[nUcLeArEnVoY]

200 is nowhere near overheating, and in SoFlo during the summer, I'd say you're doing pretty well. As for while idling, as people have been stating: temp creep at idle is usually an airflow issue, but coolant flow also plays a role. I run a flowkooler as well and it's been fine for me, but honestly I don't think it performs any better or worse than a stock cast impeller so I probably spent extra $$$ for nothing. The vane design on mine is probably different from your's, too, as I'm assuming you're using an 8-bolt bump vs. the 11-bolt I'm using.

But another factor with coolant flow other than the water pump design is also the pulley, which plays not only a role with how fast the pump spins, but also the fan. Make sure you're using an overdriven (i.e. smaller diameter) water pump pulley when you're running AC. The factory usually did this with AC-equipped cars due to the additional load the AC puts not only on the engine, but also the additional load the condenser puts on the radiator.

Idle temps are also affected by ignition timing. Any street motor should be using vacuum advance, and for a '66, those were usually hooked to manifold vacuum which is ideal in this case. Higher ignition timing will help an engine run cooler at idle speeds, so you may want to consider looking into that as well.

Your best bet is to just research the stock configuration for your car and engine as far as the fan and orientation goes. A fan that is positioned too close to the radiator will pull air only from the area directly in front of the fan - you move the fan back a little more and correctly positioned in a shroud, it will funnel air throughout the entire radiator as it should. This principle works well with 2nd gen radiators as 78w72 stated above.

South Florida will really put a cooling system to the test. I live in Miami-Dade county and I usually drive my T/A in the mornings and evenings so I don't need to use the A/C, since while my A/C does work and blow cool air, it strains the motor a lot and the engine temperature climbs very fast while I'm using it. May be something wrong with the compressor or an insufficient charge stressing the system. I've never bothered looking into it, since if I'm not running AC, my car conversely has trouble REACHING operating temperature after totally overhauling my cooling system.