GM Small Block V8 Engine; 6.3L/ 383 Cubic Inch; Automotive; 4 Bolt Main Cap; 4 Inch Bore/ 3.75 Inch Stroke; 1 Piece Rear Main Seal; Front: Internally Balanced/ Rear: Externally Balanced; With Cast Steel Crankshaft/ Forged Pistons/ Hydraulic Roller Camshaft/ 5.7 Inch Forged Connecting Rods With 150,000 PSI Bolts/ Oil Pan/ Timing Cover/ Harmonic Balancer