Tuning · BMW 330i (G20 / G21)
330i
B48
The B48 in everyday saloon form. Hand-calibrated from Stage 1 through to a hybrid-turbo build. The B48 is sharper than its reputation when calibrated correctly.
Engine
B48
Stock
255 bhp · 420 Nm
Stage 3 ceiling
255 bhp
BMW 330i tuning
The BMW 330i (G20 / G21, 2019–present) runs the B48 2.0L turbocharged inline-four and leaves the factory at 255 bhp · 420 Nm, Rear-wheel drive, 8-speed ZF automatic. Samuel tunes the G20 Saloon and G21 Touring 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. 330i Stage 1 alone takes it from 255 bhp · 420 Nm to 310 bhp · 520 Nm on the standard turbo, flashed over OBD on BM3, MHD or MG Flasher.
Add the Stage 2 hardware and the 330i targets 340 bhp · 550 Nm; from there the B48 stretches to around 500 bhp on a hybrid or big-turbo build with supporting fuelling. Whichever stage suits the 330i, the file is delivered within 24 hours and is fully reversible to the supplied stock calibration.
Configurator
Build your 330i 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 330i tuning, stages, hardware and what to expect from the G20 B48
The G20 330i runs the higher-output B48, same block, head and turbo as the 320i, with BMW's standard 255 bhp / 420 Nm software calibration and the full injector spec. BMW 330i tuning with Samuel targets the stock turbo's real capability, which sits comfortably above the factory figure. The hardware ceiling is identical between the 330i, 430i and 530i, only the chassis weight and gearbox calibration vary slightly. BMW 330i G20 tuning (saloon) and BMW 330i G21 Touring tuning use the same map.
Stage 1
310 bhp · 520 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. BMW 330i Stage 1 unlocks 310 bhp / 520 Nm from the OEM hardware (up from 255 / 420 stock), with a noticeably broader torque curve and sharper throttle response. The BMW 330i chip tuning starting point for almost every owner.
Every 330i tune Samuel produces is calibrated individually for the specific car, fuel grade and installed hardware, not a base map loaded and left. BMW 330i tuning done correctly accounts for the G20 chassis behaviour, the 8HP gearbox calibration and 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 B48 support across every chassis in the family (320i, 330i, 420i, 430i, 530i, Z4 sDrive20i). OBD-port flashing on the MEVD17 (early) and MG1CS003 (later) DMEs. Realtime monitoring via the BM3 app, the most widely used platform for B48 tuning.
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MHD
Full B48 support. Suitable for Stage 1 and Stage 2 across the family. Strong data-logging toolset for verifying lambda, ignition correction and intake temperatures after each flash.
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MG Flasher
Full B48 support. Clean interface and reliable flash process on the MG1CS003 DME, a common choice for owners who prefer the MG ecosystem.
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xHP Flashtool
Compatible with the ZF 8HP gearbox fitted to every modern B48 chassis (G20 / G22 / G30 / G29). Available as an add-on, strongly recommended at Stage 2 where torque jumps significantly for a 2.0-litre four. Manual-gearbox cars do not need xHP.
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ECU: MEVD17 / MG1CS003 DME across B48 production. Accessible via the OBD port, no bench flash required for Stage 1 or Stage 2.
330i specs & stage targets
BMW 330i tuning at a glance
- Engine
- B48 · 2.0L turbocharged inline-four
- Body styles
- G20 Saloon · G21 Touring
- Chassis codes
- G20 / G21
- Production
- 2019–present
- Drivetrain
- Rear-wheel drive
- Gearbox
- 8-speed ZF automatic
- Stock output
- 255 bhp · 420 Nm
- Tuning ceiling
- ~500 bhp on the right hardware
| Stage | Target |
|---|---|
| Stage 1 | 310 bhp · 520 Nm |
| Stage 2 | 340 bhp · 550 Nm |
| Stage 3, Hybrid Turbo | Up to 500 bhp depending on spec |
| Stage 3, Big Turbo Kit | Up to 500 bhp depending on spec |
FAQ
330i tuning — frequently asked questions
330i Stage 1 lifts the B48 from a stock 255 bhp · 420 Nm to 310 bhp · 520 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 330i owner — broader torque and sharper throttle response from the factory hardware.
This page covers the G20 Saloon and G21 Touring (G20 / G21). They share the B48 2.0L turbocharged inline-four and run the same core calibration, but every 330i 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 330i targets 340 bhp · 550 Nm and needs downpipe + intake. Everything else — turbo, fuel system, intercooler — holds within the Stage 2 figures on the B48.
On the right hardware spec the B48 in the 330i reaches around 500 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 330i 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 B48 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 330i maps are calibrated to stay within the mechanical limits of the B48 hardware, and because the tune is reversible to stock before any dealer visit, many owners run a tuned 330i without issue.
Keep exploring
Keep exploring 330i tuning
Other B48 models we tune: G20 320i, 330e, G22 420i, 430i, 530e, 530i.
Engine guide
B48 tuning
Every B48 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 330i, 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