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@ichiban.engineering
Reviews
Best looking and best quality valve cover you can buy for your Evo. The pictures on the website do not do it justice! The baffling system is top notch as well. They also answer all of your questions and are very polite. You won’t be disappointed.