N20 · 2.0 turbo four-cylinder
The N20 is BMW's 2.0-litre turbocharged four from the 328i, 428i, 528i, 228i, 125i, X3 28i and Z4 28i — the predecessor to the B48, and a genuinely worthwhile, affordable tune.
N20 vehicles
SamuelTuned covers N20 tuning and remapping across the BMW 125i (F20 / F21), BMW 228i (F22), BMW 328i (F30 / F31), BMW 428i (F32 / F33 / F36), BMW 528i (F10 / F11), BMW X3 28i (F25) and BMW Z4 28i (E89). Each one gets a custom, individually-calibrated remote ECU remap — Stage 1, Stage 2 and Stage 3. Open the configurator on your car to choose your stage, add the options that fit, and send the full build to Samuel.
F20 / F21
125i
218 bhp stock
125i Configure Tuning
F22
228i
245 bhp stock
228i Configure Tuning
F30 / F31
328i
245 bhp stock
328i Configure Tuning
F32 / F33 / F36
428i
245 bhp stock
428i Configure Tuning
F10 / F11
528i
245 bhp stock
528i Configure Tuning
F25
X3 28i
245 bhp stock
X3 28i Configure Tuning
E89
Z4 28i
245 bhp stock
Z4 28i Configure Tuning
Engine guide
The N20 is conservatively mapped from the factory and frees up a useful, daily chunk of performance with a custom Stage 1 — stronger mid-range and sharper throttle that makes a 328i or 428i feel genuinely brisk rather than merely adequate.
N20 cars are now mature and conditions vary; calibrating to your datalogs and fuel is the safe way to get the gain without leaning on a generic file. Samuel maps each car to its exact variant and supporting hardware.
Stage 1 is software only and flashed remotely. Stage 2 adds breathing hardware for more top-end. We tune the N20 on Bootmod3, MHD or MG Flasher depending on the car and DME.
Tune stages
Stage 1
Strong gain
Software only on stock hardware. Noticeably stronger mid-range.
Stage 2
Bigger top-end
Downpipe + intake where applicable.
Figures are indicative and depend on the exact model, fuel and supporting hardware. Every tune is calibrated individually — open the configurator for your car for the precise build and price.
FAQ
Yes — the N20 is meaningfully detuned from the factory, so a custom Stage 1 delivers a useful, daily-usable gain in mid-range and response at a very accessible price.
Bootmod3, MHD and MG Flasher cover the N20 depending on the model and DME. Samuel confirms the right one from your VIN.
Yes. The N20 is calibrated remotely from your datalogs and flashed at home — no workshop visit needed.
No — Stage 1 is software only. Hardware only comes in at Stage 2 for the bigger top-end gains.
Keep exploring
Platform
Our primary flash platform for N20 builds: app-driven, OTA custom map delivery.
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