ProComp/Speedmaster aluminum heads

http://web.mit.edu/2.61/www/Lecture notes/Lec. 18 Heat transf.pdf

Here's at least one of the items I found which I've found interesting. Note that the aluminum head ran cooler, but that both materials remain below ignition temperature. That the spark plug tip and the exhaust valve are the hottest items in the chamber and so likely the greatest contributors to pre-ignition.

Also, the lower running temp of the alum cylinder head suggests that the reduced thermal resistance doesn't result in more heat extracted but instead in a lower surface temperature of the combustion chamber. At least that's my take-away..