Spool FX-350 Upgraded High Pressure Pump [Gen 1 B58]

Spool Performance is proud to introduce the FX350 High-Pressure Fuel Pump, a core upgrade in our fuel system lineup engineered for high-output BMW B58 applications. The FX350 builds on our proven pump architecture to deliver a meaningful increase in fuel delivery across the entire operating range, making it ideal for ethanol blends and larger turbo setups.

Paired with our IFX Gen 1 DI injectors, the FX350 enables significantly higher direct-injection fueling capability, opening the door to DI-focused high-horsepower builds on the BMW B58 platform while maintaining OEM-level integration and reliability.

What is the FX350?

The FX350 is a high-output, upgraded high-pressure fuel pump designed for enthusiasts pushing beyond the limits of the factory fuel system. It offers a substantial increase in flow over stock, allowing for higher ethanol content, increased boost, and improved fueling stability on upgraded turbo setups.

The pump is fully E85 compatible and 100% plug-and-play, requiring no cutting, splicing, or permanent modifications. Installation is straightforward and OEM-style, making it an ideal solution for performance builds that demand more fueling without unnecessary complexity.

Are tune changes required?

Yes. The upgraded pump does require calibration changes. These changes must be applied before starting the vehicle with the FX350 installed to prevent potential damage and avoid voiding the warranty.

Spool Performance can provide calibration guidance to your existing tuner or help connect you with experienced tuners familiar with our high-pressure fuel pumps. While Spool Performance is strictly a hardware manufacturer and does not provide custom tuning, we are happy to support your tuner with any technical questions related to the pump.

Low-Pressure Fuel Pump Requirements

Proper low-pressure fueling is critical for the correct operation and long-term durability of high-pressure pumps and DI injectors. The high-pressure pump relies on fuel for lubrication through controlled internal leakage. Insufficient low-side supply can result in piston and bore damage.

Damage caused by low-pressure fuel starvation is detectable and will result in voided warranty claims. When planning your build, ensure the low-pressure fuel system is appropriately upgraded to support the FX350 and your overall power goals.