Silicon Nitride bearing tolerances

[unclematt]

Hi All, I am curious if anyone can share some info on how close of a tolerance you can achieve with full ceramic bearings (including ceramic races), preferably in silicon nitride. I am looking for both roller or ball configuration, and the ability to withstand heavy duty use. I am considering their use on a diesel crankshaft, but I mention this only to illusrate the load they will be under. Please don't respond with reasons not to use them in this applciation, as the engine is not a typical diesel.

any help would be appreciated.