Spool Stage 3 DIY Low-Pressure Fuel Pump – BMW B58 Gen 1

Spool Stage 3 DIY Low-Pressure Fuel Pump for BMW B58 Gen 1 adds a secondary boost-activated low-pressure pump using Spool's DIY hardware package.

• Genuine Walbro 450 secondary pump
• Billet aluminium pump holder
• Quick-connect fuel hose and fitting package
• Hardware required for the secondary-pump installation
• Selectable secondary-pump activation harness

Secondary Pump Activation: choose Hobbs switch, ReFlex plug-and-play or ReFlex flying-lead activation. All three supplier configurations are separate Shopify variants even though their selling price is identical.

Fitment: supplier/reseller documentation confirms F30/F31/F34 340i and F32/F33/F36 440i B58 Gen 1 applications. Confirm VIN before ordering where fuel-tank hardware differs.

Dispatch: Special order — allow 2–3 weeks.

Confirmed catalogue fitment

• Engine families: B58
• BMW chassis: F30, F31, F34, F32, F33, F36
• Vehicle models: 340i, 440i

Fuel-system selection and installation

Fuel-system parts must be selected around the complete combination of engine generation, fuel type, target output, existing pump and injector configuration, and the calibration strategy. A component appearing for an engine family does not mean it replaces every factory or upgraded fuel-system arrangement used on that engine.

Professional installation and calibration are recommended where the product changes fuel pressure, pump control, injector flow, ethanol-content input or port-injection operation. Confirm wiring, plumbing, electrical load, controller requirements and compatible supporting hardware before ordering.

Before ordering

Select your exact BMW through MLAB My Garage and review the product options, included parts and installation requirements. Where a vehicle has been modified from its original engine, transmission or fuel-system specification, contact MLAB with the VIN and current hardware list so the combination can be checked before supply.

MLAB support

MLAB by Boost and Tune can assist with product selection, workshop installation and dyno calibration for supported BMW applications in Melbourne. Product availability and lead time should be confirmed when ordering supplier-built or special-order components.