Spool Stage 4 FX400X High-Pressure Fuel Pump – BMW B58 Gen 2

Spool Stage 4 FX400X High-Pressure Fuel Pump for BMW B58 Gen 2 is Spool's flagship high-pressure pump for high-output direct-injection builds.

• Supplier-rated for up to 350 bar / 35 MPa / 5000 psi operation
• Approximately 20% more delivery across the range than Spool's FX350
• Plug-and-play architecture with mounting hardware, pump alignment tool, low-pressure line and adapter harness
• Designed for use with upgraded B58 Gen 2 direct-injection systems

Selectable options: wireless ethanol analyzer and Spool 10-micron filter.

Important: calibration changes are required and adequate low-pressure fuel supply is critical.

Dispatch: Backorder — lead time confirmed when stock is allocated.

Confirmed catalogue fitment

• Engine families: B58
• BMW chassis: G01, G02, G05, G06, G07, G20, G21, G22, G23, G26, G29, G30, G31, G32, G42, G43
• Vehicle models: M240i, M340i, M440i, 540i, 640i, 740i, 840i, X3 M40i, X4 M40i, X5 40i, X6 40i, X7 40i, Z4 M40i

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.