be careful with the temperature you take the measurements at.
A crank journal of 51mm would expand by 6.5µm every 10C.
This corresponds to several bearing size steps!
You also need very accurate gauges to measure this well.
Best is to get both rods and crank to the same temperature and plastigauge the bearing gap with new shells of a known size.
To get them to the same temperature, let them sit in the same room you take the measurements at least over night. The crank takes some time to adapt to the room's temperature.
A crank journal of 51mm would expand by 6.5µm every 10C.
This corresponds to several bearing size steps!
You also need very accurate gauges to measure this well.
Best is to get both rods and crank to the same temperature and plastigauge the bearing gap with new shells of a known size.
To get them to the same temperature, let them sit in the same room you take the measurements at least over night. The crank takes some time to adapt to the room's temperature.
