How do modern cars regulate temperature so well?

It runs 190 most of the time, but when it's hot outside it climbs over 200 - 205....
That's without AC which I am definitely going to add AND a mild 318 build....couldn't imagine what it would do with AC and more hp (stroker planned in future)
Some days when the outside temperature is mild, 190 around town and 180 on the freeway. ...
It's all over the place.

All seals in place and good condition.

Jeff
That does not seem bad at all.