[95chevy406]

What are undersize and oversize bearings.my crank was turned. 010 so i would need oversize right since there should be .010 more bearing metereal

 

[C-10]

.010 under for describing bearings.

.010 over for describing pistons.. (.010 .020 .030 etc)

 

[95chevy406]

.010 under for describing bearings.

.010 over for describing pistons.. (.010 .020 .030 etc)

Well my local parts store has them for over and undersize main bearings

 

[C-10]

Mic the crank. Use the numbers/size to buy bearings.

 

[1971BB427]

If you tell the parts store your crank was turned .010" under and they don't know what bearings to sell you, then I'd either get another salesman, or another parts store.

 

[cobalt327]

Well my local parts store has them for over and undersize main bearings

As said earlier you want 0.010" undersize bearings. The package will often have -10 as a suffix, or just 10.

The individual bearing shells are also marked for size. The King bearing below is a 0.010" undersize bearing:

There are 0.001" and 0.002" oversized bearings, sometimes used to selective fit bearings to journals for a closer tolerance. These are called X and XX bearings, respectively. I'm not aware of over the counter oversized bearings for a SBC that would be 0.010".

 

[1Gary]

While we are on the topic of bearings,here is a link on the difference kinds of bearings to choose from:

Getting Your Bearings: Engine Builder