Main and rod bearing question

I am in the process of replacing the bearings in my motor on a rebuild. (1mz-fe) How do you know what size main bearings and rod bearings to get. Is there something that you measure to determine the size. Looking on several parts web sites, it list several different ones like, .001, .010, .020, etc. How do I find out what I need. Sorry guys I'm new to this internal engine rebuild stuff. While I'm at it, the same with piston rings. What determines what size piston ring that is needed. Thanks

This post has been edited by doory100: Jan 18, 2016 - 12:46 PM

when you took the block apart, if the bearings looked good, no scratches, and the crank journals are good. then use the same bearing that came off. the number is printed on the bearing.

if you tossed them already, there are numbers on the crank and numbers on the block. there is a matrix that you cross them up and it tells you what bearing to use.

Well everything is looking good the crankshaft jurnals are in great condition. The cylinder walls are also in good order their isn't even a carbon ridge at the top of the wall. I was more interested in the ordering process as it asks if you need oversized or standard. I'm thinking a quick deglaze of the walls then just ordering standard everything? What do you think?