On Thu, 23 May 1996, Todd Francis wrote:
 Upon inspection of the coated heads
> the coating looked great. There was already corrosion in the cylinder bores
> where the green "O" rings slide into(yes I used  vw blue megabuck coolant).
> This area was not coated. This coating is the same stuff that they put on
> piston tops. I understand NASCAR racers have been using it for years. It is
> meant to keep heat from transfering through. I figure that is a bonus
> because it should keep some of the heat of the head from getting to the
> spendy little rubber gasket that seals the coolant in. I think that the
> cooler the gasket stays the longer it will last.

Thanks for your input. Hot heads are the main reason our VW motors have 
such low compression ratio (and thus low power). These "magic" coatings 
will hopefully make our motors last longer and perform better.

I've also been thinking about the benifits of plating the outside of the 
jugs with either zinc or copper. One problem with these air cooled 
engines is that the iron jugs just don't conduct heat well enough. Zinc 
is cheap and conducts about twice as good as iron, copper is about 10 
times more conductive. The trick is to prevent the jugs from rusting and 
enhance thier thermal conductivity at the same time. I haven't checked on 
the thermal conductivity of the copper oxide yet, though, but I'm usre 
it's worse than pure copper. It may be better than zinc, though. The nce 
thing about this is that enhancing the thermal conductivity of the jugs 
will keep the heads cooler, which means more power and better 
reiliability. It's a thought, anyway.

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Dirk Wright 						       wright@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"
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