Rod bearing alignment question

[gtc]

I started checking my 3.2's rod bearing clearances this weekend with plastigauge, and noticed that on one side, the bearing does not line up with the cap. Is this OK?
Perhaps just a result of the rods being resized?

The joint feels smooth, and the clearance was in spec with plastigauge placed on each side at about 8 and 4 o'clock.

Side in question:


This side lines up

[Lapkritis]

Perhaps an asymmetrical rod-resizing. Not ideal...

[gtc]

But will they work? Perhaps I should have them checked out again.

[Lapkritis]

My opinion is that they should be fine - just check your piston to head clearance carefully on each cylinder at 6 and 12 o'clock to ensure it's adequate.

Do you have your original bearings to see how they seat?

[jhg41977]

Have you tried swapping those bearings to a different rod set or swapping the halves?

[gtc]

I bought these rods already resized and fit with the arp bolts.
The rod length still measures 127mm, so compression height should still be ok, I think.
I do have the old bearings, so I can see how they fit, but the old rods are gone.

[jhg41977]

How about swapping the bearing from one rod to another?

[Lapkritis]

If these are second hand rods then my recommendations change but just a bit. This appears to be a simple asymmetrical resizing of the big end. I'd have them all double checked again perhaps by a different shop or machinist to ensure they're truly round. Whoever handled the resizing cut a bit more from the cap side than the rod. If you reverse the bearing - take cap side and put it in the rod and rod side and put in the cap - does the gap stay in the same position or does it move with the bearing half? For the rod side of the bearing shell to move some significant deformation would be occurring which I find hard to believe.

The concern of compression height is if the center of the hole is now slightly different on the big end. This translates to different finishing piston altitude at the top of each stroke. The difference may be minute/negligible but knowing that it's moving I'd still keep an eye on it.

[gtc]

After speaking with the local mechanic who has been advising me, we have come to the agreement that these should be fine as long as the clearances are within spec (which they appear to be, so far)
So i'll install them this weekend and report back with how it went.

[Lapkritis]

My only concern with an asymmetrical re-sizing is it may plastigage correctly even if out of round slightly. The result would be an extra thick oil film during operation between the crank and the bearing where the material is missing. You may be more prone to bearing failure as a result of normal operation. This is the devil's advocate position.

[gtc]

I'm going to check them all for any signs of ovality, though the first one measured out perfectly round, so I'm not too worried - yet.