John Gibbons wrote:

Paul and all,

    I was discussing the new diesel that Diamond has on its new

twin. If

they come close to what

they claim, it looks like they will have a good engine ( not as good

as

a wankel of course !!! ).

The idea of diesel seems to offer some very good benefits,

particularly

in regard to cheap and

available fuel, simplicity and safety. I started to wonder about the

possibilities of dieselising

a Mazda. I figure the weak point would be the apex seals and

possibly

the side seals. Paul you

just said yesterday that the engine itself is almost bullet proof.

What

is the lowest compression

ratio you could use with diesel and how could that be accomplished

in a

rotary ? Some of it could

be blown in but I would think you would still need to increase the

CR

for start up and idle before

your turbo or supercharger start to work. How is the CR changed

between

the NA and turbo Mazda's

?

Thanks,

John

That is the A class Mercedes econo box engine. There is some doubt the

FAA

is going

to certify  that. If they certify that they will have to approve the

Mecanair

Mazda rotary. Forget the true diesel cycle for a rotary. Won't happen.
The combustion chamber shape would be so thin as to be unworkable. It

will

run on direct injected spark assisted diesel fuel however.

It would be better to do a turbo compound rotary and enjoy the same

low

fuel

burn characteristics of a true diesel.

All the current hype on aircraft diesels applies to Europe where

diesel

fuel is half

the cost of gasoline due to the silly commie tax policy. (Tax the hell

out

of

the poor dumb suckers till they quit working :)) An aircraft diesel

engine

is not worth the extra weight in the USA. At best the fuel burn

reduction

at aircraft power levels is only 15 to 20%. Not worth the stink, noise
and weight. On the other hand if you have a source for 80 cents a

gallon

farm diesel fuel... go for it :)

Paul Lamar

Not quite that good, our marked diesel I pay $2.19 cdn per US gal.

John

Well then there is little advantage to a diesel unless you can get cheap
tax free farm diesel fuel like we do in the states. Come to think of
it what do you pay for gas in Canada now? Here in California gas is
about $1.65 per US gallon. In AZ it is a $1.45. Aviation fuel is $2.10 per
gallon. When I was in Germany and Italy recently auto gas was about
$4.40 US for four liters. A bit more than one US gallon.

People are starting to drive around over there in telephone booths
equipped with wheels. Notice the flat tire.

Paul Lamar

On Vancouver Island off the west coast we are paying $3.10 Cdn./US gallon,
or about $2.05 US for regular unleaded. 100LL $4.58 in Victoria and $3.78 in
Nanaimo, 30 miles away. There is always something fishy about the prices as
there are places where the cost of fuel has got to be higher, yet they are
always cheaper. Victoria is always at the top of the price list. When you
factor in the exchange rate we can't save any money by hopping over the
border like was happening 7 or 8 years ago ( it never worked for those of us
on the island, just Vancouver ). The top end of your country was littered
with lots of huge gas stations cash in on the price difference. As the
spread between our dollars increased things changed and now they're all
ghost stations. I think we're all paying too much regardless of where we are
!

John

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