This production small-block Chevy is cast-iron and features a 4.00-inch bore. This basic design is relatively short and basically rigid. Unlike many other manufacturer's V-8s, the small-block Chevy casting only drops 1/8-inch below the crankshaft's centerline. Chevrolet's engineering team in the early '50s did this to minimize weight and allow the main bearing caps to locate in a broached longitudinal slot. Small-block Chevys generally provide an economical foundation for many performance buildups.