Good point. I also took some time, about 2 weeks, to install the electric fan after I removed the mechanical one. No overheating problems. At that time I lived in Oakland, CA which has a cool breeze in from the pacific ocean. Now I live inland with summer temps up in the 90-100F (~40C?), and the fan kicks on quite a bit. I even think I want to try a lower temp switch.
As far as size, I don't think that matters a whole lot. If it is too small, the fan will kick on more often. In the 116 cars, the early ones had one fan taking up half the radiator area, and the later ones had dual fans. Maybe the early fans didn't last as long since they operated more often. I don't know.
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