Bearing Problems-BBC
 

Gentlemen,

I am having some issues finding oversize race-grade crank bearings for a Gen 6 502 BBC block. My mains have been bored .020 over and the crank is STD. I can find the stock-style aluminum bearings .020 over but those will not hold up for long. Does anyone know where I can get custom bearings made or what company might manufacture oversize race/heavy duty bearings to fit? I can't be the only one who has run into this.....the rest of the block is cherry and is ready to go.

The engine will be a fuel injected 540. Ported Iron Eagle heads, Bob Madera ground cam. EMI Exhaust. Heavily modified MPI setup.

I appreciate any help or opinions.

Your mains are bored? Are you sure that is correct? I have seen .002 over rod bearings for the housing bore but never on the mains ....especially .020

Yes, Mains are bored .020 over....double checked with bore gauge. I can't believe that this isn't a common way to fix spun mains.

Clevite does make them, but not in a performance bearing. Only 1-4 are .020" over, The thrust stays std.
But... they only make them in .010 and .020 under journal size.

What was the dimension you came up with when you checked them with a bore gauge?

Im not trying to be difficult but you are saying the main housing bore is 2.9570/2.9580 ?

No, but my block is trying to be difficult! :lolhit:

I got the block for cheap (probably the reason) so I can't complain too much....everything comes at a cost I guess. Previous owner took it on trade so didn't know the history.

Yes, that is correct. What is the common way to repair spun mains? Sleeving them? Have heard of that being done before just figured that an over-sized bearing would be easier. There I go thinking again.

You can use shim stock under the bearing

:eek:

why didn't they machine the caps, then align hone the block to standard size?

No clue.....found all of this out after I bought block. Now I need to make it work.