SBC Little M Iron Block 9.025 4.125/350

The SBC Little M Iron Block 9.025 4.125/350 from DART is a bare engine block engineered for Small Block Chevy builds, serving rebuilders, performance enthusiasts, and restoration specialists who demand precision casting and proven architecture. This foundational component is the backbone of any 350 cubic inch Small Block project, whether you're assembling a street engine, marine powerplant, or race-prepped motor. Cast iron construction provides thermal stability and durability that modern aluminum alternatives struggle to match in high-heat, high-stress applications.

This bare block features a 9.025-inch deck height, 4.125-inch bore diameter, and 350 main journal configuration with four-bolt main cap design—the industry standard for reliable rotating assembly support and crankshaft retention under sustained load. The 2-piece rear seal design accommodates both traditional and modern crank sealing systems, offering flexibility during assembly. Weighing 255 pounds and measuring 19.2 x 14.9 x 23.2 inches, the block's substantial iron mass absorbs vibration and dissipates heat efficiently, critical factors in long-block longevity and consistent performance across varied operating conditions.

Builders selecting the SBC Little M Iron Block benefit from decades of Small Block Chevy refinement and aftermarket support—machine shops, cylinder head suppliers, and performance vendors stock compatible components universally. Installation requires proper bore honing, line boring verification, and deck surface preparation by a qualified machine shop to achieve optimal piston-to-deck clearance and main bearing alignment. This block integrates seamlessly with standard Small Block Chevy architecture, accommodating conventional and LS-hybrid configurations depending on your build objectives and budget.