This listing is for an Elgin Industries (Elgin, IL USA) Pro Stock Sloppy Stage 1 performance hydraulic roller camshaft and lifters with matching valve springs for 1997-2007 GM LS V-8 engines without Active Fuel Management (AFM). Camshaft specs are below: with matching conical valve springs for 1997-2007 GM LS V-8 engines without Active Fuel Management (AFM). P/N E-1838-P+(16)RV9951S+HL2148S. Camshaft specs are below: CAM DESCRIPTION: Hydraulic Roller – Excellent idle, strong mid-range power, computer modification recommended. Compression: 10.5:1 VALVE LIFT (Intake/Exhaust): .560″/.560″ (using 1.7 rockers) ADVERTISED DURATION: (Intake/Exhaust): 285°/292° DURATION at .050″ (Intake/Exhaust): 216°/220° OVERLAP: 59° LOBE CENTER (Intake/Exhaust): 110°/118° LOBE SEPARATION: 114° RPM RANGE: 2,000-6,000 SPECIAL NOTES: This camshaft is not compatible with Active Fuel Management (AFM). An AFM delete kit and/or disabling the AFM through the ECM is required. Custom computer tuning required.