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B58 Gen 2 Engine

BMW M340i

G20/G21

The G20 M340i is the sweet spot of the 3 Series range. The B58 Gen 2 delivers impressive gains with just a Stage 1 remap and no hardware changes.

374 Stock BHP
470 Stage 1 BHP
520+ Stage 3 Ceiling
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BMW M340i G20/G21
Performance Stages

B58 Gen 2 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

440-470 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

480-510 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

520+ 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 M340i?

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

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