Spool Performance BMW N55 FX-170 Upgraded High Pressure Fuel Pump
What is the FX-170?
The FX170 is an upgraded BMW n55 high pressure fuel pump for the 35i Single Turbo BMW motors. The pump features a bigger bore size than stock that translates into roughly 50% more flow when compared to stock. The pump is completely E85 compatible and fully plug and play with no cutting or splicing of any kind required. The added flow will let you run much higher ethanol concentrations and also allow fueling for bigger turbos.
Why do you need it
The stock HPFP on N55 motor is severely limited in capacity when trying to tune and raise the output of the motor. The FX-150 adds 50% more flow to the equation, raising the fueling limits on the platform and helping you run bigger turbos and/or higher ethanol concentration blends.
Tune changes
The upgraded pumps do require calibration changes. It is important to apply these changes prior to starting the car with pump installed to avoid any possible damage and void of warranty.
Spool Performance can provide calibration details to your existing tuner and/or help you connect with established tuners who are experienced with these pumps. Custom tuning is required to get maximum output out of the upgraded pump setup for your specific vehicle setup and ambient conditions. Spool Performance is a hardware manufacturer and does not provide custom tunes, but can assist with questions your tuner may have.
Low Pressure Fuel Pump Upgrade:
Proper low pressure fueling is extremely important for proper functioning and durability of the high pressure pumps and injectors in a DI system. Inadequate low pressure fueling can cause damage to the pump piston and bore as they are lubricated by controlled leakage of fuel. Resulting damage from low pressure starvation is detectable and would be cause for voided warranties. Please make sure you plan out your fuel system build with proper low pressure upgrades when necessary.
Please Note: For customers with E9X chassis 335i or E8X 135i made before 03/2012, you will need the Spool Performance BMW N54 N55 E90 E91 E92 E93 335i Helix HPFP Overdrive Unit.