Billet Thermostat Housing – Mitsubishi Evo 6–9
 
Refined engineering. Reliable cooling. Motorsport-ready finish.
 
The Ichiban Engineering Billet Thermostat Housing for Mitsubishi Evo 6, 7, 8, and 9 is designed for builders who demand strength, precision, and modern plumbing flexibility without compromising OEM compatibility.
 
Machined from aerospace-grade 6061 aluminum billet, this housing replaces the weak factory cast unit with a structurally superior, precision-machined solution built to withstand high temperatures and pressure in demanding street and track environments.
 
Modeled after the Evo 9 thermostat housing, it includes the integrated coolant recirculation port while remaining fully compatible with Evo 6–8 applications. Every mounting surface and sealing face has been CNC-machined for perfect alignment and reliable fitment.
 
To modernize the cooling system, we’ve replaced the OEM barb-style turbo coolant outlet with a -6AN (AN6) threaded port, allowing seamless integration with braided lines and performance fittings. The housing also retains the OEM M14 coolant temperature sensor port, ensuring plug-and-play compatibility with factory electronics and aftermarket ECUs.
 
Instead of relying on messy RTV silicone, this housing seals using a high-quality Viton O-ring (included) that seats directly against the engine for consistent, leak-free operation and easy servicing.
 
Available in multiple anodized color options, this billet housing delivers both functional performance and a clean, motorsport-grade aesthetic.
 
Key Features
 
CNC-Machined 6061 Billet Aluminum
Stronger, more precise, and more durable than OEM cast housings.
Evo 9-Based Design
Includes coolant recirculation port while remaining compatible with Evo 6–8.
AN6 Turbo Coolant Port
Replaces OEM barb fitting for clean braided-line integration.
OEM M14 Sensor Port Retained
Direct compatibility with factory coolant temperature sensors.
Viton O-Ring Seal Included
Eliminates the need for RTV and ensures consistent sealing.
Anodized Finish Options
Multiple color choices to complement your engine bay.
 
Built for performance, engineered for reliability — the Ichiban Engineering Evo Billet Thermostat Housing is the ideal cooling upgrade for serious Evo builds.
 
⚙️ Fits Mitsubishi Lancer Evolution 6, 7, 8 & 9 (4G63)
⚠️ Note: Upper water neck is not included. It is available separately in another listing.
📧 For technical inquiries or custom finish requests: sales@ichiban.engineering