>but remembering that cermics are insulators, (but my coffee
>cup would disprove this)
Well, seeing as how *my* coffee cup says "I KNOW MORE THAN
YOU DO!" on one side and "Ask Dr. Science" on the other, I'll
hazard a brief explanation. (That's brief for me; it means you
probably won't have to mount a separate file system for the reply.)
If you don't think your coffee cup is an insulator, try this simple
experiment at home. Make a pot of coffee (or tea, if you prefer) and
acquire two coffee cups: one a ceramic mug, the other a steel camping
cup. Fill each cup about halfway and wait one minute. Now put your
lips to each cup in turn. Hint: You might want to keep an icecube
around after you touch the steel cup.
>I now realize that I'm unsure of the result
>of the cermic tape. How would adding ceramic tape make the cockpit
>cooler?
When you pump hot exhaust gas through a header, the metal heats up
and radiates heat into the engine compartment. This lowers the
density of the air and heats the fuel, both of which tend to lower
power output. Exhaust tape (I'm not 100% positive, but I think that
the "ceramic" comes from a porcelainizing treatment that must be done
to an off-the-car component, while the tape is a fiberglass or other
insulating tape that can be applied in situ; I've done the latter)
forms an insulating layer between the metal of the header and the
engine compartment, and reduces underhood temperature by making
it more difficult for the header to radiate heat. The heat is instead
transferred downstream in the exhaust system, and thence to bolts that
stick up into the driver's seat. A side benefit is that if you
accidentally brush against a header covered with fiberglass tape, your
flesh will not scorch and stick to it the way it does to bare metal.
It's still not quite like a caress from a baby.
So the idea is to move the location at which the heat is radiated
from the exhaust system. You do this for either of two reasons: to
enhance performance by not diluting the charge air density with
excess underhood heat; or to enhance comfort by moving a "hot spot"
from the passenger compartment to a more remote area.
|