[bobcowan]

The pressure cap has a purpose. The boiling point is raised with higher pressures. I generally use a 16psi cap. Anything more and you have to wonder about the efficiency of your system. Higher pressures will also put a strain on the rest of the system, and everything will have to work harder. That costs you power and economy.

Yes, power = heat. The more power you make, the more heat it will produce. It's that whole energy conversion thing again. That's why people who couple a high powered stroker with a stock Mustang radiator have so much trouble.