[Barry_R]

The bearing alloy in performance bearings is decidedly better. Not even open to question. Clevite chose to go to a narrow bearing a few years ago, Federal-Mogul still chamfers the bearing for radii clearance. Either approach works.

On rod bearings either one works. On passenger car main bearings Clevite and others have gone to using the same shell for both upper and lower positions. This puts a huge "oil hole" and a groove in the loaded lower section of the bearing - greatly reducing it's surface area and hence increasing the psi loading. A really crappy idea.

FE and Cleveland engines can use the same main bearings - the only significant difference is in the tang location. You may either remove the tangs or add notches. The tangs are for production assembly location only and serve no real purpose. Cleveland race main bearings are available in +1 and -1 sizes while FEs are not.