Rod bearing anomolie ???

Aloha,
I run a Gen III (6.1 Hemi) NA on methanal the only bearings available are the tri layer bearings, I have put about 12 to 15 runs mostly short passes on the bearings and there loosing there arch at the part line, so much that they just fall out of the rod (Aluminum) when checking. Clearence is approx .0035 and I use 60 wt oil. There has been no sign of detonation and the upper's are; on one bearing flatened about .0015. The Piston tops show a good burn pattern but it just wipes off with a little oil on a rag, I believe I'm still way fat. I have had as much as 42* advance in the mag but the motor dosen't sound or appear to labor. Researching, I have discovered that 14* to 16* at WOT is the sweet spot for these heads, would the advance predicate the bearing problem??
Mahalo Doug