Engine - Cylinder Heads - Open Chamber Cylinder Head (Cast Iron) 1968-90

From GM Performance - This is Chevrolet's best cast iron cylinder head for high-performance big block V8's. It offers exceptional power at an economical price. This casting has 118cc open combustion chambers that reduce shrouding at high valve lift and improve engine airflow. The seats are ground for large 2.19 inch diameter intake valves and 1.88 inch exhausts. This high performance head has rectangular intake ports and square exhaust ports. It is machined for 7/16 inch screw in studs and guideplates (not supplied).