This bolt-on, integrated performance upgrade simultaneously solves the two most significant bottlenecks in the EJ-series intake system: air restriction and fuel supply. 

This Dual Fuel Rail Tumbler Delete Kit, CNC machined from billet aluminium, replaces the restrictive factory assembly with precision-machined billet components, providing maximum airflow and guaranteed fuel delivery for high-boost applications. 

Billet Tumbler Delete - The factory Tumble Generator Valves (TGV, often referred to as tumblers) use butterfly valves in the intake runners that create severe restriction, especially at mid to high RPMs. Our Billet Tumbler Delete Kit eliminates this bottleneck entirely:

• Unrestricted Performance: CNC machined from Billet Aluminum to create a high-flow, smooth internal runner.
• Significant Power Gains: By smoothing the path of air into the cylinder heads, you remove a major choke point, resulting in measurable increases in horsepower and torque across the entire rev range.
• Precision Design: Features a smooth, radiused inlet and outlet profile, ensuring maximum laminar flow into the cylinder head ports.

Dual Fuel Rails - For serious power builders utilising upgraded turbos, injectors, and E85 or race fuels, the factory single-feed fuel system is inadequate. Our integrated Dual Fuel Rails solve fueling inconsistencies under high load:

• Consistent Fuel Pressure: The dual-rail design supports larger injectors and provides a reliable, uninterrupted flow of fuel, preventing fuel starvation issues common in highly tuned applications.
• High-Volume Ready: Essential for high-horsepower builds, ensuring your engine receives the precise volume of fuel required when running increased boost or alternative fuels (E85).
• Integrated Design: Seamlessly engineered into the TGV Delete assembly, reducing complexity and potential failure points compared to separate rail and spacer kits.

Vehicle Compatibility

• Subaru WRX & STI (EJ20/EJ25) 2001–2007 (GD Chassis)
• Subaru STI (EJ25) 2008–2021 (GR/GV/VA Chassis)