4G15 and 4G18 engines come from the same engine family Does this mean their blocks are interchangeable?

No, it does not necessarily mean that their blocks are interchangeable. While the 4G15 and 4G18 engines belong to the same engine family, they may have different block designs or dimensions. The interchangeability of engine components, including blocks, depends on various factors such as the specific models, years, and variants of the engines.

Some engines within an engine family may share similar design concepts, but they can still have different internal architecture, mounting points, and overall configurations. Manufacturers often make changes to engine blocks, such as bore and stroke dimensions, material composition, casting methods, and integration of auxiliary components.

To determine whether the blocks of the 4G15 and 4G18 engines are interchangeable, you would need to consult specific technical information or consult with a qualified mechanic who has knowledge about these particular engines. They can provide you with the necessary information and guidance to confirm the compatibility of engine components.