On 6 Apr 2005 09:31:21 -0700, "monkers" wrote:

The two diameters I mentioned are the piston dia. How do I tell the
bore size , as it is different than piston dia. correct?

The bore size is only a few thousandths different than the piston dia.
In fact, if a cylinder is called out as a 4" cylinder then the bore
will be 4 inches and the piston slightly smaller.
ERS