4G63 Billet Valve Cover – Precision. Performance. Perfection.
The Ichiban Engineering 4G63 Billet Valve Cover is the ultimate evolution of a timeless icon — crafted for builders, racers, and purists who demand more than just performance.
Starting with an OEM Mitsubishi 4G63 valve cover, our engineers performed a full 3D laser scan to capture every contour and mounting detail with micron-level precision. From there, we rebuilt it — stronger, smarter, and infinitely better. The result is a valve cover that looks factory from afar, yet reveals its billet soul and engineering excellence up close.
Machined from a single block of 6061-T6 aerospace aluminum, this masterpiece eliminates the weaknesses of the original cast design. Underneath, our signature dual-stage “tunnel” baffle system controls airflow and oil movement with unmatched precision, dramatically reducing blow-by and keeping oil where it belongs — even at redline.
Each cover comes ready for serious performance use, featuring integrated AN-10 ports for external catch-can setups, perfect sealing tolerances, and compatibility with the OEM plastic coil cover for that clean, stealth OEM+ aesthetic.
Why It’s Better
Designed From OEM DNA: Laser-scanned and digitally modeled from the original 4G63 for exact fitment and gasket alignment.
Machined to Perfection: Fully CNC-machined from 6061-T6 billet aluminum — built for strength, heat resistance, and flawless finish.
Tunnel-Core Baffle System: A CFD-optimized internal design that forces air and oil through a longer path, separating vapor for cleaner crankcase pressure and less mess.
AN-10 Fittings Integrated: Built-in fittings on the side for catch-can or breather setups — no welding, no guesswork.
Custom Anodized Finishes: Choose from multiple colors or request a custom hue to make your engine bay truly yours.
Lifetime Warranty: Because real engineering stands the test of time.
⚙️ Compatible with EVO 4–8 and EVO 9 MIVEC heads — please select your version when ordering.
📧 Custom requests or anodizing options: sales@ichibanengineering.com
