Spool FX-170 HPFP Upgrade | BMW S55
The Spool Performance FX-170 is a high-pressure fuel pump (HPFP) performance upgrade for BMW S55 engines. This solution is designed to significantly increase the fuel system's capacity, enabling higher power output and ethanol blends.
What is the FX-170?
The FX-170 is an upgraded HPFP with a larger cylinder bore than the stock pump. This allows for approximately +50% greater fuel flow.
- Approx. +50% flow compared to stock
- Up to approx. +25% higher operating pressure
- Full E85 compatibility
- Plug & Play installation without modifications
Benefits of higher pressure:
- Improves injector flow with the same open time
- Enables more efficient combustion
- Supports higher power levels
Why is an upgrade necessary?
The S55 engine's stock HPFP is a limiting factor in tuning:
- Insufficient fuel delivery for high power
- Limited use of ethanol blends
FX-170:
- Significantly increases fuel system capacity
- Enables larger turbochargers
- Expands the platform's tuning potential
Package contents
- 2 x FX-170 high-pressure fuel pumps
- Upgraded fuel lines + installation hardware
- Bosch 10 micron high flow fuel filter
- Ethanol content monitoring system with mobile app
Spool 10-micron filter
- Excellent filtration efficiency without significant pressure drop
- Protects pumps and injectors from contaminants
- Designed for the S55 platform
Spool Ethanol Content Monitor
- Real-time monitoring of ethanol content and fuel temperature
- BLE 4.0 connection to mobile application
- Enables precise mixture ratio control
- Full E85 compatibility for fuel lines
Software requirements
- Requires software modifications before use
- Calibration must be performed before using the pump
Spool:
- Provides necessary information to the tuner
- Helps in finding an experienced tuner if needed
Note: Spool does not offer ready-made custom tunes
Important note: LPFP
The low-pressure fuel system is critical:
- Insufficient supply can damage pumps and injectors
- HPFP lubrication relies on fuel flow
- Lack of fuel can lead to wear and failure
Recommendation: ensure sufficient low-pressure side upgrade