S54 Rod Bearings Size Recommondation needed

[JakeM346]

So I‘m back with a slightly odd rod bearing topic.

the basics
Crankshaft has been polished and is now 48,983 so basically within spec of 49 / -0,009 to - 0,025

The Conroe main bores are 2001 models and equipped with arp bolts. The out of round is within 0,005 for all of them so tolerable.
However the bores are all 0,014-0,023 oversized. BMW here allowing 0,013. (53,013)
The bore with King bearings therefore leads to 49,065
Which in total comes to a bearing play of approximately 0,088.
bmw allowing 0,030-0,070

considering that bearings will wear I do not want to have more than 0,050 bearing play.

therefore I need recommendations for bearings that might fit this. I was thinking about buying oversized but am not certain that they’ll fit.

therefore if anyone has enqountered this problem. I’m open for help.

thank you all in advance

[JakeM346]

[JakeM346]

CR6877XP-.025

I’m guessing these bearings should fit.
any experience?

I‘m also considering the acl race with 0,025 oversized. Guessing they should also fit.

[sapote]

However the bores are all 0,014-0,023 oversized.

The journal clearance of 0,088mm or 3 thouth should be ok, unless you can find a set that gives tighter clearance.

More concern is the rod big end ID which is now oversized. Do you have the dimension of the King bearing OD? You need enough crush dia to make sure the bearings won't spin against the rod.

[digger]

yeah the issue is the bearing crush because the housing is too large. presumably these are factory rods which cant be cut and resized either

[JakeM346]

Yes to both of your answers. The normal bearings can’t achieve the crush and the rods can’t be resized.
guessing that this is also the reason bmw changed them later in the build cycle.
the king bearings are in general pretty thin with only 1,993mm acl oversized are 2,006.
luckily it’s only one Conroe really out of spec while the other are only 0,001-0,002 out of spec.
therefore I’ll order oversized ones and measure the crush for them.
was just interested if someone had the same problem.