Do I need to upgrade my alternator with these fans?

My opinion would be that if you sat in traffic at night in the rain with the fans on and the headlights on that you'd be drawing the battery down with the setup you have, because you won't be getting enough idle amps.

I have the same fans, EFI, 13A fuel pump (aeromotive 340 lph), the regular lights, stereo, etc. My 78A 12SI delco keeps up so long as the wipers are on, but if you do, its drawing power from the battery, (its typically 12.9V at idle with this setup). This alternator charges a ton better at idle than yours does. I would go for a 94A 12SI delco in your case and forget about it forever. Its a really easy swap so long as you have a cut-off wheel and a welder.