Stovetop experiments do not mimic the 'closed cooling system of a car (open only when radiator cap capacity is exceeded'.

That is why the car cooling sytem is not as good w/o a radiator cap.

Running a pure water with a cap rating of 0.9 (0.9 x 1 Bar or 14.7 PSI} will increase its boiling point to 115 degrees C. The boiling point of water increases 3 degree F per PSI, a 25% coolant mix will further improve this with other benefits.

Adding a surfactant like 'Redline's water wetter' will improve further your cooling sytem.

You can read this link to give you another view (although there are a lot of this kind in the web really).

http://www.turbomagazine.com/feature...t_results.html

I would say that the readers should read more on this subject before giving a final conclusion.