360/904 Torque converter

Why the change over from a 318 to the 360 Converter when you still using the 318 engine? I can't see any advantage to doing it. Stall speeds are about the same. Approximately 1700-2000 stall on both converters. Internal workings virtually the same on both converters.
Pop the weights off a 360 converter and you've got a 318 converter. We did that lots of times if a customer was in a rush and couldn't wait for us to finish up a run of converters for the 318.
904's (non lockup) found behind 360 engines 1975 -up.