The temperature on my wife's 440 Six Pack Challenger would slowly creep up on super hot/humid days in prolong stop and go traffic.
Any driving speed over 20mph and the temp would cool down and stay cool.

Had a custom built 4 core 26" Mopar radiator, shroud and FloKooler water pump then swapped to a big Champion aluminum radiator with the same results.

I ended up installing a thin Maradyne low power draw pusher fan in front of the radiator with stock fan still in place.
Ran a simple toggle switch wired to a relay powered from the battery.

Don't need/use it much but it's nice to have if needed and the fan works great.
Car will sit at idle all day at 185 degree with the fan on.

Eventually I would like to wire in a temp sensor to automatically turn the fan on/off and keep the the toggle as a back up.