Timing - again, ceramic

[Dirk Wright]

On Mon, 16 Sep 1996, Todd Knighton wrote:
> 	Beware of Ceramics!!!
> 	Especially on internal engine parts, i.e. pistons, combustion chambers,
> valves, exhaust ports.

Does this include Jet Hot Coatings? They have pictures of coated valves 
and piston tops inthier brochure. I can understand this might be a 
problem in air cooled engines, where the parts expand more due to the 
higher operating temperatures.

> 	Coating headers as well tends to make the material run much hotter,
> thus disintegrates quicker, especially on mild steel.  If you just go to
> a good stainless steel header, the coefficient of thermal heat transfer
> is so slow, the heat transfer is practically better than a mild steel
> header ceramic coated.

Yeah, that's the idea behind stainless steel valves for air cooled 
engines, they run cooler that way.


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Dirk Wright 					            wright at uspto.gov
"I speak for myself and not my employer."               1974 Porsche 914 2.0
"A real hifi glows in the dark and has horns."            1965 Goodman House
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