I want to make my cylinder have a basic always rating in my family more a running length (which can be changed at any length but this more the base). Then I have the stem of the cylinder which must be the master one says you measure 10 of stroke more the initial base of the stem. But this one is not the same base as the cylinder. So my question is how to make it there are two different initial base for each object but while being linked by the race which is variable?

Thank you