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Home / ECU Remapping / BMW 125i
N20 Engine

BMW 125i

F20/F21

The N20-powered 125i offers solid four-cylinder turbo performance. ECU remapping unlocks meaningful gains in both power and throttle response.

218 Stock BHP
280 Stage 1 BHP
330+ Stage 3 Ceiling
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BMW 125i F20/F21
Performance Stages

N20 Tuning Stages

All power figures are average estimates based on typical results. Actual gains depend on vehicle condition, fuel quality and supporting modifications.

01

Stage 1

260-280 bhp

Software only. No hardware changes required. Custom ECU calibration on fully standard engine.

  • Custom map written in-house
  • No additional parts needed
  • Fully reversible
02

Stage 2

290-310 bhp

Calibrated for bolt-on modifications. Downpipe, intake and supporting hardware.

  • Requires supporting hardware
  • Mapped to your specific mods
  • Data-logged and validated
03

Stage 3

330+ bhp

Full custom calibration for serious builds. Hybrid turbos, uprated fuelling and bespoke mapping.

  • Hybrid or upgraded turbo
  • Uprated fuel system
  • Bespoke build calibration

Ready to Tune Your 125i?

Get in touch to discuss your build. Every map is written in-house and tailored to your car.

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