I took on a little project for a friend this fall. He picked up a 383 that had been rebuilt quite some time ago, but has never really been ran. I tore it down and have been checking clearances, etc. It has a nice set of polshed stock rods, ARP bolts, and an older set of slugs in it with a pretty good dome. I just mic'd the rod journals and the big end of the rods. The crank is right at 2.344" across the board, with one being about .0002" smaller. The rods are all at 2.349", with one at 2.3485". That's a consistent .0025" clearance per side across the board. For a high comp roller 383, is that a pretty good number?

Assuming it had the stock Mopar rod journal size of 2.375 and it has been ground down to that size,.030 under, I would like to see a tiny bit more clearances using the old rule of .0010 clearances per one inch of rod journal size but that is me, I would rather have it a mile to loose than .0001 to tight.
That should work good as long as he pre oils it on the starter with oil pressure while spinning the motor around without the spark plugs in it before starting it

Your numbers don't subtract correctly. Is this a typo? If not then the math shows .0045" and .005" bearing clearance. That's quite a bit. Even if you used .011" under bearings it would be .0035" and .004". Though that loose wouldn't scare me the question is if the crank has been cut .031" under, why is there so much clearance ? I'd check the big ends of the rods for size.
Doug

I probably should have typed that differently. Yes, .0045-.005" total bearing clearance, or .0025" per side. Does that make more sense?

I'm not an expert, but since you haven't gotten too many replies I'll chime in. That sounds pretty loose for rods to me, I'd think your oil pressure would end up pretty low even with an HV pump and 20W50 oil.

Are you sure you have a standard .030 under bearing in there? As mentioned perhaps the rods need resizing. I'd shoot for more like .0025-.0030.

That's awful loose.

Double check everything. Then shoot for the .001 per inch of bearing journal plus .0005 which should put you at .002375 to .002875, or .0024 to .0029. If you are in that range, that will be fine. Just be sure and have full torque on the rod bolts when you check them.

I would use .0030 total max
You need to remember Mopar design the stock rod bearings to be wider at the rod bearing parting lines than they are up and down in the center of the bearings in the rods, that provides a wedge of oil in those wedges to continually coat the bearings on every revolution the motors makes
I use a lot of BB stroker cranks that have the BB Chevy 2.200 rod journals on them and I shoot for between .0025 and .0033 oil clearances in the center of those bearings, I like and use the narrow full groove main bearings and like between .003 to .0040 bearing clearances on them

Looks like I'd better do some more checking. I only snugged the bolts, then measured at a 45 deg. angle from perpendicular. Thanks guys!

Check them with the bolts torqued...

That would certainly add to the inner diameter measurement. When you torque the rods clamp them across the parting line. A couple pieces of aluminum in a vice will work.
Doug

Sure enough. Torqued a couple at random and rechecked. .0025-.0027"

It looks like God is watching after you

God, and the good folks of Moparts!

Perfect, make sure you check them all! Good luck!