Anyone got information or documentation on the casting codes on the pistons and/or rods from the '70-83 Z car engines? I need to identify some parts.

Also while I'm asking, was the bore the same for all of the above years and only the stroke and/or rod length changed?

I don't have any codes. But I do know that the stroke lengthened in '74 to make the L24 into the L26, and then the bore was increased in '75 to make the L26 into the L28. So only two different bore sizes, and two different stroke lengths for the three engine sizes we got here in the USA.

Ampco and Atsugi are the two names I've seen cast into L-6 pistons. I'm not sure if any of the numbers cast into the pistons mean anything specific. They will also have a little Nissan logo like many of the other parts on the car.