[PatBuckley]

Late to this....

As Jamo mentioned, my aluminum block runs cool with no thermostat - just a 5/8 restrictor, one puller fan, stock Kirkham shrouding - although I did make sure that all the air that goes in the nose has to go through the radiator.

My water temps on a 95 degree day stay at 80 C while going down the highway and will go up to 90C when I hit stop and go traffic.

I am using an electric water pump that I think makes a big difference - I would feel comfortable letting my car idle for extended periods with no overheating.

I use distilled water with 15% coolant .