Eagle Chevrolet Big Block w/ 2pc Rear Seal 25.5cc Dome Piston 4.31in Bore Balanced Rotating Assembly

If you're rebuilding the heart of your Chevrolet Big Block for street use, a balanced rotating assembly like this one from Eagle is a solid foundation. This assembly is designed for pump gas, naturally aspirated applications, making it a great choice for a street-strip build where reliability and performance on regular fuel are key. It takes the guesswork out of matching critical internal engine components, ensuring they work together harmoniously from the start.

This particular assembly includes a 4.000-inch cast crankshaft, which is a strong core for many performance builds. It's paired with 6.135-inch I-beam connecting rods, known for their good strength-to-weight ratio for street applications. These rods are secured with 7/16-inch ARP 8740 bolts, a well-regarded fastener for their reliability under stress. The pistons are Hypereutectic KB 25.5cc dome units with a 4.310-inch bore, designed to work with the 2-piece rear main seal common on many big block Chevy engines. They come with plasma-moly file-fit rings, which allow for precise gap setting to match your engine's specific needs and ensure good sealing. King SI rod and main bearings are also included, providing the necessary interface between the rotating assembly and the engine block.

This assembly comes balanced from Eagle, which is a crucial step for reducing engine vibration and improving overall smoothness and longevity. Balancing the crankshaft, rods, pistons, and rings as a set is a time-consuming process that this kit handles for you. Keep in mind that this assembly is not CARB approved and cannot be shipped to California. Always refer to the manufacturer's installation instructions for proper assembly and break-in procedures.