5.0L 305ci Bare Engine Block

The Chevrolet Performance 10243869 is a 5.0L, 305 cubic inch bare engine block, specifically designed for 1986 and later style engines. This block serves as an economical and reliable alternative to sourcing an engine core, offering peace of mind with its OEM precision and durability. Constructed from cast iron, this block features a standard bore of 3.736 inches and a 9.025-inch deck height. It arrives fully machined and ready for your custom build, complete with installed camshaft bearings, brass freeze plugs, and oil line plugs. The design includes a 2-bolt main cap configuration and is machined to accommodate both hydraulic roller and flat tappet lifters, offering flexibility for various performance applications. This engine block is manufactured to the exact specifications of 1986-newer one-piece RMS (Rear Main Seal) 878 engine blocks. Key benefits of this block include a priority main oiling system that feeds main bearings first for enhanced performance at high temperatures, siamese cylinder bores with extra thick walls to resist cracking and improve ring seal, an open lifter valley for improved oil return, and blind head bolt holes that do not penetrate the water jacket. It also utilizes billet steel 4-bolt main bearing caps on all 5 mains for increased strength and durability. This bare block is an ideal option for building small block performance or marine engines, or as a direct replacement for a stock engine. Its robust construction and thoughtful design contribute to superior OEM precision and long-lasting durability.