Originally Posted by malcb
If the heat is generated inside the item then black will radiate the heat best, if the heat is going to be radiated into the item, ie from a hot engine the shiny surface will reflect more heat. Shouldn't be a huge difference between a polished surface and a slightly dulled casting.
Roughness - wonder if the larger surface area helps with radiation?
All quite marginal - the IC and and ice will make this machine quite different to an SRT! (Plus the lack of interior and custome ECU)
The reason I asked is because I've thought about cleaning up the casting on my intake plenum boxes(?) and polishing it out...but was worried about the excessive heat. The underhood heat on these cars is crazy. Even the plastic engine cover is scorching after you park the car.
I was also wondering how thick they were because some of that casting is quite rough and would take some work to get through it.