I have a 1993 Lt1 I am rebuilding. I went to the machine shop and had the crank polished and the block align bored. I have clearances of .0025 in on all five journals. They said it is Ok and they go has large has .0030 in. The haynes manual specs say maximum of .0022 in. Is this ok. Also what should the rod bearing clearances be? Thanks.

 

I usually use .0025 on mains #1-4 and .003 on #5. Helps in getting a little more oil to the thrust bearing.

I shoot for .0023-.0025 on the rods.

-Mindgame

 

I set mine up .002 across all mains, .0025 on the rods. I think the .003 is a little to much for the mains.

 

If you're concerned, get a set of STD and a set of .001 OS bearings and use half from each to close it up .0005

 

.003 is too much for #1-4, but not for #5. I don't know too many people doing it differently... at least not on a high-performance build.

For a performance build that sees a good deal of rpm and track time, .002 is too tight. But that's just my opinion.

-Mindgame