Nm for the later automatic. Tuned, this M140i holds over 600Nm from around 2,600 to 3,750rpm, with 70Nm or more extra torque from around 2,500rpm to the top of the stock run. Standard, its power flattens out at around 348bhp from 5,500rpm; tuned, it keeps pulling to 439bhp at around 6,000rpm, with 80bhp or more over standard from around 5,500rpm to the top of the stock run.

The gearbox, tuned with the engine

xHP Stage 3 was flashed into the ZF 8-speed on the same visit. It removes the factory torque limiter and raises line pressure for the extra torque, with quicker shifts in D and harder, faster shifts in Sport and Sport+, 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 M140i? See our BMW 1 Series tuning figures and B58 tuning page, check your car’s gains and price, or read about tuning the M140i and M240i and the M240i G42 we have tuned.