What is the lower half of 1996 318i bmw engine called?

The lower half of a 1996 BMW 318i engine is typically referred to as the "engine block". This is the main structural component of the engine, housing the cylinders, crankshaft, connecting rods, and other vital components.

It's important to note that the term "lower half" is not technically precise in this context. The engine block is a single, unified component. However, it's common to talk about the "lower half" of the engine when referring to the engine block as opposed to the cylinder head, which sits on top of the block.

If you're looking for more specific information about a particular component within the engine block, please provide more details.