a dry sump isn't absolutely necessary...neither is fuel
injection....neither is a magneto.
just a good way to hedge your bets. say your're in the mountains,
it's stormy, and you have turbulence. no matter what Gs or static you
are subjected to, the engine would get a steady supply of oil, fuel
and electricity.

i know resale value is diminished and the public perception is not
good. i'm just trying to understand the specific technical reasons
why. all i hear is that 1-auto engines MUST have psru and 2-therefore
turn high/spooky rpm continuously. then i fail to hear of any case
where a conversion project stumbles for lack of a psru. everyone who
dares to run direct is glad, and most of us agree there is nothing
scary about driving all day, every day, at 2900 rpm with a car
engine. you won't get 100% hp, but a camshaft and dual plane intake
change could help with that.

the rotaries need a lot of rpm to make decent power. so much that the
propeller is spinning too fast. i'm aware of this, but the plug and
ply magnetos i'm referring to are not avail for rotaries.

maybe aircraft engines have dual spark plugs...each cylinder fed by
two independent magnetos..is that the case? is that the safety
measure lacking in auto conversions? aside from the "psru myth", the
dual plugs are all i can think of.


On Aug 25, 9:13*pm, "Ramsey" @##@.^net wrote:
wrote in message

...





I was thumbing through a catalog from Speedway Motors. *They advertise
a magneto-type distributor. *Assuming you didn't come across a
thrashed race engine with magnetos, couldn't someone put together an
engine worthy of aircraft use, by simply 1) ordering an aftermarket
engine with fuel injection, such as the chevy "RamJet" crate engine,
2) adding a dry sump lubrication system to it (not too strange
addition to high perf cars nowadays), and 3)-adding the magneto from
Speedway. *Use direct drive to keep the RPM low and reliability high.
I doubt that today's hi perf crate engines lack the torque to turn a
prop at 1:1.

If this is unsafe, specifically why?

I know someone could fly within 100 miles of a t-storm and have the
static electricity play with the ignition system, but stop a magneto?
If you were struck with lightning, your auto-engine might stop, but
then your resin might burn and melt, leaving you with some loose
fiberglass to negotiate a crash. *Point I'm making is, experimental
planes near t-storms have bigger probs to worry about, don't they?

BTW, that magneto appears to be offered just for big and small block
chevy's. *Aside from that, the models they carry are "nostalgia
engines"...1950 hemis, flat head fords and the like. *Another caveat:
they cost $1100...but even with that and a $1200 dry sump system, we
are still way under the cost of an O-540.

OEM automotive engines are not usually designed to develop enough horsepower
at direct drive RPMs, to justify their finished weight, after including the
complete radiator, pump and coolant. Especially when compared to their
traditional aircraft counterparts.

Selection of an all aluminum small block, with all the lightweight and high
strength aftermarket parts can easily begin approaching the cost of a good
used aircraft engine, and still leave a lot of engineering to cost money or
build time, increase complexity and question reliability.

There is also still a question of resale value of the finished aircraft.

Lots of factors besides magnetos and dry sump systems. Why do you feel a dry
sump is necessary?- Hide quoted text -

- Show quoted text -