[Formulajones]

To help explain that further, using dad's car as an example.

I run a 160 stat in it, but as I mentioned, during our summer months when it's 100+ degrees, the car typically runs 175-ish. It pretty much just stays in that area cruising on the highway. It actually cools down a few degrees as soon as you take an exit and putt around 30-35 mph on back roads.

All that means is that the current radiator and shroud setup, and the current engine combo, that's about as cool as I can get the engine to run on hot days. That's all the system is capable of. When it's hot outside, it's just not going to run at the 160 stat rating.

Now on cooler days below 80 degrees or so, it's not uncommon to see it stick right around 160. It can sometimes see 157-158 as the thermostat just cracks open, and will fluctuate right there. That's the thermostat now doing it's job making sure the engine stays at that temperature. It can get hotter, but it won't get colder.

Now if I put a 180 stat in it, it would no longer run 175 on the hot days obviously, the thermostat would force the engine to run at least 180, and since I know the cooling system is capable of keeping it colder than that I suspect it would stay right at the thermostat rating. Slowing down on the backroads wouldn't cool the engine down any further either, as that thermostat would force it to run there.