MTFCA Forum

I realize this is a bit of a contentious topic, but I would like to put it out there just the same.
Question is, whether to add Babbitt to the sides of the rear main bearing saddle on the upper (block) side. One school of thought argument against is that in order to get the Babbitt to stick you should tin the cast iron. Because this area is oil soaked removing the oil from the cast icon is difficult if not impossible.

However in this case I have align bored the main bearings out to accommodate a large Chevy crankshaft. Along with the larger diameter the bearing width has been reduced which means cutting faces of the saddle. This obviously exposes fresh cut cast iron, which I would think? Help the tinning operation.
One of the negatives will be that in the process of boring out the bearing bores the area of the thrust contact is also reduced.
Wondering what had been done in the past, and what were the results?
Trying hard to no re invent the wheel on this project,

Dave

Don’t bother with thrusts on the block. The best thing you can do is put a bronze thrust bearing on the front of the rear cap. Permanent solution.

If you are going to add thrust babbitt to the block too couple of way you could do it. Angle the face back top to bottom to lock the babbitt and/or drill anchor holes like the saddle for a mechanical lock.