Summer Water Temp Baseline?

Maximum allowable? What exactly are you looking for?

Above 230*F and you’re overheating.

Much above 210*F to 220*F or so isn’t somewhere I want my car to stay for very long. But if it’s 100*+ and you’re running the AC and stuck in traffic or under heavy load I wouldn’t be surprised to get there occasionally.

200*F is the top of the “normal” operating range for me, so if it’s 200*F I’m not at all worried.

That’s all for inlet or sending unit temps. Radiator output should be 30*F or more cooler. Preferably more.

***edit***

Also remember your IR gun is reading surface temperature, not water temperature. So you’re getting the surface temperature of whatever you’re pointing the IR gun at. So the water temperature may be a little different, and how much it’s different will depend on the surface. Ie, the manifold and the hose may not have the same difference compared to the water temp.