A mechanic only uses what you bring him, Every engine I have ever had built I brought the parts to the mechanic for assembly. If I brought him parts that shouldn't be used with new bearings and I don't tell him this, than I assume responsibility. Tom should have had a nitrated or aftermarket crank put in that engine to begin with. End of story.. If Tom didn't know, the mechanic didn't know, why as his friend did you not educate him on the subject. This thread could have been avoided.