GM Small Block V8 Engine; 6.5L/ 396 Cubic Inch; Automotive; 491 Horsepower/ 509 Foot Pounds of Torque; Cast Iron Block/ Aluminum Cylinder Heads; 10.4:1 Compression Ratio; 4 Inch Bore/ 3.875 Inch Stroke; Front: Internally Balanced/ Rear: Externally Balanced; With Cylinder Heads/ Forged Steel Crankshaft/ Forged Pistons/ Hydraulic Roller Camshaft/ 4 Bolt Main Block/ 1 Piece Rear Main Seal/ 6 Inch Forged I-Beam Connecting Rods/ Oil Pan/ Timing Cover/ Valve Covers