The Edelbrock #60499 Performer Bare High Compression cylinder head is designed for Big-Block Chevy Oval Port V8 applications. These Edelbrock Performer Series cylinder head is 50-state street legal and provide outstanding performance from Idle-5,500 RPM's. The Edelbrock Performer head is perfect for street performance, daily drivers, street rods and muscle cars where seat-of-the-pants performance is needed. They also feature the highest quality intake and exhaust valves and valve springs.