Unleash the full breathing potential of your Subaru EJ engine.

Ichiban Engineering’s Billet TGV Deletes replace the restrictive OEM tumble generator valve housings with fully CNC-machined, 5-axis billet aluminum units — engineered to deliver smooth, unrestricted airflow and uncompromising performance.
 
Each port was CFD-tested and refined in-house, ensuring a perfectly balanced flow path and velocity distribution between cylinders. Whether you’re chasing every horsepower on the dyno or building a reliable track car, these are designed to perform under pressure.
 
Key Features
 
🌀 CFD-Optimized Port Geometry
Designed using Computational Fluid Dynamics to minimize turbulence and pressure loss — improving cylinder balance and spool response once tuned.
⚙️ True 5-Axis Billet Construction
Machined from a single solid block of 6061-T6 aluminum for perfect port alignment and gasket surfaces — no cast cores, no porosity, and no weak spots.
💨 Increased Flow & Power Potential
Removes restrictive butterfly valves and shaft assemblies, supporting higher airflow and more stable fuel distribution under boost.
🧩 Direct Bolt-On Fitment
Engineered to fit OEM intake manifolds with precision — retaining factory alignment and injector positions for seamless installation.
🔩 Precision Sealing
CNC-finished faces and dowel-accurate alignment ensure zero boost or vacuum leaks, even in extreme boost conditions.
🎨 Custom Anodized Finishes (Exclusive to Ichiban)
Unlike most competitors who only offer raw or black finishes, we offer multiple anodizing color options — giving your engine bay a clean, premium, and fully customized look.
🛠️ Motorsport-Grade Materials
Made from aerospace-grade 6061-T6 billet and stainless steel hardware for long-term durability under heat and vibration.
 
Performance Benefits
 
Increased mass airflow and smoother transitions through runners
Improved throttle response and turbo spool characteristics
Enhanced consistency across all cylinders under high boost
Ideal foundation for ECU tuning and big-power setups