The Edelbrock #60185 Performer RPM head is designed for use with 1961-79 Chrysler 361-440 c.i.d. Wedge engine applications. The Edelbrock #60185 Performer RPM head is perfect for street performance, daily drivers, street rods and muscle cars where seat-of-the-pants performance is needed. This cylinder head delivers great throttle response and power from 1500 to 6500 rpm. They also feature the highest quality intake and exhaust valves and valve springs. For use on pre-pollution controlled vehicles only.