Product Description
BMW S55 FX-170 Upgraded High Pressure Fuel Pump - Spool Performance SP-FX-S55-AE
What is the FX-170?
The FX-170 is a high-performance upgraded high-pressure fuel pump (HPFP) designed to push the fueling limits of the S55 engine. Featuring a larger bore than the stock unit, it delivers 50% more flow, making it an ideal upgrade for high-power builds. The FX-170 is fully E85 compatible and plug-and-play, requiring no cutting or splicing for installation. Additionally, it operates at 25% higher pressure than stock, allowing injectors to deliver increased fuel volume for the same opening time.
Why Do You Need It?
The factory S55 HPFP is a significant bottleneck when tuning for higher horsepower and ethanol blends. The FX-170 eliminates this limitation, increasing fueling headroom for larger turbos, aggressive E85 mixtures, and high-boost applications. With improved flow and higher operating pressure, the FX-170 ensures your fueling system keeps up with performance demands.
What’s Included in the Kit?
- 2x FX-170 Upgraded High-Pressure Fuel Pumps
- 1x Optional Ethanol Content Monitor Kit with mobile app support
- 1x Bosch-Spec 10-Micron High-Flow Fuel Filter
- Upgraded Fuel Lines & Complete Installation Hardware
Spool 10-Micron Fuel Filter
The included 10-micron filter unit provides the best filtration available for the S55, safeguarding your fuel system from debris without any pressure drop in the low-pressure side. This ensures long-term reliability by protecting HPFPs and injectors from contamination.
Spool Ethanol Content Monitor
The Spool ECA (Ethanol Content Analyzer) Kit offers real-time monitoring of in-tank ethanol content and fuel temperature. Data is accessible through the Spool Performance mobile app, utilizing BLE 4.0 low-energy Bluetooth for seamless connectivity without interfering with other Bluetooth devices. All braided steel nylon-core fuel lines in the kit are 100% E85 compatible.
Do You Need a Tune?
Yes, calibration changes are required before starting the vehicle with the upgraded pumps installed. Spool Performance provides calibration details to your tuner and can assist in connecting you with experienced tuners. Custom tuning is necessary to optimize the setup for your specific modifications and ambient conditions.
Note: Spool Performance is a hardware manufacturer and does not provide custom tuning services but is available for support regarding tuning-related inquiries.
Low-Pressure Fuel Pump (LPFP) Upgrade – A Must-Have
A properly upgraded low-pressure fuel system is critical for the health and efficiency of high-pressure fuel pumps and injectors in direct injection (DI) systems. Insufficient LPFP supply can lead to premature wear or damage to the HPFP’s piston and bore due to improper lubrication from fuel leakage. Any damage resulting from low-pressure starvation is detectable and not covered under warranty. Ensure your fuel system is adequately upgraded to support your power goals.
Our goal at SPOOL PERFORMANCE is to offer the highest quality parts for the most affordable price without sacrificing performance. We pride ourselves on our commitment to exceeding the industry standard for customer service, performance, and product quality. Before the release of any of our products, our engineers at SPOOL PERFORMANCE make sure that our products will live up to expectations. The development of any part goes through stages of rigorous research, CAD designing, prototype development, CFD analysis, and endurance testing. Fitment, functionality, and longevity are extensively tested before any product makes it to our website for sales. During our beta testing stage, testers from all across the nation and often around the world will push our products to the limit to make sure that our products exceed customer expectations in different environmental settings and across a variety of different power levels our customers are at.
