Maximum performance, bracket racing, heads up and super classes. Over 7,500 RPM, 500+ cubic inches, a great head for maximum effort comp or bracket cars. Dart's PRO2 24 Deg 380cc CNC heads have been revised with larger 2.350 in. intake valves and a revised port design for improved airflow and a substantial horsepower increase! These cylinder heads were designed to make competitive engine building easier and less expensive by incorporating the rugged features of our famous Race Series casting into a ready to use, professional quality competition cylinder head. Every intake port, every exhaust runner, every valve bowl, and every combustion chamber is 100% digitally CNC machined for the ultimate in consistency. Assemblies include Stainless Steel valves, premium springs, locks, retainers, guide plates and seals.