Spool FX-350 HPFP AMG GT, GTS, GTC, GTR [M178]

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Pre order / made-to-order products

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This condition applies to the following product categories:

• Suspension
• Engine Tuning
• Engine Parts
• Exhaust Systems
• Fueling
• Turbochargers/superchargers
• Drivetrain
• ECE-approved Downpipes

All of the above products are manufactured or sourced individually based on the customer’s order, and therefore cannot be returned after delivery, unless the product has a manufacturing or material defect.

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Spool FX-350 HPFP Kit | AMG GT / GTS / GTC / GTR (M178)

The Spool Performance FX-350 is the next generation high-pressure fuel pump (HPFP) upgrade for Mercedes-AMG M178 engines. This solution surpasses the previous FX-200 model in both pressure and overall performance, providing significantly improved fuel delivery for high-power applications.

What is the FX-350?

The FX-350 is designed to operate at significantly higher pressure than its predecessor, directly increasing fuel flow through the injectors.

• Operating pressure up to 35 MPa / 350 bar
• Up to +90% more flow compared to stock
• Approximately +40% more fuel through injectors before reaching injection limits
• Full E85 compatibility
• Plug & Play installation

Benefits of higher pressure:

• Improved fuel atomization
• More efficient and cleaner combustion
• Increased power and better efficiency
• Allows for higher power without additional injection

Why is an upgrade necessary?

The M178 engine's stock HPFP significantly limits tuning potential:

• Fuel capacity is insufficient for high power levels
• Use of ethanol blends is limited

The FX-350:

• Elevates the fuel system capacity to a new level
• Allows for larger turbochargers
• Supports more aggressive tuning configurations

Package contents

• 2 x FX-350 high-pressure fuel pumps
• Upgraded fuel lines + installation hardware
• Bosch 10 micron high flow fuel filter
• Ethanol content monitoring system (optional, with mobile app)

Spool 10-micron filter

• Excellent filtration efficiency without pressure drop
• Protects pumps and injectors from contaminants
• Designed for the Mercedes platform

Spool Ethanol Content Monitor (optional)

• Real-time ethanol content and fuel temperature monitoring
• BLE 4.0 connection to mobile app
• Allows for precise mixture ratio control
• PTFE-lined, braided stainless steel E85-compatible fuel lines

Software requirements

• Requires software modifications before commissioning
• Calibration is essential for safe and optimal operation

Spool:

• Provides necessary calibration data to the tuner
• Helps find 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 cause damage to the pump and injectors
• HPFP lubrication relies on fuel flow
• Lack of fuel can lead to wear and failure

Recommendation: ensure adequate low-pressure side upgrade