Final answer:
The correct procedure is to bore the engine cylinders to the specified size and then hone to the clearance specification, which ensures the right fit for the piston within the cylinder.
Step-by-step explanation:
The correct procedure for boring cylinders in a parent bore engine is to bore to the specified size and then hone to the clearance specification. This means that the initial boring process will create a cylinder that is very close to the required dimensions for the new piston but will not include the necessary clearance. Once the boring is done, the honing process then precisely finishes the cylinder surface to provide the correct clearance for the piston, which includes accounting for thermal expansion and contract, and the oil film needed for lubrication. Honing is a critical step because it not only sets the final dimension but also improves the surface finish to ensure the piston can move smoothly within the cylinder. The clearance generally relates to the relative size difference between the piston and the cylinder wall to allow for thermal expansion and engine operation.