Cosworth Built Mitsubishi EVO 4G63 CNC ported Big Valve Cylinder head (KK3672)

Cosworth CNC ported cylinder heads feature dyno tested and flow bench proven ports, engineered for maximum real world power. Each new cylinder head is ported on a 5 axis machine to ensure consistency and perfect port shape every time. Additionally, larger intake (+1mm) and exhaust valves (+1mm) are utilized to help increase flow. Cosworth CNC ported Big Valve cylinder heads come complete with a performance valve job, hi rev (max 10,500rpm) valve springs with titanium retainers and are ready to install. Perfect for big turbo applications. A flow chart for the modified head is available by downloading the technical document on the left.

Specification:

CNC Ported/machine finished port - New OE Castings

Hand blended finish work

Intake ・26% Increased Flow (max)

Exhaust ・18% Increased Flow (max)

4-angle Inlet Valve job

3-angle & radiused Exhaust Valve job

Valves are lapped

Back-Cut Inlet Valves

Heads are Ultra Sonic cleaned prior to assembly

Heads are Serialized and sport a machined Cosworth logo

+1mm Stainless Steel Intake Valves (1800 degrees max.)

+1mm Inconel Exhaust Valves (2400 degrees max.)

Performance Valve Springs

Titanium Retainers

Hardened Steel Spring Platforms

Reshaped combustion chamber