Spool FX-350 Upgraded HPFP Kit [M133]

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Our warehouse is located in Nokia, Finland.

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The delivery time for products in stock is 1-5 business days. We ship worldwide.

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Terms for product returns:

• You must return the ordered products within 14 days of receiving
• The products must be unused and without damages
• Commission fee for handling returns is 21,90€
• For product returns, the customer is in charge of the return costs. Only door to door service (Express)
• Shipping costs are not refunded

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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 M133

The Spool Performance FX-350 is the next-generation High-Pressure Fuel Pump (HPFP) upgrade for Mercedes-AMG M133 engines. This model surpasses the previous FX-200 version in performance and efficiency, offering significantly higher pressure and better fuel utilization in high-power configurations.

What is the FX-350?

The FX-350 is an advanced HPFP designed to operate at significantly higher pressures than previous solutions.

• Operating pressure up to 35 MPa / 350 bar
• Up to +90% more flow compared to stock
• Approximately +40% more fuel through the injectors before injection limits are reached
• 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 M133 engine's stock HPFP is a significant limitation for tuning:

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

FX-350:

• Elevates the fuel system capacity to a new level
• Enables larger turbochargers
• Supports demanding tuning configurations

Package contents

• 1 x FX-350 high-pressure fuel pump
• Updated 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 the pump and injectors from contaminants
• Optimized for the Mercedes platform

Spool Ethanol Content Monitor (optional)

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

Software Requirements

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

Spool:

• Provides the necessary information to the tuner
• Assists 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 cause damage to the pump and injectors
• HPFP lubrication is based on fuel flow
• Lack of fuel can lead to wear and failure

Recommendation: ensure adequate low-pressure side upgrade