I don't agree on aircraft duty cycles.  Cars need only 30 HP average.
No way would they use more HP and still get 25 to 30 MPG on the
highway cycle. Run the numbers. Use an extraordinary BSFC of .40 if
you wish. Most car piston engines are good for only 300 hours
using aircraft engine duty cycles.

Aircraft engines need 150 HP continuous and 200 HP for five minutes.

Toyota was awarded 800 hours TBO by the FAA as I recall after an

expensive

total redesign while a real aircraft engines have 2000 hour TBOs. That

is

why Toyota gave up on the V8 and went with Lycoming. No pilot in his

right

mind
would buy a half million dollar airplane and then have to rebuild the
engine after only 800 hours.

What I was suggesting is that Bombarder was making blocks for some auto
manufacturer. I happen to know that Wankel GmBh Korf Germany was part of
a larger die casting plant making die casting for MB. Bombarder is
a BIG company. 200 million is not out of the question.

As far as holding up... the block is only a small part of the problem.
What happens is the automotive block is made too short for aircraft

service

not allowing enough radius in the crank journals  hence not enough

fatigue

life
for the crankshaft at high continuos power. This was a main part of why
Orenda
went belly up with the Chevy big block based V8 aircraft engine despite
having spent
50 million on the project. They eventually solved the water jacket

cooling

problem by
redesigning the block and heads but they failed to add the necessary

length

to the block as that would require yet another new crankshaft forging

die.

Further more inline engines and V engines are trying to shove the crank
out the bottom of the block adding to the overall engine weight compared

to

a horizontal opposed configuration. Orenda should have started with a

clean

sheet of paper using the horizontal opposed configuration as Honda is

now

doing
with their joint project with Continental.

As far as the turbo compound RX8 engine 30 MPG in the RX8 EPA high way
driving cycle surely will make a dent.

I can't think of many 120 degree V6's out there. Most are 90 degree.

Some

are
less. VW comes to mind. I think Ferrari has a 120 degree V6 but I don't
think it
is die cast. I could be wrong. Ferrari spends over 300 million each
year for their Formula One racing program.

We are REALLY REALLY lucky to have the Mazda rotary :)

Paul Lamar

Doug Rupert wrote:

Honda builds the engine for Bombardier.
Doug Rupert

I did not know Honda had a 120 degree V6.
Why are they building a 120 degree V6 for Bombardier and a horizontal
opposed engine for Continental?

Paul Lamar

Bombadier is heavily into personal watercraft, and that was my suspicion
when I saw
the engine at Oshkosh (it was in their watercraft tent) . They vehemtly
denied this
as I would expect them to. Aircraft engines lead an easy life on duty cycle
compared
to marine useage, and the market is much more capapble of providing the
sales to
support the tooling costs. There are a lot of new lightweight marine engines
hitting
the market, that could be very viable if you are ready to use fairly "deep"
reduction
ratios. Vance

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