Spool FX-350 Upgraded HPFP Kit [M276]

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• You must return the ordered products within 14 days of receiving
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• Commission fee for handling returns is 21,90€
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Return address: QT Parts, Vasarakatu 8B, 37150 Nokia, Finland.

Pre order / made-to-order products

If the product you have ordered is a pre order or made-to-order item, it is not subject to the 14-day right of withdrawal or return under consumer protection laws, as the product is manufactured or sourced specifically based on the customer’s individual order.

If you wish to cancel your order before receiving the product, we will refund 50% of the total order amount.

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.

In the event of such a defect, the standard liability for defects as provided by consumer protection legislation shall apply.

Spool FX-350 HPFP Kit | AMG M276

The Spool Performance FX-350 is a high-performance high-pressure fuel pump (HPFP) upgrade for Mercedes-Benz M276 engines. This model represents the next evolutionary step from the FX-200, offering significantly higher operating pressure and clearly improved fuel capacity for demanding tuning setups.

What is the FX-350?

The FX-350 is an advanced HPFP designed to produce significantly more pressure and flow than previous models.

• Operating pressure up to 35 MPa / 350 bar
• Up to +90% more flow compared to stock
• Approx. +40% more fuel through the 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

Why is an upgrade necessary?

The M276 engine's stock HPFP is a significant limitation for tuning:

• Insufficient fuel delivery for high power levels
• Limited use of ethanol blends

The FX-350:

• Elevates the fuel system capacity to a new level
• Allows for larger turbochargers
• Supports demanding performance configurations

Package Contents

• 1 x FX-350 High-Pressure Fuel Pump
• Upgraded fuel lines + installation hardware
• Bosch 10 micron high flow fuel filter
• Ethanol content monitoring system with mobile application

Spool 10-micron filter

• Top-tier filtration without significant pressure drop
• Protects pump and injectors from contaminants
• Optimized for the M276 platform

Spool Ethanol Content Monitor

• Real-time ethanol content and fuel temperature monitoring
• BLE 4.0 connection to mobile application
• Enables precise fuel mixture control
• PTFE core, stainless steel braided E85-compatible fuel lines

Software Requirements

• Requires software modifications before commissioning
• Calibration must be performed before using the pump

Spool:

• Provides necessary calibration data to the tuner
• Assists in finding an experienced tuner if needed

Note: Spool does not offer ready-made custom tunes

Important consideration: LPFP

The low-pressure fuel system is critical:

• Insufficient supply can damage 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