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Fuel-It

Fuel-It BMW N55 F-Series Multi-Port Injection (MPI/PI) / Auxiliary Fuel Rail Kit - M2 M135i M235i 335i 435i - E85 Flex Fuel Conversion, Secondary Injectors, Manifold Spacer - Bosch 52lb (550cc) Injectors

Fuel-It BMW N55 F-Series Multi-Port Injection (MPI/PI) / Auxiliary Fuel Rail Kit - M2 M135i M235i 335i 435i - E85 Flex Fuel Conversion, Secondary Injectors, Manifold Spacer - Bosch 52lb (550cc) Injectors

£1,380.05
£0.00 £1,380.05
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Port Injection Package
Port Injection Controller
Return Kit (With FPR) & Injectors

Heads-up on cancellations & returns: if you cancel an order or return an item, you won't get back 100% of what you paid. We apply a 10% restocking fee, the outbound shipping is non-refundable, and we have to pass on Shopify / PayPal payment processing fees; these aren't returned to us when we refund you. International orders also lose on exchange-rate spread in both directions. If the original packaging is damaged or missing, a reboxing charge applies. For international orders specifically, if you refuse to pay our shipping invoice or supply a prepaid label after placing the order, the same deductions apply. We're upfront about this — please be sure of your purchase before ordering.

BMW N55 F-Series Multi-Port Fuel Upgrade with Bosch 52 lb Injectors

Take your N55-powered M2, M135i, M235i, 335i or 435i to the next level with a proven auxiliary injection solution that keeps pace with high boost, ethanol blends and serious tuning. This bolt-on MPI rail and spacer plate adds precise supplementary fuelling alongside the factory direct injection system, giving your build the headroom it needs for flex fuel and strong, repeatable performance on road or track.

We run this setup on our own N55 cars and customer projects. Feedback is consistently excellent: smoother power delivery, stable AFRs, tidy fuel trims and easy calibration. If you are pushing the limits of the stock high-pressure system, this is the clean, reversible way to add capacity with OEM-plus fit and finish.

Key reasons enthusiasts choose this auxiliary fuel rail

  • Confidently run high ethanol content, including full E85, on stock or upgraded turbochargers
  • Adds secondary injectors that deliver extra fuel under load to overcome factory pump limitations
  • Neat, no-cut install with a manifold spacer that sits between the intake and cylinder head
  • Includes flow-matched Bosch 52 lb injectors for consistent cylinder-to-cylinder delivery
  • Black anodised spacer plate and fuel rail for a discreet, OEM-style appearance
  • Dual supply ports for flexible plumbing in the factory location, plus optional return port support
  • Multiple package levels available, including options with integrated ethanol content sensing and Bluetooth analyser

What this multi-port setup does

This system adds a secondary fuel rail and injectors upstream of the intake valves, supplementing the original direct-injection hardware. The result is increased fuelling capacity for ethanol blends, higher boost targets and bigger airflow, while preserving drivability and reliability. It is a straightforward, fully reversible upgrade designed specifically for the N55 in F-Series models.

Choose your package

Basic

Note: no fuel lines are included with the Basic package.

  • Custom black anodised intake manifold spacer
  • Matching black anodised auxiliary fuel rail
  • Black anodised aluminium and stainless fasteners
  • Dual feed port for stock-location routing
  • Optional return port compatibility for builds with an upgraded regulator
  • Six flow-matched Bosch 52 lb injectors
  • Extended-length studs and mounting hardware
  • BMW OEM gaskets

Bronze

  • Everything in Basic
  • Essential connection kit:
    • Two custom fittings to retain the factory feed at the high-pressure pump and engine bay supply
    • -6AN 3/8 inch upgraded fuel hose
    • High-flow Y adapter
    • 90-degree elbow for a tidy rail connection

Silver

  • Everything in Basic
  • Essential connection kit
  • Full replacement upgraded feed line that replaces the stock hard line

Gold

  • Everything in Silver
  • Integrated ethanol sensor for accurate E content monitoring when used with an analyser

Platinum

  • Everything in Silver
  • Integrated ethanol sensor
  • Bluetooth and JB4-compatible ethanol analyser with 0 to 5 volt output
    • Bluetooth requires a separately purchased iPhone or Android app

Compatibility and verification

Designed for BMW N55 F-Series M2, M135i, M235i, 335i and 435i. For a perfect match, we run a compatibility check prior to dispatch. Enter your UK registration or the last 7 digits of your VIN at checkout and our team will confirm before shipping.

Installation and fitting

Suitable for experienced home installers or professional workshops. For a hassle-free, price-competitive install, book with MJ Modifications in Warwickshire. Request a fitting quote at info@mjmodifications.co.uk.

Shipping and warranty

  • Built to order - please allow 2 business days for dispatch
  • For off-road use only
  • Manufactured by Fuel-It
  • One-year manufacturer warranty

Part number

F-N55-PI-BA-BA-550

Ethanol sensor note

Ethanol percentage is calculated by measuring the absence of petrol content. If your fuel is contaminated, the displayed reading may appear higher than the true ethanol level.

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