Process West Double W460 Pump Anti-Surge Fuel System Subaru WRX / STI 2008-2014 | PWFS04

Product Fitment:

2008-2014 Subaru WRX

2008-2014 Subaru STI

A fully engineered fuel delivery upgrade designed to eliminate fuel starvation under high load while remaining clean, compact, and OEM-like in appearance.

Key Features

• 2.4L surge vessel capacity for stable fuel supply under sustained cornering, acceleration, and track use
• Internally mounted Walbro 460 LPH pump (single pump configuration)
• Near-zero pump noise thanks to external billet surge vessel isolation
• Built-in check valve (Walbro pump) for improved fuel control and system stability
• Complete plug-and-play wiring harness included for simplified installation
• Hidden installation design — fully concealed when viewed from the engine bay
• Upgradeable architecture — can be converted to twin pump system if fuel demand increases

System Design Overview

This system replaces the limitations of in-tank fuel pickup designs with an externally mounted anti-surge reservoir constructed from 6061 billet aluminium.

The surge tank is positioned above the transmission cross member, allowing:

• Consistent fuel pickup under high lateral G-loads
• Reduced risk of fuel starvation during track driving or aggressive street use
• Stable fuel pressure delivery even at low tank levels

Unlike in-tank “surge-style” solutions, this setup physically separates surge management from the main tank, improving reliability in sustained high-performance conditions.

Fueling Capability

The single Walbro 460 configuration is designed to support high-output builds while maintaining simplicity:

• Supports approximately up to ~550 kW at the wheels (petrol applications) depending on supporting modifications and tuning
• Ideal for most street and fast-road Subaru WRX/STI builds
• Designed for compatibility with modern fuels and tuning strategies

Installation & Configuration Notes

• Supplied as a complete single-pump system (including lines and wiring harness)
• Only minimal electrical work required (basic harness integration)
• Designed to remain out of sight in the engine bay for a clean OEM+ appearance

System Upgrade Path

This platform is engineered for scalability:

• Single pump system (this version):
  Simplified installation, supports the majority of performance builds
• Twin pump upgrade option:
  For higher fuel demand applications (typically above ~550 kW), system can be expanded to dual Walbro 460 pumps with external fuel pressure regulation and -6 AN plumbing requirements