When BMW unveiled the new M135 last year, we were disappointed to see a detuned version of the “B48” engine. The turbocharged 2.0-liter gasoline mill makes only 296 hp in Europe, where the hot hatch must meet stringent emissions regulations. Elsewhere, the uncorked four-cylinder mill delivers the full 312 hp. Seeing the glass half full, torque remains unchanged at 295 lb-ft (400 Nm).
In European flavor, the top version in the 1 Series is down on power by 6 hp and 37 lb-ft (50 Nm) compared to the old M135i “F40.” Now that we’ve mentioned the numbers published by BMW on paper, let’s see how much power the engine really makes. Evolve Automotive borrowed AUTOID’s M Performance 1er and strapped it onto a dyno at MSL Performance in the UK.
After no fewer than six dyno runs, the M135 maxed out at 286 hp at the wheels during the penultimate test. The third run achieved the highest torque, at 299 lb-ft (405 Nm). Mind you, these numbers represent the horsepower and torque available at the wheel. Assuming a 12% drivetrain loss, the engine makes roughly 320 hp at the crank. The torque delivered at the wheels is already higher than the official number listed by BMW.
Although the new M135 pumps out more power than advertised, it’s still a far cry from the old M140i. The larger 3.0-liter “B58” was good for 335 hp and 369 lb-ft (500 Nm). BMW routed output to either the rear wheels or to all four. Granted, only left-hand-drive cars came with xDrive, as packaging constraints forced BMW to skip the RHD configuration with AWD.
BMW doesn’t offer this choice since the new M135 is xDrive-only. You’re stuck with a dual-clutch, seven-speed automatic transmission, whereas the defunct M140i let buyers row their own gears with a six-speed manual. Perhaps we should be thankful there’s still a sporty version of the 1 Series rather than lamenting about the good ol’ days.
Video: Evolve Automotive / YouTube
