What Is the Ideal Cylinder Head Material for Maximum Horsepower?

[J.A.W.]

I understand heat soak (or cold soak) to be a condition where the system components have been heated/cooled to a particular uniform temperature. For example, if you were performing a cold start test procedure on a vehicle, you would cold soak the vehicle in an environmental test chamber for a period of time sufficient to ensure every component in the system being tested was stabilized at the test temperature. It can take a fair amount of cold soak time to bring an entire car or truck down to -20degF for testing.

Yeah r-r, & your particular example also applies to putting an ambient/room- temp 6-pack of beer in the fridge..
..they'll cool down to a drinkable level quicker, if you take 'em out of their package, & allow the cold air better access..

On the the other hand, you'll note the fridge itself has to really work harder at pumpin' - in hot ambient temps - to chill 'em..

The previously noted usage of the P&W R-2800 as a hard-running fighter mill brought the issue of inter-cooler/after-cooler
"heat-soak" into focus too, & with the air-cooled radial unable to utilize the primary liquid-coolant already available to
the likes of R-R V12s,, a more bulky/less efficacious air/air system (plus ADI ) was necessary - to approach similar boost levels..

The liquid-cooled engines still had the ADI option on hand - to increase the MAP, & could increase cooling capacity in a
location remote from the engine, but convenient for the airframe & include drag reduction/Meredith effect utilization..

Interestingly the the WW2 battle between the big, lazy specific output radials, & highly-strung inlines has continued
into the Reno air races, with the much smaller capacity Merlin-powered Mustangs finishing on top, by using extra external liquid sprays on their radiators & low-drag "boil-off" oil-coolers - to prevent "heat-soak" power fade, & to maintain a quicker race average speed than the air-cooled opposition..

[Speed_Demon]

I'm trying to understand the relationship of thermal conductivity and power in an ICE. I've heard that if you have 2 identical cylinder heads only one was cast from aluminum and the other iron, the iron one would produce more power. (Assuming there is no pre-ignition) I guess this is because the aluminum conducts heat better and as a result more energy is dissipated into the cooling system during combustion -energy that should be used to force the piston down.

So is there a better material or coating that will allow higher compression without the energy "bleeding off" into the cylinder head?

It sounds like you get it pretty well. The main concern is the fuel used and the weight. With ceramic coatings available you can get the thermal eff. of the iron head and the weight savings of the aluminum. Here is one of the most popular I've seen and they describe the what/how and why's.