Stop in for a cup of coffee

Good morning folks
Weekend plan: oil and filter on wife’s truck. Then got some ideas on the Duster. So as it is right now I have a cheapie refurbished battery, Tuff Stuff 100a alternator, cooling fans set to come on @ 210* and off @195* with a 195* thermostat. The car runs between 195-210 which I am perfectly satisfied with. What I’m not comfortable with is at idle in traffic with the fans on voltage drops to 12.1 ish. (typical Chrysler). It comes up to 14+ just off idle. So my thinking is first to replace the battery. I grabbed an Optima red top will install it this weekend. I also picked up a 180* thermostat. The thought being that with the 195* once the fans come on they never really shut off and once the car is moving I would think it should be able to drop below the 195 fan setting. And at least with the better battery it will better handle the fan load at idle. I also down the road I will update the fuel injection software, my understanding is the update has an option to raise idle to user specific rpm when fans are engaged. With the stall converter I may be able to set the idle high enough to bring charging voltage up without issue Am I over thinking this? Does any of this make sense?
Yes. Some A/C equiped cars raised the idle slightly when the A/C was on. It was done using an idle stop solenoid with a second position.

Try to get an alternator with better low rpm output or use a smaller pulley.
Getting an actual output test of an alternator, done at 14 Volts, is like asking for some great magical mystery. :rolleyes:
once in a blue moon you used to find this in a box with a remanufactured.
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Notice that it was done at 13.1 Volts. So it can't even be compared to the shop manual test, which is done at 15 Volts.
However 13.1 is just about high enough that the battery won't have to supply any juice. So at least its useful, unlike a test done at 12 or 12.5 Volts.
RPM is alternator, not engine.

In case your wondering, a test that was done regulating load at higher voltage would show lower max amperages