60455 Cylinder Head Performer Rpm

Performer heads are 50 state emissions legal and are designed to fit emissions related engines. Performer RPM heads are perfect for street performance daily drivers street rods and muscle cars where Seat-Of-The-pants performance is needed. These heads give great Torque and Horsepower up to 6500 RPM. Features -Engine Compatibility - Chevrolet 7.4L/ 454 Cubic In. Engine. -Style - Assembled. -Finish - Satin. -Material - Aluminum. -CNC-Machined - Yes. -Combustion Chamber Volume cc - 110 Cubic Centimeter. -Port Shape - Oval. -Port Location - Standard Intake/ Raised Exhaust. -Valve Diameter - 2.19 In. Intake/ 1.88 In. Exhaust. -Includes Valves - Yes. -Includes Rocker Arm Studs - Yes. -Rocker Arm Nut Thread Size - 7/16 In. -Valve Lock Type - 7 Degree. -Valve Stem Seal Type - Umbrella. -Valve Guide Material - Bronze. -Valve Seats Machined - Yes. -Number Of Springs Per Valve - 1. -Includes Guideplates - Yes. -Includes Damper Spring - Yes. -Runner Volume cc - 290 Intake/ 110 Exhaust Cubic Centimeter. -These Oval Port Heads Will Support Over 540 Horsepower With 9.5 - 1 Compression When Used As Part Of The Total Power Package. -Semi Open Chamber Design Maximizes Efficiency With Streetable Compression Ratios. -Smaller Than Stock 11/32 In. Valve Stems Promote Excellent Flow And Lighter Valve Weight. -These Heads Give Great Torque And Horsepower Up To 6500 RPM. -Its fits for various makes & Model.