Well I thought I'd provide an update - of sorts. No root cause was ever determined. The bearing manufactures looked at the pics, the engine machine shop and I also went over all the parts with a fine tooth comb, and nothing stands out as installed incorrectly. So far the best "guess" was that the cam bearing that #4 cam bearing with the oil holes that feed the rockers began to "wipe" and closed off part of the hole that allows the oil through. From there the rockers did not get enough oil and began to sieze, increasing he load on the valvetrain and ultimately pushed even harder on the cam bearings. The cam bearings were installed correctly and the cam turned easily in the bearings prior to assembly. The bearing "expert" contaced by my engine machine shop said that the cam must have been installed "dry" and taht caused the failure. This did not happen and I even have pictures of the installed cam with assembly lube seen clearly on the edges of the cam/bearing. So no root cause, the mains and roda are not as bad as they look and the marks in the cylinders came out with cleaning.
So the block has been prepped again with new bearings and will be assembled within the next few weeks. Does anyone have any better theories or experience?
