The block has a few cosmetic differences from the original 340 Block, but it is machined to work with all 340 production components. Special features include brand-new castings made from high nickel cast iron for added strength (not a thin wall casting), 4-bolt main bearing caps, and 340 journal size. It has thicker webbing and pan rail (like the 1970 340 T/A version), a thicker deck surface and thicker bore walls in major and minor thrust directions. Block is rough bored at 3.900" to allow various bore sizes, from 3.910" to 4.080" (finish bore and honing required). Deck height is approximately 9.600".
