Here is a pic of 1 of the rod bearings out of a motor of mine.
They all looked good Mains & rods , The crank looked great.
However all 8 of the upper half rod bearings looked like this 1 in the picture. Bottom rod bearings looked perfect. Any engine guys want to give their insite please feel free.

Blower Motor ?

Yes & I was woundering how long that would take , That was quick

Maybe a little Detonation

Detonation was my first thought with it being on the upper bearing. Just to clarify I said yes to the blower question ,
but it was actually a twin turbo motor when this occured.
( just for the record )

Some kind of detonation at one point,I just tore down my 540 blower motor (114 hours/950 hp) clevite h-series bearings,looked like they just came out of the pkg,other than a few rings that had spun around on the pistons and lined up there was zero signs of detonation,Smitty

Are the bearings "P" or "H" Series ?

Ditto

Long term, low level detonation.

Hey dean, They are H series