Classic/Antique Car Repair: Main bearing failure on 1946 Plymouth, cam bearings, taxi fleet

Question
I have restored my 1946 Plymouth Coupe to original but keep having the reoccurring problem of main bearing failure. I know that it was problem but have they come up with any new advances i.e. phosfor bronze that might help

Answer
I am not sure that main bearing failure was any more of a problem on these engines as any other. This engine was the darling of the taxi fleet back in the day so it could not have been too bad. In the late 40's I was just entering the auto repair field. I would check the bore alignment of this engine and make sure that it is straight. Then I would look at all of the bearing clearances. If you are replacing the mains and setting them up tight and the rod bearings and cam bearings are looser then the oil will flow to the looser bearings and could actually cause the tight mains to starve for oil. The next thing is the weight of the oil. With bearings set up with minimal clearance running a heavy weight, 30 for instance, will also cause the bearings to run dry. Alignment and clearances are the solution.
Brad