Tuning · BMW M140i (F20 / F21)
M140i
B58 Gen 1
One of the great hot-hatch sleepers. Calibrated by hand from Stage 1 to a fully bespoke big-turbo build. Choose your package, send your build to Samuel, and get a tune that fits the way you actually drive.
Engine
B58 Gen 1
Stock
335 bhp · 500 Nm
Stage 3 ceiling
335 bhp
About this tune
The F20 / F21 M140i (2016-2019) is the LCI 1 Series hot hatch with the B58 Gen 1, the engine that replaced the N55-powered M135i. Stock is 335 bhp / 500 Nm, sent rear-wheel via the ZF 8HP. Available as the F20 5-door and the rarer F21 3-door, both sharing the identical drivetrain. Widely regarded as the last RWD 1 Series, and one of the most-tuned hot hatches in the UK, because the B58 Gen 1 underneath responds exceptionally well to a remap.
BMW M140i tuning
The BMW M140i (F20 / F21, 2011–2019) runs the B58 Gen 1 and leaves the factory at 335 bhp · 500 Nm, Rear-wheel drive, 8-speed ZF automatic. Samuel tunes the F20 5-door and F21 3-door to the same standard — every map hand-calibrated for the specific car, its fuel grade and its installed hardware, not a base file loaded and left. M140i Stage 1 alone takes it from 335 bhp · 500 Nm to 420 bhp · 600 Nm on the standard turbo, flashed over OBD on BM3, MHD or MG Flasher.
Add the Stage 2 hardware and the M140i targets 450 bhp · 650 Nm; from there the B58 Gen 1 stretches to around 1000 bhp on a hybrid or big-turbo build with supporting fuelling. Whichever stage suits the M140i, the file is delivered within 24 hours and is fully reversible to the supplied stock calibration.
Configurator
Build your M140i tune
Choose your stage — Stage 1, Stage 2 or Stage 3 — add the options that fit your car, and send the full build to Samuel for a custom remote remap. He'll quote, schedule, and personally calibrate within 24 hours of confirmation.
Add a stage or add-on
£0
Engine guide
BMW M140i tuning, stages, hardware and what to expect from the F20 B58 Gen 1
The M140i runs the B58 Gen 1, BMW's 3.0-litre single-turbocharged inline-six in its first-generation calibration, shared with the M240i, 340i and 440i. From the factory, BMW left meaningful headroom in the M140i's tune to suit the warranty position and global fuel-quality variation; the turbo, fuelling and chassis are all capable of considerably more than the 335 bhp / 500 Nm stock figure suggests. BMW M140i tuning with Samuel starts with finding exactly where that headroom sits on your specific car, then building a map that extracts it reliably across the full operating range. The approach is identical for a BMW M140i F20 tuning project and the F21 three-door, same drivetrain, same calibration.
Stage 1
420 bhp · 600 Nm
No hardware required. The MG1CS003 / MEVD17 DME is flashed via the OBD port, boost pressure, ignition timing, fuel delivery and torque limiters all revised. On the M140i the result is 420 bhp and 600 Nm (up from 335 / 500 stock), with substantially more accessible torque through the mid-range and a noticeably sharper throttle. This is the BMW M140i chip tuning starting point and by far the most popular single modification on the F20 / F21 platform.
Every M140i tune Samuel produces is calibrated individually for the specific car, fuel grade and installed hardware, not a base map loaded and left. BMW M140i tuning done correctly accounts for the F20 chassis weight bias, the 8HP gearbox calibration and the realities of UK fuel quality; the map is reviewed against your data logs after the first flash and revised before sign-off.
Compatibility
Platform and hardware compatibility
Bootmod3 (BM3)
Full B58 Gen 1 support across the MEVD17 (early) and MG1CS003 (later) DMEs. OBD-port flashing, realtime monitoring via the BM3 app. The most widely used platform for B58 Gen 1 tuning.
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MHD
Full B58 Gen 1 support. Suitable for Stage 1, Stage 2 and Stage 2+. Strong data-logging toolset and active community support.
Read more →
MG Flasher
Full B58 Gen 1 support. Clean interface and reliable flash process. Common alternative to BM3 for owners who prefer the MG ecosystem.
Read more →
xHP Flashtool
Compatible with the ZF 8HP gearbox fitted to every B58 Gen 1 chassis. Gearbox calibration matched to the ECU map, strongly recommended once torque jumps at Stage 2 and above. Available as an add-on.
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ECU: MEVD17 DME on early production cars; MG1CS003 DME on later production. Both accessible via OBD for Stage 1, Stage 2 and Stage 2+; bench-flash only required for some Stage 3 hybrid setups.
M140i specs & stage targets
BMW M140i tuning at a glance
- Engine
- B58 Gen 1
- Body styles
- F20 5-door · F21 3-door
- Chassis codes
- F20 / F21
- Production
- 2011–2019
- Drivetrain
- Rear-wheel drive
- Gearbox
- 8-speed ZF automatic
- Stock output
- 335 bhp · 500 Nm
- Tuning ceiling
- ~1000 bhp on the right hardware
| Stage | Target |
|---|---|
| Stage 1 | 420 bhp · 600 Nm |
| Stage 2 | 450 bhp · 650 Nm |
| Stage 2+ | 480 bhp · 680 Nm |
| Stage 3, Hybrid Turbo | 550-1000 bhp depending on spec |
| Stage 3, Big Turbo Kit | 550-1000 bhp depending on spec |
FAQ
M140i tuning — frequently asked questions
M140i Stage 1 lifts the B58 Gen 1 from a stock 335 bhp · 500 Nm to 420 bhp · 600 Nm, with no hardware required. The map is flashed through the OBD port on BM3, MHD or MG Flasher and is the starting point for almost every M140i owner — broader torque and sharper throttle response from the factory hardware.
This page covers the F20 5-door and F21 3-door (F20 / F21). They share the B58 Gen 1 engine and run the same core calibration, but every M140i tune Samuel delivers is tailored to your exact car, fuel grade and installed hardware — never a base map loaded and left.
Stage 2 on the M140i targets 450 bhp · 650 Nm and needs downpipe (OPF delete if 2018+) + intake or panel filter. Everything else — turbo, fuel system, intercooler — holds within the Stage 2 figures on the B58 Gen 1.
On the right hardware spec the B58 Gen 1 in the M140i reaches around 1000 bhp. Stage 1 and Stage 2 run the standard turbo; beyond that needs a hybrid or full big-turbo conversion with supporting fuelling, and the calibration is built bespoke per car.
Remotely. Once Samuel has your build details, the calibrated M140i map is delivered to your flashing tool account (BM3, MHD or MG Flasher) within 24 hours and you flash it yourself over OBD in about 15 minutes. It's fully reversible — the original B58 Gen 1 stock file is supplied before you flash, so the car can return to factory at any time.
A factory warranty can be voided if BMW shows a tune caused a specific failure, so it's a personal call. Samuel's M140i maps are calibrated to stay within the mechanical limits of the B58 Gen 1 hardware, and because the tune is reversible to stock before any dealer visit, many owners run a tuned M140i without issue.
Keep exploring
Keep exploring M140i tuning
Other B58 Gen 1 models we tune: M240i, 340i, 440i.
Engine guide
B58 Gen 1 tuning
Every B58 Gen 1 BMW we calibrate, with the full Stage 1, 2 and 3 breakdown for the engine.
Learn moreStages
Stage 1 & Stage 2 explained
What separates Stage 1 from Stage 2 on the M140i, the real-world gains and the hardware each one needs.
Learn morePricing
How tuning is priced
How the licence, off-the-shelf maps and custom calibration are priced. We quote your exact spec, never a fixed menu.
Learn moreGuide
What is bootmod3?
New to remote flashing? A plain-English explainer on the platform and how a custom map reaches your car.
Learn more