[Badbubba]

Just as you said. Black absorbs radiant energy well. It also emits radiant energy well. So, hot exhaust gases heat the headers. The headers being black will radiate the heat into the engine compartment. Thus raising underhood temps. The idea of ceramic coating is to insulate and contain the heat in the header pipes to maintain gas velocity and reduce engine compartment temps. You will feel more heat from a black object than a shiny one, even though they are the same temp. I didn't say touch, bc now that would be conduction. Black is more efficient at radiating energy. It's very easy to burn yourself with the polished coated header bc you can't feel the heat coming from the pipe. Next thing you know, you brush up against it and ouch you #$@&!! Did this when double checking the steering stem. The cast manifolds give off heat fairly well, especially after they oxidize. I'm not saying there is a night and day difference, but there is a difference. Hopefully you can find someone with the coated and polished headers so you can feel for yourself. If you use a point and shoot temp gun, you will need to adjust the emissivity. Most cheap temp guns don't have this adjustment. They will read dark and oxidized objects fairly well, but will display a significantly lower reading of a polished shiny surface. Bc they measure the amount of infrared energy " radiant energy" coming from an object to calculate the surface temp. Emissivity is the correction factor that must be applied. A black body has an emissivity of 1, the polished silver coated surface is probably .25.