PRC 237cc CNC Ported Cylinder Heads

The Texas Speed & Performance PRC 237cc CNC Ported Cylinder Heads represent the pinnacle of LS cathedral port performance, engineered for 370 cubic inch and larger engine applications with a 4.00" or larger bore size. These heads are proudly made, cast, and machined in the USA, utilizing new Precision Race Components castings. The intake runners are fully CNC ported to 237cc, while the exhaust runners are also fully CNC ported to 84cc. The chambers are CNC machined to 68cc, and CHE bronze guides are incorporated. This package includes a TSP .660 spring kit featuring PAC valve springs and titanium retainers, ensuring durability and performance. The valves are sized at 2.100" for intake with a hollow stem and 1.600" for exhaust with a stainless steel construction. Flow bench testing indicates the 237cc port can achieve over 330 CFM, making it suitable for a wide range of applications, from street engines with smaller camshafts to full-race engines. The flow data at a 4.030" bore plate (without exhaust pipe) shows significant airflow, with .500" lift yielding 325 CFM intake and 227 CFM exhaust, and .600" lift reaching 334 CFM intake and 235 CFM exhaust.