Maybe this is peculiar to the 380 engine, but the front four bearing towers have no openings on the bottom to the block for oil supply. The rear bearing tower does. The oil then runs through the groove in the rear bearing and up into the pipe which feeds the front bearings via the plastic tees plugged into the tops of the bearing towers. If one of the tees or drip holes gets plugged, this could oil starve the associated bearing/lobe/rocker.
As far as my oil tube shifting, it may have had some help from one of the ham-fisted mechanics that the previous owner hired to fix a hesitation problem. The tees and end caps were still attached to their respective bearing towers, but the tube had been moved foward about 1/2" within the tees recently as evidenced by a shiny area on the pipe in front of each tee. This misaligned the holes and bingo, fried bearings.
By the way, I just installed the new camshaft and bearing towers
and the camshaft seems to be hard to turn by hand with the rockers not yet installed. Is this normal? How tight should it be?
What could cause this tightness?
Even a broken clock is right twice a day.
'66 MGB Roadster
'85 Mazda RX7
'91 Chevy P/U