bearing clearance

[centredautomag]

Check main and rod clearance last night  I have .002 on main and .003 to.0035 on rods
I will get a set of rod bearing to go down to.0025. the question is ,should Igo up to.0025 or stay at .002.on main.
It is a scat rotating kit .The car is mostly street driven.

[chris_r]

I like .002 on mains thats what i put my fe mains on most of the time

[Barry_R]

I normally target between .0025 and .0030.  The .002 is where I put aluminum block engines (they grow).  You can definitely run them tight, but the crank and block need to be "dead on straight and round" - - something the average guy in a home garage may have trouble accurately measuring.  If you are .0005 too loose nobody will ever know, if you are .0005 too tight, everybody will know.  Its a risk versus reward thing.

[blykins]

I’m a .001” per inch of journal type of guy.  So for an FE main or a Cleveland main, I’m gonna be on the upper “2’s” or .003”. 

On BBC rod journals, I’ll be at .002-.0025”.  For FE rod journals, I’ll be .0025-.003”.

Those numbers have served me well in the past.

[fekbmax]

I have to agree, these guys know there stuff.  If it's a FE rod journal then I think the .oo3 is gonna be fine for you. I'd be more concerned about the .oo2 on the mains. Like Barry said, unless its line honed (properly) and dead nuts straight that .oo2 is a bit snug.

[My427stang]

I like .0025-ish, but would live with .002 without a care in the world if it was a fresh cut crank and straight block. 

[WerbyFord]

One easy check:
With just fresh oil on the mains, torq the caps & give the crank a good spin by hand.
After you let go (maybe even without cutting yourself on the block edge), the crank should keep spinning free.
As much as 1 full turn of free spin, but at least 1/4 turn.
If it stops as soon as you let go it's too tight.
If it goes a full turn it will run extra good.

[19cougar68]

OK so I now have targets for the main and rod clearances when I finally begin assembly on my engine.  What about cam bearing clearances, lifter to bore clearances or any other clearances / tolerances I need to verify.  Sorry to the OP for the slight high jack.  If the additional questions require a lot more information about my build I'll start a new post.  Thank you.

[Hemi Joel]

I would leave the rods just like they are. I wouldn't want to go any tighter than .003 on a performance build. And .0005 loose is not worth changing. I've run .0035 -.0039 with zero issues.