Cosworth CNC ported cylinder heads feature dyno tested and flow bench proven ports, engineered for maximum usable 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 high performance applications.
CNC Ported/Machined finish port
New Castings
Hand blended finish work
Intake 14.63% (average) 22% (max) increased flow
Exhaust 30.56%(average) 41% (max) increased flow
4-angle Inlet Valve job
3-angle & radius 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
20001699 is designed to fit 2007 WRX STI EJ25 (2.5L) North American spec vehicles with air injection ports or 2006-2007 Euro/Asia applications using electronic throttle control.
