Spool Performance Stage 3 LPFP/Low Pressure Fuel Pump DIY Kit for BMW B58 F-Series - Boost-Activated Walbro 450 In-Tank Auxiliary Lift Pump | M140i M240i 340i 440i xDrive (F20 F21 F22 F23 F30 F31 F32 F33 F36)

Stage 3 In-Tank Lift Pump DIY Kit for BMW B58 F-Series - Spool Performance Walbro 450 Boost-Referenced Auxiliary Pump

Push your B58-powered BMW further with a proven low-side fuelling upgrade that keeps petrol delivery rock solid under load. This Spool Performance Stage 3 in-tank auxiliary pump package adds a boost-referenced secondary pump to support higher boost and tuning on M140i, M240i, 340i and 440i models. Built around a genuine Walbro 450 unit with billet aluminium hardware and OE-style quick connectors, it delivers big capability with tidy, reliable fitment.

We run this kit in-house and have installed it for many customers. Feedback is consistently excellent. It fixes low-side pressure drop on mapped B58 cars, gives confidence on spirited road driving and keeps the fuel system happy as power goals increase. If you are outgrowing the factory lift pump, this is the dependable solution.

Why enthusiasts pick this setup

• Boost-referenced secondary in-tank pump that comes online under load for stable low-side pressure
• Genuine Walbro 450 core with Spool Performance components for durability and flow
• Billet aluminium pump cradle for a secure, OE-like installation
• Clean plumbing with quick-connect fittings and included activation harness
• Comparable output to the Spool PnP option at a keener price point
• Ideal for tuned B58 cars targeting stronger fuelling headroom

What you get in the box

• Walbro 450 pump modified with two-way quick-connect fitting
• Billet aluminium pump holder
• Filter-side quick-connect nylon hose
• Pump-side quick-connect
• Spare nylon hose
• Crimp clamps x2
• Screw-on clamps x2
• Activation harness
• Boost-activated switch
• Boost reference adapter
• Hardware pack

Fitment - BMW B58 F-Series applications

Designed for 1 Series, 2 Series, 3 Series and 4 Series models with the B58 engine, including xDrive variants:

1 Series

• F20 LCI - 09/2015 to 06/2019 - M140i and M140ix
• F21 LCI - 09/2015 to 06/2019 - M140i and M140ix

2 Series

• F22 - 09/2015 to 06/2017 - M240i and M240ix
• F22 LCI - 09/2016 to 12/2019 - M240i and M240ix
• F23 - 09/2015 to 06/2017 - M240i and M240ix
• F23 LCI - 10/2016 to 12/2019 - M240i and M240ix

3 Series

• F30 LCI - 10/2014 to 10/2018 - 340i and 340ix
• F31 LCI - 10/2014 to 06/2019 - 340i and 340ix
• F34 GT LCI - 10/2014 to 2019 - 340i and 340ix

4 Series

• F32 - 2013 to 02/2017 - 440i and 440ix
• F32 LCI - 05/2016 to 12/2019 - 440i and 440ix
• F33 - 03/2015 to 02/2017 - 440i and 440ix
• F33 LCI - 05/2016 to 12/2019 - 440i and 440ix
• F36 Gran Coupe - 03/2015 to 02/2017 - 440i and 440ix
• F36 Gran Coupe LCI - 05/2016 to 12/2019 - 440i and 440ix

Performance-focused highlights

• Stabilises low-side supply for mapped B58 engines under higher boost
• DIY-friendly kit with clear guidance and OE-style connectors
• High value upgrade that retains strong flow capability

Pre-dispatch compatibility check

We will verify fitment before shipping. Please provide your UK registration or the last 7 of your VIN at checkout.

Installation

This DIY package assembles neatly using the supplied fittings and harness. Prefer professional fitting or a same-day turnaround in the Midlands? Book with MJ Modifications in Warwickshire. Request a quote at info@mjmodifications.co.uk.

Part number

SP-BMB58-FP-DY

Brand

Spool Performance

Helpful search terms

M140i fuel system upgrade, M240i lift pump kit, 340i auxiliary fuel pump, 440i in-tank pump upgrade, B58 low-side fuelling solution, Walbro 450 B58 kit, boost-referenced fuel pump BMW, F20 F21 F22 F23 F30 F31 F32 F33 F36 fuel pump kit, B58 petrol pump upgrade, BMW 3.0 turbo fuel supply upgrade.