4.500 Gen II Hemi Block Rough Bore

The 4.500 Gen II Hemi Block Rough Bore from Callies is a precision-engineered bare engine block engineered for serious builds demanding maximum displacement and reliability. Manufactured for high-performance applications in both street and competition environments, this block serves as the foundation for custom Hemi-platform powerplants where bore diameter and deck height are critical variables. Whether you're building a crate engine, restoring a classic Mopar, or developing a show-stopping restomod, this rough bore casting provides the raw material needed to achieve exact specifications and tight tolerances.

Callies' Gen II Hemi block features a 4.500-inch bore diameter and 10.725-inch deck height, ideal for stroke combinations that demand larger displacement without sacrificing the legendary Hemi architecture. The four-bolt main bearing cap design delivers the structural rigidity required for high-boost turbocharged builds and naturally aspirated high-RPM applications, while the two-piece rear main seal configuration enables modern sealing technology and improved reliability over legacy one-piece designs. Cast from ductile iron, this rough bore block provides excellent machinability, thermal properties, and the strength ceiling needed for engine combinations exceeding 800+ horsepower in demanding service.

Builders, machine shops, and performance enthusiasts rely on this block for custom stroker builds, race engine development, and high-horsepower street applications where OEM architecture meets aftermarket durability. The rough bore condition requires professional honing and cylinder finishing by a qualified machine shop to final specifications, ensuring proper ring sealing and bearing clearances for your intended power level and duty cycle. At 300 pounds and measuring 21 x 16 x 25 inches, shipping and handling should account for the substantial mass typical of cast-iron Hemi blocks.