BMW N54/N55 Dual In-Tank Low Side Fuel Pump Hanger - Fuel-It Stage 4 Twin Walbro 450/525 LPFP Kit, -6AN Lines + 6 Micron Filter, E85/Flex Fuel - 1M 135i 335i (E82 E90 E92 E93 X1 E84) - HPFP/Port Injection Feed, Return-Style Ready

Stage 4 Twin In-Tank Fuel Supply Upgrade for BMW E Chassis N54 and N55 – E85 Ready with -6AN Lines

Chasing big power on your N54 or N55 and sick of low side pressure dropping under boost? This Stage 4 twin in-tank fuel supply from Fuel-It is the proven fix for hard-running 1M, 135i and 335i builds that need stable delivery on petrol or ethanol blends. It fits inside the factory bucket, keeps the OE jet pumps working as intended and massively increases volume for consistent rail pressure when you lean on it.

We run this hardware on our own cars and customer vehicles, and it is rock solid. Expect up to three times the flow of the standard lift pump, quiet operation, excellent drivability and reliable fuelling for hybrid turbos, single-turbo conversions, track days and dragstrip use.

Why enthusiasts choose this kit

• Serious headroom for N54 and N55 builds that push beyond 600 wheel horsepower targets
• Twin Walbro turbine pumps inside the OE-style hanger for stock-like fitment and fuel pickup
• Retains jet pump transfer function while bypassing restrictive factory plumbing for higher sustained pressure
• Boost-referenced secondary activation for steady low-side pressure under heavy load
• Ethanol-safe throughout – ideal for E85, flex-fuel and mixed blends
• Complete -6AN line set and a 6 micron ethanol-compatible filter to feed both HPFP and port injection
• Individually flow tested before dispatch for peace of mind

What you get

• Preassembled replacement in-tank bucket with twin pumps and OE-style pick-up
• Two new Walbro 450 ethanol-compatible pumps – part number F90000274
  • Optional pump upgrade to Walbro 525 – part number F90000285
• Two fresh Walbro strainers
• Custom fittings designed to optimise jet pump function and output
• Spare vent tube clip
• Secondary pump wiring harness
  • This harness must be installed to utilise the second pump
• Complete -6AN hose kit to the 6 micron ethanol-safe filter, HPFP feed and port injection rail
• 6 micron filter assembly compatible with ethanol fuels
• Flow test results prior to shipping

Important: A return-style system with an external fuel pressure regulator and a port injection kit are required to run the secondary pump.

Additional items you will need for the twin-pump configuration

• Return conversion kit
• Port injection hardware

Recommended add-ons

• Lock ring tool for safe pump module removal
• Hobbs switch for boost-referenced secondary pump control
• Ethanol content analyser and sensor
  • Options: Bluetooth only, Bluetooth with JB4 0-5 V integration, or Bluetooth with 50-150 Hz raw signal

Vehicle coverage – BMW E chassis turbo petrol models

Designed for all E chassis cars equipped with the N54 or N55 engine including 1M Coupe, 135i and 335i, plus applicable X1 E84 models.

• E82 Coupe and E88 Convertible
• E90 and E90 LCI Saloon
• E91 and E91 LCI Touring
• E92 and E92 LCI Coupe
• E93 and E93 LCI Convertible
• X1 E84

Fitment check before we ship

Enter your UK registration or the last 7 of your VIN at checkout and we will confirm compatibility before dispatch to make sure you receive the correct assembly for your car.

Installation and setup

Professional fitting is recommended. For expert installation, wiring and return-system setup, book with MJ Modifications in Warwickshire. Request a quote via info@mjmodifications.co.uk.

Part number

FI001

Manufacturer and warranty

Manufactured by Fuel-It with a Fuel-It limited warranty.

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