Does This Debunk the "Coolant Can Flow Through the Radiator Too Fast" Idea???

Newbomb Turk said
EXACTLY. YOU MADE MY POINT.

The cooling system SHOULD have the capacity and capability to maintain WHATEVER your thermostat opening is.

On my piece of garbage I use a 160 thermostat and it barely climbs to 168-170 on 100 plus degree days.

And I could drop a 195 in there and that would be as cool as it would get BUT it won’t get any hotter than that either.

Why?

Because my cooling system will maintain 160 degrees. If I take the thermostat out it won’t even get to 160 because the system will cool it.

I run a 160 degree thermostat because I drive it in the winter and I need a defrost.

So both statements are correct.

If you are using a 190 thermostat and you drop down to a 160 and it still runs at 190 then you KNOW your cooling system isn’t up to even par.

This just means you have an overly robust cooling system that keeps your engine cooler than the factory service manual recommends. That's fine as long as you know that there are drawbacks to that.

The cooling system isn't going to just keep the temperature at whatever the thermostat opens up at. What happens if you use no thermostat? What about a 100* thermostat?