BMW B58 engine tuning

BMW B58 remapping in Bristol, Somerset and South Wales

The B58 3.0 turbo straight-six is one of the best tuning engines BMW has built. It powers everything from the M140i to the Z4 M40i, and we tune it across the range. We come to you from our Weston-super-Mare base, across Bristol, Somerset, Gloucestershire, Wiltshire, South Wales and parts of Devon and Dorset.

BMWs with the B58 engine

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

M140i and M240i (F20/F22)

340hp and 500Nm.

340i and 440i (F30/F32)

326hp and 450Nm.

M340i and M440i (G20/G22)

374hp and 500Nm.

540i (G30)

340hp and 450Nm.

X3 M40i and X4 M40i (G01/G02)

360hp and 500Nm.

Z4 M40i (G29)

340hp and 500Nm; the Toyota GR Supra shares the engine.

Why the B58 tunes so well

The B58 has a strong closed-deck block, an efficient twin-scroll turbo and a robust fuel system, so it makes big, reliable gains from software alone. Stage 2 builds on that with supporting hardware such as downpipes and intakes.

Later B58s in cars built from around mid-2020 often have locked Bosch MG1 ECUs, which we unlock on site before tuning.

Gearbox tuning

Most B58 cars use the ZF 8-speed automatic, which we tune to raise torque limits and sharpen shifts. Some M140i and M240i models have a 6-speed manual.

Examples of our BMW B58 work

Related BMW pages

Common questions

Which BMWs have the B58 engine?

Among others: the M140i, M240i, 340i, M340i, 440i, M440i, 540i, 740i, X3 and X4 M40i, X5 and X6 xDrive40i and the Z4 M40i, plus the Toyota GR Supra 3.0.

Does my B58 need an ECU unlock?

Many cars built from around mid-2020 do. We confirm it from your registration and unlock it on site if needed.

Recent BMW jobs

BMWs we have tuned, with their figures.

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Customer feedback

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