Spool Performance Audi RSQ8 FX-350 Upgraded High Pressure Fuel Pump System - SP-EA825RSQ8-FX350

The Spool Performance FX-350 Upgraded High-Pressure Fuel Pump System is a high-output fueling solution developed specifically for the Audi RS Q8 equipped with the EA825 engine. This system addresses the factory high-pressure fuel pump limitation that becomes evident when increasing power, boost, or ethanol content on performance-oriented RS Q8 builds.

The system features two Spool Performance FX-350 mechanical high-pressure fuel pumps, each engineered with a significantly larger internal bore than the OEM pumps. This design delivers approximately 90% more fuel flow compared to stock, allowing the engine to safely support higher horsepower levels, increased boost pressure, larger turbocharger configurations, and high ethanol blends up to full E85.

The FX-350 is capable of operating at fuel pressures of up to 350 bar, which improves injector efficiency while reducing injection duration. Higher operating pressure enhances fuel atomization and combustion stability, especially under sustained high-load conditions. Compared to lower-output fuel pump upgrades, the FX-350 provides a substantial increase in usable fuel delivery for demanding performance applications.

This Spool Performance system is fully plug-and-play, requiring no cutting, splicing, or permanent vehicle modifications. All components are designed for direct installation and long-term reliability. The FX-350 pumps are fully E85 compatible and built to withstand aggressive tuning and high-performance driving conditions.

Included in the system is a Bosch-spec 10-micron high-flow fuel filter, engineered to protect both the high-pressure fuel pumps and fuel injectors from contaminants without introducing pressure drop on the low-pressure side of the fuel system. An optional Spool Performance Ethanol Content Monitor is available, providing real-time ethanol percentage and fuel temperature data through a mobile application to support accurate tuning and fuel quality monitoring.

The Spool Performance FX-350 system is intended for serious performance applications. Custom ECU calibration is mandatory, and sufficient low-pressure fuel system capacity is required to ensure proper operation and prevent component damage.

Fitment

Vehicle Compatibility:

• Audi RS Q8

Model Years:

• 2020–2024

Engine:

• EA825 4.0T Twin-Turbo V8

Drivetrain:

• Quattro AWD

Notes:

• Designed exclusively for Audi RS Q8 with EA825 engine
• Not compatible with non-RS Q8 models or other Audi platforms
• ECU tuning is required prior to operation
• Proper low-pressure fuel system support is mandatory

What’s Included

• 2 x Spool Performance FX-350 upgraded high-pressure fuel pumps
• 1 x Bosch-spec 10-micron high-flow fuel filter
• Upgraded fuel lines
• Required installation hardware
• Optional Spool Performance Ethanol Content Monitor kit with mobile app support

Why Upgrade the High-Pressure Fuel Pump

The factory high-pressure fuel pump on the Audi RS Q8 becomes a performance bottleneck when power output, boost pressure, or ethanol concentration is increased. The Spool Performance FX-350 eliminates this restriction by delivering significantly higher fuel volume and pressure, ensuring consistent fueling under extreme performance demands.

This upgrade is ideal for:

• High-horsepower RS Q8 builds
• Larger turbocharger configurations
• High ethanol or full E85 fueling
• Reduced injector duty cycle at elevated power levels

Tuning and Fuel System Requirements

• ECU calibration changes are required before operation
• Improper tuning can result in engine or fuel system damage
• Low-pressure fuel supply must meet increased fuel demand
• Inadequate low-pressure fueling can damage the high-pressure pumps and void warranties

Note: 'New' merchandise may be returned for exchange or refund within 15 days from the date of shipment. 'New' merchandise must be unused and free from installation or mounting damage. Installation or modification of parts waives your right to returns, refunds, or exchanges.