BMW M135i tuning

BMW M135i remapping in Bristol, Somerset and South Wales

There are two very different M135is: the rear-drive F20 with an N55 straight-six, and the four-cylinder F40 with xDrive. We tune both. We come to you from our Weston-super-Mare base, across Bristol, Somerset, Gloucestershire, Wiltshire, South Wales and parts of Devon and Dorset.

BMW M135i generations we tune

Factory figures vary by market and year. We confirm your car's exact ECU and software before quoting.

F20/F21 M135i (2012–2016)

N55 3.0 turbo straight-six, 320hp and later 326hp, 450Nm.

F40 M135i xDrive (2019 on)

B48 2.0 turbo four-cylinder, 306hp and 450Nm. Most need an ECU unlock first.

Two generations, two characters

The F20's N55 responds strongly to Stage 1; M135is we have tuned went to around 380hp, with and without a gearbox tune.

The F40 uses a locked Bosch MG1 ECU, which we unlock on site before tuning. Its B48 engine also tunes very well: from 306hp and 450Nm, our Stage 1 targets 335hp and 500Nm and Stage 2 350hp and 530Nm. Figures are approximate targets and depend on the car's condition, fuel quality and supporting hardware.

Gearbox tuning

The F20 uses the ZF 8-speed (or a manual) and the F40 an 8-speed Steptronic. We map both to suit the engine.

Examples of our BMW M135i work

Related BMW pages

Common questions

Is the M135i a six-cylinder?

The 2012 to 2016 F20 M135i is a six-cylinder N55. The 2019-on F40 M135i is a four-cylinder B48.

Does the F40 M135i need an unlock?

Most do. We unlock it on site, usually in the same visit as the tune.

Recent BMW jobs

BMWs we have tuned, with their figures.

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Customer feedback

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