4.1 Main Bearings

[Quietman]

I received a call from my machine shop that they were having trouble with the Sealed Power main bearings I had given them. Using a ball tip mike, they showed me that the some of the bearings had a half thousandth or more variance from the left to right side of the bearing. They indicated they have seen a lot of variantion on several brands. They ordered in a set of ACL bearings and found less than 2 tenths variation.

It never occurred to me that companies whose business depends on precision could sell a product that varies that much. Perhaps not a problem with chevys, but with such close tolerances on a Buick, I am wondering if anyone in the Buick community has had a problem or even has gone to the trouble to check?

Thanks

 

[CTX-SLPR]

I'm assemblying mine with Clevite 77 bearings. They aren't race stuff but they are what Dan at DLS told me were fine for a non all out motor. He recommends Federal Mogul race bearings for those that are kicking it up.

 

[JM_in_TX]

King bearings are very good for our cars. You can get them from several sources, Full Throttle Speed is one and I could even get them from a local machine shop. I put the .001 undersize mains on my stock crank and ended up with .001 clearances. My engine will hold very good oil pressure at hot idle. The quality control is supposed to be better because they are precision bored, not cast like the others. Everyone that I talked to recommended them, including Jack Cotton.