In my previous post I explained how my 93 na 940 with 260k miles overheated suddenly, and then I immediately pulled over and shut off the engine. I eventually found out that a newer WAHL thermostat was the cause, it had failed, and replaced it with a Vernet (apparently the OEM brand). Here is the million dollar question.

Did I do any engine damage?

The car runs perfectly fine, although with this mileage it is hardly as the "swedish chef" might say "a spring chicken". My coworker feels head damage is inevitable, although it might take 20k to show up, but the damage is done and the head has warped.

I might add that, by inspection, it's likely the thermostat failed suddenly. I did not drive the car with the temp gauge pegged, but shut down as soon as the needle caught my eye. There was plenty of fresh oil in the crankcase, as well.

Can anyone share experience or perspective on this?