Assembled; Chevy 348/409 Cubic Inch Engine; Natural; Aluminum; 220 CC Intake Port/ 115 CC Exhaust Port; 16 CC Chamber Volume; 2.19 Inch Intake Valve/ 1.72 Inch Exhaust Valve; 1.55 Inch Spring Diameter; Single; With Guides/ Seats/ Springs For Hydraulic Roller Cam