strength of open diff 8 3/4?

Just as strong as a cone-type ......... until you peg-leg it
The cone-type SureGrip can be found in all three Center Sections; and is the same two-pinion Unit
The open center is the also the same among the three. .
The Strongest is the 4-pinion Clutch-Type Trac-Loc. How much stronger? IDK but on the street, with street-tires, in stock tubs; I sure wouldn't go hunting for one ......
unless maybe I had Caltracs and a high-friction clutch..........
The basic differences between them all is the pinion size, and the bearings. With 7260 Joints, yur likely to break them first.