BMW B58 Gen 1 Upgraded Direct Fuel Injectors – Xtreme-DI XDI +75% High-Flow Bosch DI Injector Set | M140i M240i 340i 440i 540i 740i X3/X4 M40i | 250 Bar Plug-and-Play Performance Injector Upgrade UK

Uprated Direct Injection Injectors for BMW B58 Gen 1

Unlock reliable fuelling headroom for your turbocharged BMW straight-six with this Bosch-based XDI uprated injector package. Designed specifically for the first-generation B58 engine, these premium petrol direct injection units deliver roughly 75 per cent more flow than the factory items while keeping OEM-like manners at idle, cruise and full throttle. Perfect for cars targeting higher power with rock-solid drivability at up to 250 bar fuel rail pressure.

We have installed these injectors on our own projects and many customer builds at MJ Modifications. Feedback has been consistently positive for smooth running, clean cold starts and strong performance under load. If you are pushing past the stock fuelling limits, this is a proven, dependable solution that supports serious performance goals without compromising refinement.

Key reasons to choose these B58 Gen 1 injectors

• Approximately 75 per cent increase in flow compared to factory B58 injectors for significant fuelling overhead
• Tight matching within a 0.5 per cent spread to promote stable idle, cylinder balance and consistent trims
• Engineered to operate cleanly at elevated rail pressures, up to 250 bar (3600 psi)
• True plug-and-play fit with original connectors and seals, no wiring changes required
• Bosch core injectors developed and calibrated by XDI specifically for BMW B58 Gen 1 applications

Flow testing and documentation

Each set is individually tested and supplied with data sheets for transparent, repeatable results at multiple operating points:

1. 0.8 ms at 20 bar for idle character
2. 10 ms at 100 bar for static reference
3. 6 ms at 200 bar for high-load stability

Maximum rail pressure: 250 bar / 3600 psi.

Vehicle compatibility

For BMW models equipped with the B58 Gen 1 petrol engine:

• F20/F21 1 Series — M140i, M140xi
• F22/F23 2 Series — M240i, M240xi
• F30/F31/F34 3 Series — 340i, 340xi
• F32/F33/F36 4 Series — 440i, 440xi
• G30/G31 5 Series — 540i, 540xi (up to MY2019)
• G32 6 Series — 640i, 640xi (up to MY2019)
• G11/G12 7 Series — 740i, 740xi (up to MY2019)
• G01 X3 — M40i (up to MY2019)
• G02 X4 — M40i (up to MY2019)

Important: Not suitable for B58 TU engines. Please confirm your car is B58 Gen 1 before ordering.

Tuning and calibration

ECU calibration is required after installation. XDI have indicated ongoing support work for popular flashing solutions such as MHD and BM3, and ECUtek and WinOLS have been reported to function correctly. Always consult your chosen tuner to apply the correct injector data for your setup.

Professional fitting

Although these are a direct-fit upgrade, we recommend professional installation. MJ Modifications offer fitting and support in Warwickshire. Request a quote: info@mjmodifications.co.uk.

Who benefits from this upgrade

Ideal for enthusiasts running increased boost, larger turbochargers or looking for dependable fuelling at higher load on the B58 Gen 1 platform. Enjoy factory-like refinement with the flow capacity needed for meaningful power gains.

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