A Simple Auto Engine Conversion

[[email protected]]

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.

[Philippe[_2_]]

wrote:

> 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.
and you are over the weight of an O-540...

But it will fly


--
Volem rien foutre al païs!
Philippe Vessaire Ò¿Ó¬
** Posted from http://www.teranews.com **

[Gig 601Xl Builder]

wrote:

> 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.

Did they have one for the Corvair?

[[email protected]]

nope...you'd have a tough time getting fuel injection / dry sump in a
corvair motor too. if you don't mind carbs, and like the 1960s
engines, you could also consider a buick aluminum

...in fact, you could look for a shop that specializes in making range
rover V8 w/EFI work outside of their OEM environment. range rover was
essentially a small aluminum buick v8....but i think it was
discontinued around 2000. still, the range rover engine is probably a
lot easier to find than the buick version. but you'd probably end up
with 33% more weight than the corvair


On Aug 25, 8:35*am, Gig 601Xl Builder >
wrote:
> wrote:
> > 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.
>
> Did they have one for the Corvair?

[[email protected]]

On Aug 25, 4:25*am, Philippe > wrote:
> wrote:
> > 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.
>
> * *and you are over the weight of an O-540...
>
> But *it will fly
>
> --
> Volem rien foutre al païs!
> * * Philippe Vessaire *Ò¿Ó¬
> ** Posted fromhttp://www.teranews.com**

not if it's an aluminum aftermarket racing block. i don't think GM's
ramjet crate engine is offered with aluminum blocks though...but in
all honesty, there are a dozen shops that could make an alloy ramjet
chevy engine in their sleep.

i suspect an alloy chevy small block weighs less than an O-540, and an
alloy chevy big block weighs a little more...so you get to choose. i
assume you need a radiator, but not a psru.

given the output of the big block in the neighborhood of 500hp, maybe
it would be fair to compare it's weight/fuel consumption to a TSIO-540
or normally aspirated O-720 or PT6 turboprop.

my reason for starting this thread is simple...i've read a lot of "mad
scientist/decades of refinement" auto conversion stories...only to see
this magneto option in a consumer catalog as a 2 wire bolt in! i
realize magnetos are in $18,000-48,000 corporate-sponsored race
engines, but then you'd just as well buy a 220hp Franklin for the same
money.

[JohnO]

On Aug 25, 3:48*pm, "
> wrote:
> 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.

How about this one:
http://www.vertical-aviation.com/press.aspx?pr_id=53

[Ramsey]

> 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?

[cavelamb himself[_4_]]

Most popular engine conversion of all times?

http://www.pilotfriend.com/aero_engines/engine_specs/Lycoming%200%20360.htm

[stol]

On Aug 24, 9:48*pm, "
> wrote:
> 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.

These conversions are done all the time.. All it takes is alot of
work... But that is what homebuilding is all about right ?

Ben
www.haaspowerair.com

Watch this video too. http://video.google.com/videoplay?docid=-7272451917550730841&hl=en

[[email protected]]

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 -

[[email protected]]

On Aug 25, 9:06*pm, JohnO > wrote:
> On Aug 25, 3:48*pm, "
>
>
>
>
>
> > wrote:
> > 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.
>
> How about this one:http://www.vertical-aviation.com/press.aspx?pr_id=53- Hide quoted text -
>
> - Show quoted text -

that's a nice engine. everyone says "ooh -- auto...dangerous" but no
one can explain exactly why. let's shrug on exactly why that gm
engine will get us killed, and just pay $38,000 for a 180hp
engine. ...or let's pay 6000 for a 2 stroke 80hp engine and hope
people dont laugh.

i can appreciate the engineering/advantages of aircraft turbine
engines, but the piston engines are overrated. given the choice of a
2 stroke rotax airplane, or a VW 4 stroke conversion, most mechanics
agree the VW engine is safer!!!

[[email protected]]

On Aug 26, 6:32*am, stol > wrote:
> On Aug 24, 9:48*pm, "
>
>
>
>
>
> > wrote:
> > 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.
>
> These conversions are done all the time.. All it takes is alot of
> work... But that is what homebuilding is all about right ?
>
> Benwww.haaspowerair.com
>
> Watch this video too. * * * *http://video.google.com/videoplay?docid=-7272451917550730841&hl=en- Hide quoted text -
>
> - Show quoted text -

what is the cost and the hp? how does it compare to a 18,000 USD,
220hp franklin engine? i couldn't easily tell from the webpage.

playing the devil's advocate...

some coil gone wild or short in the system could afflict both msd
boxes. maybe he has two coils.

aero electricity experts do have some compelling arguments in favor of
magnetos. maybe non-magnetos is ok because your experimental plane
doesn't see t-storms....maybe it doesn't even see IFR/MVFR. i
presonally would want a magneto....i know the mechanic working on the
plane will be less likely to make mistakes or be confused.

[Morgans[_2_]]

> wrote

OP: 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.

Morg: I think you are hung up on the features of that overpriced aircraft
engine. It is hard to believe that the dry sump will do any better than a
good old oil pan, unless you plan on some inverted flight, and if you
worried about some turbulence, an oil accumulator would keep oil flow
temporarily. Anyway, most aircraft engines do not have dry sumps.

Morg: Unless you use a header tank, fuel injection will not guarantee
keeping fuel going to run the engine. I do like fuel injection, and there
is no reason to not have it, and lots of other reasons to have it, but
again, not absolutely necessary unless you are going for an inverted
package.

Morg: Magnetos over electronic ignition? What breaks down more often, a
magneto, or electronic ignition? What is better at making an easy starting
engine, running with the spark at the appropriate timing? Magnetos are old
hat, so if you want reliable, go with dual pickup, dual coil(s) redundant
electronic ignition with a battery supplied emergency backup power source
for the ignitions. The not having a dual plug is the only slight trade off,
because you can use a two into one spark system to tie the dual ignition to
the one plug.


OP: 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.

Morg: PSRUs have another value over direct drive, in that the prop
gyroscopic loads and thrust loads are removed from the crankshaft. They can
be MAJOR problems, up to and including broken crankshafts. An example are
the Corvair cranks broken (in part) from prop adapters that are too long,
with heavy props. With a V-8, you are going to have a heavy prop, and a
short adapter will make an unstreamlined cowl. The PSRU also raises the
thrust line to get better prop to ground clearance. So yes, those are some
reasons a conversion stumbles without a PSRU.

Morg: Bottom line, it would be very wise to use some type of extra external
bearing to help with soaking up the thrust loads and gyroscopic loads. A
PSRU does that for you. The PSRU also gets some more HP so the HP to weight
ratio is better. As far as spooky high continuous RPMs go, I think you
have been listening to some of the critics of conversions too much.

Morg: When have you heard of people being concerned at running a marine
auto engine at too high constant RPMs? Never. They run at RPMs that would
worry me much more, and faster than most people run airplane conversions.
You can choose what drive ratio you want to run. A conversion running at
3,000 RPM is too fast for a prop, but not too fast to make me uncomfortable.
I would not worry at running a conversion at 3,800 RPM for extended periods
of time. I sure run my boat engine at higher RPMs than that.

Morg: In short, I think your concerns about PSRUs are unfounded. You can
run any speed you want to, and higher than a normal prop speed. You get the
other advantages I identified, and get more HP from your heavy engine. You
don't have to run at peak HP, but it sure would not hurt to run faster than
prop speed.

OP: 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.

OP: 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.

OP: 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.

I hope I gave you a little to think about. There are companies out there
with well engineered, time tested, reliable PSRUs. To me, it is not the
myth that would keep me running direct drive, but the desire to get a better
powered package, with the isolation of prop loads on a crankshaft that IS
NOT DESIGNED to take prop loads.
--
Jim in NC

[Ron Wanttaja]

On Tue, 26 Aug 2008 21:07:46 -0700 (PDT), "
> wrote:

> everyone says "ooh -- auto...dangerous" but no
> one can explain exactly why.

1. Ignition systems with insufficient redundancy.
2. PSRU failures.
3. Difficulty in implementing efficient liquid cooling systems.

Ron Wanttaja

[stol]

On Aug 26, 10:43*pm, "
> wrote:
> On Aug 26, 6:32*am, stol > wrote:
>
>
>
>
>
> > On Aug 24, 9:48*pm, "
>
> > > wrote:
> > > 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.
>
> > These conversions are done all the time.. All it takes is alot of
> > work... But that is what homebuilding is all about right ?
>
> > Benwww.haaspowerair.com
>
> > Watch this video too. * * * *http://video.google.com/videoplay?docid=-7272451917550730841&hl=en-Hide quoted text -
>
> > - Show quoted text -
>
> what is the cost and the hp? *how does it compare to a 18,000 USD,
> 220hp franklin engine? *i couldn't easily tell from the webpage.
>
> playing the devil's advocate...
>
> some coil gone wild or short in the system could afflict both msd
> boxes. *maybe he has two coils.
>
> aero electricity experts do have some compelling arguments in favor of
> magnetos. *maybe non-magnetos is ok because your experimental plane
> doesn't see t-storms....maybe it doesn't even see IFR/MVFR. * i
> presonally would want a magneto....i know the mechanic working on the
> plane will be less likely to make mistakes or be confused.- Hide quoted text -
>
> - Show quoted text -

Watch the video..............

Also. This is the "homebuilt" section. Why would you have a mechanic
work on your plane you built? With a simple redrive ratio change and
a different grind on the cam my package can produce twice the power I
am making now, that of course would be limited to a short duration
like 10-20 minutes for takeoffs and emergencies. My motor is a 10,000
rpm bottom end small block detuned using top end limiting items. These
same motors run wide open for 4+ hours every Sunday and the failure
rate is amazing low at those RPM's. Your fears are based on ol wives
tales and some "less then perfect" installations. Yes, there are guys
who actually go to a junk yard and get a worn out motor, bolt it in
their homebuilt and crash. That is NOT the way to do it... <G>

Ben
www.haaspowerair.com

[[email protected]]

On Aug 26, 11:43 pm, "Morgans" > wrote:
> > wrote
>
> OP: 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.

You'd better think twice about being in the mountains in
stormy weather and turbulence. You'll have other problems besides oil
supply. In any case, wet-sump aircraft engines fly in the mountains
and turbulence all the time and have no oil issues. It's the weather
that kills the flier.

> Morg: Magnetos over electronic ignition? What breaks down more often, a
> magneto, or electronic ignition? What is better at making an easy starting
> engine, running with the spark at the appropriate timing? Magnetos are old
> hat, so if you want reliable, go with dual pickup, dual coil(s) redundant
> electronic ignition with a battery supplied emergency backup power source
> for the ignitions. The not having a dual plug is the only slight trade off,
> because you can use a two into one spark system to tie the dual ignition to
> the one plug.

The use of 100LL fouls plugs rather often. Two plugs are handy
for that, and the extra plug improves power output.

> OP: 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.


> Morg: Bottom line, it would be very wise to use some type of extra external
> bearing to help with soaking up the thrust loads and gyroscopic loads. A
> PSRU does that for you. The PSRU also gets some more HP so the HP to weight
> ratio is better. As far as spooky high continuous RPMs go, I think you
> have been listening to some of the critics of conversions too much.

Very good point. Auto cranks were designed for torsion loads only,
not thrust or gyroscopic loads, and they tend to break when subjected
to such loads.

> Morg: When have you heard of people being concerned at running a marine
> auto engine at too high constant RPMs? Never. They run at RPMs that would
> worry me much more, and faster than most people run airplane conversions.
> You can choose what drive ratio you want to run. A conversion running at
> 3,000 RPM is too fast for a prop, but not too fast to make me uncomfortable.
> I would not worry at running a conversion at 3,800 RPM for extended periods
> of time. I sure run my boat engine at higher RPMs than that.

Marine engines have a couple of advantages that aircraft
conversions do not: A ready supply of cold coolant, and a drive system
that doesn't apply and thrust or gyroscopic loads on the crank.
Running an auto engine at or near max power settings, like we do in
boats or airplanes, generates huge amounts of waste heat that autos
don't when they're cruising unless they're pulling heavy trailers, in
which case a trailer-towing package becomes necessary. This includes
much larger cooling capacity. Autos typically cruise at around 25-30%
power, boats and airplanes at 65-80%. I have experience with both
marine and aircraft liquid-cooled conversions, and believe me, the
boat is easy to keep cool.
Aircraft engines are built with big cooling capacity right from
the start. And they're designed to produce large amounts of torque at
lower RPM, which means the basic cylinder geometry is different. And
they're designed to do all this without weighing as much as a bridge.

> OP: 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.

You still won't get 100% unless you're at rated redline, which no
prop will stand for. Most direct-drive conversions run a much shorter
prop to allow a higher RPM (propeller tip speed and centrifugal forces
are the concern) and shorter props lose efficiency big time, so
performance, especially takeoff and climb, suffer considerably.
One horsepower is 33,000 foot-pounds per minute. To get it we do
this: Torque x RPM x 6.28 divided by 33,000. RPM is one of the
factors, and a PSRU is usually needed to get the engine's RPM up to
its designed redline so it'll generate the claimed HP. Anything less
represents a loss, which means a heavy, underpowered airplane.


> OP: 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.

Boy oh boy, are we at that level of expertise? You'd better do
a LOT of research here before deciding that you have answers that the
rest of us don't.

> I hope I gave you a little to think about. There are companies out there
> with well engineered, time tested, reliable PSRUs. To me, it is not the
> myth that would keep me running direct drive, but the desire to get a better
> powered package, with the isolation of prop loads on a crankshaft that IS
> NOT DESIGNED to take prop loads.

Yup. Lots of folks have done the work already and found it much
more difficult than they imagined when they started out. I wouldn't
want to think that I could improve on any of it on a first try.

Dan

[Morgans[_2_]]

> wrote

"Morgans" > wrote:
>> > wrote

Ooops, you attributed the following to me, and it was the OP.

>> 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.

End OP quoted paragraph.

>> Morg: When have you heard of people being concerned at running a marine
>> auto engine at too high constant RPMs? Never. They run at RPMs that
>> would
>> worry me much more, and faster than most people run airplane conversions.
>> You can choose what drive ratio you want to run. A conversion running at
>> 3,000 RPM is too fast for a prop, but not too fast to make me
>> uncomfortable.
>> I would not worry at running a conversion at 3,800 RPM for extended
>> periods
>> of time. I sure run my boat engine at higher RPMs than that.
>
> Marine engines have a couple of advantages that aircraft
> conversions do not: A ready supply of cold coolant, and a drive system
> that doesn't apply and thrust or gyroscopic loads on the crank.

Yes, but a well designed and performing cooling system cools all the extra
heat an engine can produce. Don't you thinik the P-51 did ok with their
cooling system? There are homebuilt auto engines flying all over the place,
for over 2,000 hours that do not have a problem dealing with waste heat.
The ONLY time they have a problem is if they have to run sitting on the
ground, or too long of a taxi. Flying, they cool just fine, after they have
all of the bugs out of the cooling system. I will not say that some people
have problems, but there are hundreds of people flying car engines that have
absolutely NO problems with cooling in the air.

As far as the crank loads, that is taken care of with a PSRU. Another non
issue.

> Running an auto engine at or near max power settings, like we do in
> boats or airplanes, generates huge amounts of waste heat that autos
> don't when they're cruising unless they're pulling heavy trailers, in
> which case a trailer-towing package becomes necessary. This includes
> much larger cooling capacity. Autos typically cruise at around 25-30%
> power, boats and airplanes at 65-80%. I have experience with both
> marine and aircraft liquid-cooled conversions, and believe me, the
> boat is easy to keep cool.

And so are water cooled airplane engines, with good cooling systems, and it
is not that hard of an issue to deal with.
--
Jim in NC

[Copperhead144]

On Aug 27, 1:14*am, Ron Wanttaja > wrote:
> On Tue, 26 Aug 2008 21:07:46 -0700 (PDT), "
>
> > wrote:
> > everyone says "ooh -- auto...dangerous" but no
> > one can explain exactly why.
>
> 1. Ignition systems with insufficient redundancy.
> 2. PSRU failures.
> 3. Difficulty in implementing efficient liquid cooling systems.
>
> Ron Wanttaja

The ignition system redundancy is surmountable but doing so will
increase weight as does the PSRU. However PSRU and liquid cooled
engines predate the current trend of using high preformance automobile
engines. This however does not infer that problems and short service
life of the PSRU and engine have not always been an issue with
avaition engines.

Joe

[Jim Logajan]

Ron Wanttaja > wrote:
> On Tue, 26 Aug 2008 21:07:46 -0700 (PDT), "
> > wrote:
>
>> everyone says "ooh -- auto...dangerous" but no
>> one can explain exactly why.
>
> 1. Ignition systems with insufficient redundancy.
> 2. PSRU failures.
> 3. Difficulty in implementing efficient liquid cooling systems.

But doesn't the Rotax 912 have reduction gearing and liquid cooling? It is
getting put into an awful lot of aircraft models - particularly LSAs.

[Peter Dohm]

"Jim Logajan" > wrote in message
.. .
> Ron Wanttaja > wrote:
>> On Tue, 26 Aug 2008 21:07:46 -0700 (PDT), "
>> > wrote:
>>
>>> everyone says "ooh -- auto...dangerous" but no
>>> one can explain exactly why.
>>
>> 1. Ignition systems with insufficient redundancy.
>> 2. PSRU failures.
>> 3. Difficulty in implementing efficient liquid cooling systems.
>
> But doesn't the Rotax 912 have reduction gearing and liquid cooling? It is
> getting put into an awful lot of aircraft models - particularly LSAs.

That's true, and the biggest annoyance (of which I am aware) is that they
have increased the recommended "idle" speed to increase the service life of
the PSRU--which is of the spur gear type. I don't know whether any of the
belt or chain type PSRU installations have a similar requirement.

As to cooling: there were a lot of liquid cooled aircraft engines in WWII,
but the the aircraft they in which they were installed looked a lot
different from their air cooled counterparts.

Peter

[[email protected]]

On Aug 27, 3:32 pm, "Peter Dohm" > wrote:
> "Jim Logajan" > wrote in message
>
> .. .
>
> > Ron Wanttaja > wrote:
> >> On Tue, 26 Aug 2008 21:07:46 -0700 (PDT), "
> >> > wrote:
>
> >>> everyone says "ooh -- auto...dangerous" but no
> >>> one can explain exactly why.
>
> >> 1. Ignition systems with insufficient redundancy.
> >> 2. PSRU failures.
> >> 3. Difficulty in implementing efficient liquid cooling systems.
>
> > But doesn't the Rotax 912 have reduction gearing and liquid cooling? It is
> > getting put into an awful lot of aircraft models - particularly LSAs.
>
> That's true, and the biggest annoyance (of which I am aware) is that they
> have increased the recommended "idle" speed to increase the service life of
> the PSRU--which is of the spur gear type. I don't know whether any of the
> belt or chain type PSRU installations have a similar requirement.
>
> As to cooling: there were a lot of liquid cooled aircraft engines in WWII,
> but the the aircraft they in which they were installed looked a lot
> different from their air cooled counterparts.
>
> Peter

Even belted PSRUs have vibration nodes. The Glastar in which
we put a PSRU'd Soob didn't like 1400 engine RPM; it semed to be an
argument between the flywheel's inertia and the prop's. Running it at
that RPM for long would have torn the teeth off the belt. I didn't
notice if there were further nodes at 2800 and 5600. Adjusting belt
tension didn't change anything.
I've read about (and encountered) cases of cooling problems in
auto conversions. Many builders underestimate the amount of heat that
needs discarding, and also make mistakes in radiator installation and
baffling. I've seen rads mounted out in the breeze where they not only
slow the airplane but suffer from airflow problems created by the
vortices generated around the rad. I've seen a couple of small rads
mounted behine the front cowl openings, where they're supposed to get
ram air, but without proper baffling to separate the incoming air from
the air behind the rads the pressure differential is minimal, causing
low flow, and air eddying around the rad further interferes with
flow.
In the Glastar I mounted the big, full-size rad (from the same
car as the engine) behind the engine, at an angle so that the top edge
was at the firewall and the bottom was forward about 8". Baffling
around the rad made sure that ALL air leaving the cowl (except for a
bit leaving around the hot exhaust pipes) had to go through the rad,
so I had maximum flow. A lip on the cowl outlet to accelerate air away
from the opening lowered the pressure further so that max differential
was maintained between the front and rear of the rad. And even with
all this the engine's coolant temp reached max in an extended full-
power climb on a summer day.
The P-51 had an underbelly scoop and a variable-geometry outlet
behind it. The rad was in this housing. Inlet and outlet shape and
size were critical, and I've heard that the designers were so clever
that they even got a little thrust as the cooling air expanded and was
accelerated a little when it left the outlet. OWT, maybe, but there's
lots to learn from their design anyway. It's worth noting that the
inlet was much smaller than the rad's area; Mr. Bernoulli tells us
that pressure increases as airflow slows and decreases as it
accelerates, so the divergent duct between the inlet and rad face
slowed the air and increased its pressure. Same principle used in
numerous places in a jet engine.

Dan

[Bill Daniels]

> wrote in message
...
> On Aug 27, 3:32 pm, "Peter Dohm" > wrote:
>> "Jim Logajan" > wrote in message
>>
>> .. .
>>
>> > Ron Wanttaja > wrote:
>> >> On Tue, 26 Aug 2008 21:07:46 -0700 (PDT), "
>> >> > wrote:
>>
>> >>> everyone says "ooh -- auto...dangerous" but no
>> >>> one can explain exactly why.
>>
>> >> 1. Ignition systems with insufficient redundancy.
>> >> 2. PSRU failures.
>> >> 3. Difficulty in implementing efficient liquid cooling systems.
>>
>> > But doesn't the Rotax 912 have reduction gearing and liquid cooling? It
>> > is
>> > getting put into an awful lot of aircraft models - particularly LSAs.
>>
>> That's true, and the biggest annoyance (of which I am aware) is that they
>> have increased the recommended "idle" speed to increase the service life
>> of
>> the PSRU--which is of the spur gear type. I don't know whether any of
>> the
>> belt or chain type PSRU installations have a similar requirement.
>>
>> As to cooling: there were a lot of liquid cooled aircraft engines in
>> WWII,
>> but the the aircraft they in which they were installed looked a lot
>> different from their air cooled counterparts.
>>
>> Peter
>
> Even belted PSRUs have vibration nodes. The Glastar in which
> we put a PSRU'd Soob didn't like 1400 engine RPM; it semed to be an
> argument between the flywheel's inertia and the prop's. Running it at
> that RPM for long would have torn the teeth off the belt. I didn't
> notice if there were further nodes at 2800 and 5600. Adjusting belt
> tension didn't change anything.
> I've read about (and encountered) cases of cooling problems in
> auto conversions. Many builders underestimate the amount of heat that
> needs discarding, and also make mistakes in radiator installation and
> baffling. I've seen rads mounted out in the breeze where they not only
> slow the airplane but suffer from airflow problems created by the
> vortices generated around the rad. I've seen a couple of small rads
> mounted behine the front cowl openings, where they're supposed to get
> ram air, but without proper baffling to separate the incoming air from
> the air behind the rads the pressure differential is minimal, causing
> low flow, and air eddying around the rad further interferes with
> flow.
> In the Glastar I mounted the big, full-size rad (from the same
> car as the engine) behind the engine, at an angle so that the top edge
> was at the firewall and the bottom was forward about 8". Baffling
> around the rad made sure that ALL air leaving the cowl (except for a
> bit leaving around the hot exhaust pipes) had to go through the rad,
> so I had maximum flow. A lip on the cowl outlet to accelerate air away
> from the opening lowered the pressure further so that max differential
> was maintained between the front and rear of the rad. And even with
> all this the engine's coolant temp reached max in an extended full-
> power climb on a summer day.
> The P-51 had an underbelly scoop and a variable-geometry outlet
> behind it. The rad was in this housing. Inlet and outlet shape and
> size were critical, and I've heard that the designers were so clever
> that they even got a little thrust as the cooling air expanded and was
> accelerated a little when it left the outlet. OWT, maybe, but there's
> lots to learn from their design anyway. It's worth noting that the
> inlet was much smaller than the rad's area; Mr. Bernoulli tells us
> that pressure increases as airflow slows and decreases as it
> accelerates, so the divergent duct between the inlet and rad face
> slowed the air and increased its pressure. Same principle used in
> numerous places in a jet engine.
>
> Dan

Interesting post, Dan.

I've seen cylindrical "barrel" type heat exchangers intended for
installation in a round duct. I wonder if these might be an alternative
choice to the flat automotive-type radiators.

[[email protected]]

On Aug 26, 11:14*pm, Ron Wanttaja > wrote:
> On Tue, 26 Aug 2008 21:07:46 -0700 (PDT), "
>
> > wrote:
> > everyone says "ooh -- auto...dangerous" but no
> > one can explain exactly why.
>
> 1. Ignition systems with insufficient redundancy.
> 2. PSRU failures.
> 3. Difficulty in implementing efficient liquid cooling systems.
>
> Ron Wanttaja

i heard the e racer had an inflight engine fire and eventually the
designer through in the towl on auto engines. anyone remember why?

[Ron Wanttaja]

On Wed, 27 Aug 2008 16:11:51 -0500, Jim Logajan > wrote:

> Ron Wanttaja > wrote:
> > On Tue, 26 Aug 2008 21:07:46 -0700 (PDT), "
> > > wrote:
> >
> >> everyone says "ooh -- auto...dangerous" but no
> >> one can explain exactly why.
> >
> > 1. Ignition systems with insufficient redundancy.
> > 2. PSRU failures.
> > 3. Difficulty in implementing efficient liquid cooling systems.
>
> But doesn't the Rotax 912 have reduction gearing and liquid cooling? It is
> getting put into an awful lot of aircraft models - particularly LSAs.

Certainly, and my data shows that the Rotax 912, in homebuilts at least, has a
safety record pretty much equal to that of traditional certified engines.

My posting was an attempt to answer the OP's question on why some people believe
auto engine conversions are dangerous. The three items I mentioned are in the
top four causes of auto-engine failures. Looking at my 1998-2006 homebuilt
accident database and comparing fixed-wing applications, the rate of occurrence
of ignition system problems is four times higher for auto conversions than
traditional engines. And the traditional engines had no cases of PSRU or
cooling failure.

I believe it's possible to convert an auto engine and achieve reliabilities
equal to that of a traditional certified engine. It's just that the accident
reports show that many people can't achieve that goal. It's basically the same
people installing the Continentals as the Subarus, or the Rotax 912s and the
Fords. But the average builder seems to have less problems getting the Lyconts
and Rotaxen to be reliable.

Ron Wanttaja

[flybynightkarmarepair]

On Aug 27, 7:01*pm, "
> wrote:
> On Aug 26, 11:14*pm, Ron Wanttaja > wrote:
>
> > On Tue, 26 Aug 2008 21:07:46 -0700 (PDT), "
>
> > > wrote:
> > > everyone says "ooh -- auto...dangerous" but no
> > > one can explain exactly why.
>
> > 1. Ignition systems with insufficient redundancy.
> > 2. PSRU failures.
> > 3. Difficulty in implementing efficient liquid cooling systems.
>
> > Ron Wanttaja
>
> i heard the e racer had an inflight engine fire and eventually the
> designer through in the towl on auto engines. *anyone remember why?

Sure do.

"From: Dorothy Dickey
Sent: Monday, January 24, 2000 8:46 PM
To: Young, Ryan
Subject: Re: Engines for E-racers
There is nothing wrong with the Buick engine it's just that I no
longer favor
auto engines for aircraft applications. This is because it is not
possible
to achieve equivalent reliability and performance of an aircraft
engine for
the same or less money... So why do it? Shirl"

Remember, this is a guy who designed an airplane around an auto
conversion, and devoted serious time, money, and twice, almost his
life to making this idea work. If you think you can do better, step
right up.

This whole thread smacks of TROLL, but you can read what more of what
I think, along with the E-Racer guy (Shirl Dickey), and a little from
the Belted Air Power reduction guy (Jess Myers) here:

http://users.lmi.net/~ryoung/Sonerai/BOP.htm

You can also search this newsgroup for anything by Corky Scott, and
watch his chronicle. He never flew his auto engine conversion, after
working on it for years.

[Peter Dohm]

> wrote in message
...
> On Aug 27, 3:32 pm, "Peter Dohm" > wrote:
>> "Jim Logajan" > wrote in message
>>
>> .. .
>>
>> > Ron Wanttaja > wrote:
>> >> On Tue, 26 Aug 2008 21:07:46 -0700 (PDT), "
>> >> > wrote:
>>
>> >>> everyone says "ooh -- auto...dangerous" but no
>> >>> one can explain exactly why.
>>
>> >> 1. Ignition systems with insufficient redundancy.
>> >> 2. PSRU failures.
>> >> 3. Difficulty in implementing efficient liquid cooling systems.
>>
>> > But doesn't the Rotax 912 have reduction gearing and liquid cooling? It
>> > is
>> > getting put into an awful lot of aircraft models - particularly LSAs.
>>
>> That's true, and the biggest annoyance (of which I am aware) is that they
>> have increased the recommended "idle" speed to increase the service life
>> of
>> the PSRU--which is of the spur gear type. I don't know whether any of
>> the
>> belt or chain type PSRU installations have a similar requirement.
>>
>> As to cooling: there were a lot of liquid cooled aircraft engines in
>> WWII,
>> but the the aircraft they in which they were installed looked a lot
>> different from their air cooled counterparts.
>>
>> Peter
>
> Even belted PSRUs have vibration nodes. The Glastar in which
> we put a PSRU'd Soob didn't like 1400 engine RPM; it semed to be an
> argument between the flywheel's inertia and the prop's. Running it at
> that RPM for long would have torn the teeth off the belt. I didn't
> notice if there were further nodes at 2800 and 5600. Adjusting belt
> tension didn't change anything.
> I've read about (and encountered) cases of cooling problems in
> auto conversions. Many builders underestimate the amount of heat that
> needs discarding, and also make mistakes in radiator installation and
> baffling. I've seen rads mounted out in the breeze where they not only
> slow the airplane but suffer from airflow problems created by the
> vortices generated around the rad. I've seen a couple of small rads
> mounted behine the front cowl openings, where they're supposed to get
> ram air, but without proper baffling to separate the incoming air from
> the air behind the rads the pressure differential is minimal, causing
> low flow, and air eddying around the rad further interferes with
> flow.
> In the Glastar I mounted the big, full-size rad (from the same
> car as the engine) behind the engine, at an angle so that the top edge
> was at the firewall and the bottom was forward about 8". Baffling
> around the rad made sure that ALL air leaving the cowl (except for a
> bit leaving around the hot exhaust pipes) had to go through the rad,
> so I had maximum flow. A lip on the cowl outlet to accelerate air away
> from the opening lowered the pressure further so that max differential
> was maintained between the front and rear of the rad. And even with
> all this the engine's coolant temp reached max in an extended full-
> power climb on a summer day.
> The P-51 had an underbelly scoop and a variable-geometry outlet
> behind it. The rad was in this housing. Inlet and outlet shape and
> size were critical, and I've heard that the designers were so clever
> that they even got a little thrust as the cooling air expanded and was
> accelerated a little when it left the outlet. OWT, maybe, but there's
> lots to learn from their design anyway. It's worth noting that the
> inlet was much smaller than the rad's area; Mr. Bernoulli tells us
> that pressure increases as airflow slows and decreases as it
> accelerates, so the divergent duct between the inlet and rad face
> slowed the air and increased its pressure. Same principle used in
> numerous places in a jet engine.
>
> Dan
I was only thinking of the exact ratios that place the same teeth in use on
each successive rotation of the belt.

Torsional resonance can be extremely difficult to monitor andI am glad that
you were able to identify it before it became a dissaster. For the moment,
my own project and the decision to build around a PSRU or use a direct drive
aircraft engine has been pushed further into the future. But I have
wondered whether the elimination of critical speeds might be the true
purpose of those little springs in the driven plate of a manual clutch.

[Peter Dohm]

"flybynightkarmarepair" > wrote in message
...

FBNKR: This whole thread smacks of TROLL, but you can read what more of
what
I think, along with the E-Racer guy (Shirl Dickey), and a little from
the Belted Air Power reduction guy (Jess Myers) here:

Peter: I agree about the Troll, but sometimes one just can't resist...

FBNKR: http://users.lmi.net/~ryoung/Sonerai/BOP.htm

FBNKR: You can also search this newsgroup for anything by Corky Scott, and
watch his chronicle. He never flew his auto engine conversion, after
working on it for years.

Peter: I had wondered about what Corky finally did, but did recall that he
was giving up on the auto conversion idea--although IIRC his aircraft was a
four seater.

[Bill Daniels]

The problematic word in the subject of this thread is "simple".

An aluminum V8 auto-derived engine is not an aircraft engine - yet. It
needs a lot of engineering work to become one. If the engineering is well
done, the resulting aircraft engine will be successful. If it isn't.....
Many auto conversions weren't. It isn't easy.

Auto engines are high revving compared to direct drive aircraft engines so
to get a reasonable power to weight ratio, a PSRU is needed. But, isn't a
PSRU heavy? Yes, but so is the crankshaft of a direct drive engine - it has
to be to handle the torque. Auto engines have light cranks which are just
as strong on a HP to HP comparison since they rev higher. HP is just torque
(Ft Lbs) times RPM divided by 5252. Compare the weight of a direct drive
crank vs. the crank + PSRU weight of an auto conversion - not so much
difference as thought.

To minimize the re-engineering, keep the engine core working as nearly the
same as in a road vehicle but make sure it uses the best forged racing parts
like rods and pistons for durability. Use the lightest flywheel that allows
an even idle.

The PSRU is just a special PTO (Power Take Off) with gears. It mounts to
the flywheel housing and connects to the flywheel with a flex plate.
Millions of PTO's are in use as irrigation pumps so somebody knows how to do
it. It takes all the gyroscopic and thrust loads away from the crank which
'sees' no loads except torque. Make it from billet aluminum and use the
best bearing money can buy. I'd use a very close tolerance planetary
gearset for durability.

It will withstand high contineous power if you keep it cool. Design the
radiator for worst case cooling conditions and then control the airflow with
variable baffles. I'd feed a pair 12" diameter "barrel" radiators with jet
like wing root air intakes and rear fusalage exhaust . I'd augment the
radiator outflow with engine exhaust which keeps the radiator intakes from
ingesting hot engine exhaust while increasing airflow through the radiator.

I'd use 100PSI racing type fuel injection with in-tank pumps to prevent
vapor lock. I'd use closed loop mixture control with an O2 sensor. No
fussy carburator - no carb ice.

Would I put this thing in an airplane and fly it over the mountains at
night? Not at first - not by a long shot. I'd build it on a trailer so I
could run it in non-noise sensitive areas. I'd take it to air shows to
entertain but mainly I'd just run it on the trailer trying to break it. If
after a few years I still couldn't break it, then maybe in an airplane.
Ground testing is the expensive part. 2000 hours at 10GPH = 20,000 gallons
at $4 each = $80,000. Nobody said it was cheap.

[Morgans[_2_]]

"Bill Daniels" <bildan@comcast-dot-net> wrote

> I've seen cylindrical "barrel" type heat exchangers intended for
> installation in a round duct. I wonder if these might be an alternative
> choice to the flat automotive-type radiators.
>

Doubtful that you could get enough surface area in a round radiator. If you
just made it longer, efficiency would suffer, since the half that is
downstream would only be getting hot air.

Dan is absolutely correct, about the ducting and baffles being important.
In the P-51 (probably the best cooling design ever) the duct intake was
small, then the important part was the shape as the duct got bigger, to slow
the speed the air went through the radiator, and also like he said, gain a
little pressure.
--
Jim in NC

[Morgans[_2_]]

"Peter Dohm" > wrote

> Torsional resonance can be extremely difficult to monitor andI am glad
> that you were able to identify it before it became a dissaster. For the
> moment, my own project and the decision to build around a PSRU or use a
> direct drive aircraft engine has been pushed further into the future. But
> I have wondered whether the elimination of critical speeds might be the
> true purpose of those little springs in the driven plate of a manual
> clutch.

I have read about the issue of whether to have ratios to get a constantly
different belt to tooth interface, and I wish I could remember more of what
it said.

I recall that while it is important to vary ratios in a toothed gear redrive
away from exact ratios like 2:1, so different teeth mate with both gears
(prevents wearing a certain pattern in each other) that is not a necessary
condition for toothed belt redrives. I recall that in fact, it is not
desirable to do that, but again, my recall is incomplete.

The information is out there, though.

I would love to design my own belt redrive, but when the time comes, I know
I would be more comfortable going with a company that has a well proven
track record with many of their drives in active, high time service.
--
Jim in NC

[Morgans[_2_]]

"Bill Daniels" <bildan@comcast-dot-net> wrote

> Would I put this thing in an airplane and fly it over the mountains at
> night? Not at first - not by a long shot. I'd build it on a trailer so I
> could run it in non-noise sensitive areas. I'd take it to air shows to
> entertain but mainly I'd just run it on the trailer trying to break it.

How about putting on an airboat, and have fun, while trying to break it.
The chopping at the waves would put some gyroscopic loads on it that would
imitate, of even exceed the types of conditions that it would see on an
airplane, that you could not duplicate on a trailer.

I saw someone did that while developing a system, just recently. I plan to
do just that.

> If after a few years I still couldn't break it, then maybe in an airplane.
> Ground testing is the expensive part. 2000 hours at 10GPH = 20,000
> gallons at $4 each = $80,000. Nobody said it was cheap.

While I agree with the need to thouroughly test a unit, I do question the
need to do 2,000 hours, unless you are going for certification. Running it,
tearing it down occasionally and carefully inspecting (including
magnafluxing) will give you all the information you need for deciding
whether it is going to go the distance, IMHO.
--
Jim in NC

[[email protected]]

On Aug 28, 4:05 pm, "Morgans" > wrote:

> I recall that while it is important to vary ratios in a toothed gear redrive
> away from exact ratios like 2:1, so different teeth mate with both gears
> (prevents wearing a certain pattern in each other) that is not a necessary
> condition for toothed belt redrives. I recall that in fact, it is not
> desirable to do that, but again, my recall is incomplete.

Rotax two-strokes are available with a variety of gearbox
ratios, among them 2.0:1, 3.0:1 and 4.0:1. The others are odd, like
2.24:1 and 3.47:1. They've been building these things for a long time
and I expect they've figured out what the problems with even ratios
are and how to fix them.
http://www.rotax-aircraft-engines.com/downloadarea/503_447/techdata/Techn.Data_503.pdf
I have a Hummelbird that I want to get finished someday, and
I've considered the Rotax 503 for it. I don't like the rum-rum-rum
sound made by the odd ratios, and would choose an even number,
probably 3:1 or 4:1 so I could swing the largest prop possible for
better takeoff and climb performance.
The Hummelbird is supposed to use the half-VW, but after
Veeduber's advice about the VW's inadequate cylinder head finning and
its resulting propensity to burn its valves regularly, I think maybe
I'll stay away from it, even though I prefer the sound of a four-
stroke over the whine of a two-stroke. My first car was a VW Bug and
it burned its valves on a long uphill pull. It just wasn't made to put
out 100% power for any length of time.

Dan

[Ramsey]

"Peter Dohm" > wrote in message
. ..

> I was only thinking of the exact ratios that place the same teeth in use
> on each successive rotation of the belt.
>
> Torsional resonance can be extremely difficult to monitor andI am glad
> that you were able to identify it before it became a dissaster. For the
> moment, my own project and the decision to build around a PSRU or use a
> direct drive aircraft engine has been pushed further into the future. But
> I have wondered whether the elimination of critical speeds might be the
> true purpose of those little springs in the driven plate of a manual
> clutch.
>

I think their primary purpose it simply to reduce or eliminate chatter when
engaging the clutch. Most high performance clutches don't even use them.

[Ernest Christley]

Ramsey wrote:
> "Peter Dohm" > wrote in message
> . ..
>
>> I was only thinking of the exact ratios that place the same teeth in use
>> on each successive rotation of the belt.
>>
>> Torsional resonance can be extremely difficult to monitor andI am glad
>> that you were able to identify it before it became a dissaster. For the
>> moment, my own project and the decision to build around a PSRU or use a
>> direct drive aircraft engine has been pushed further into the future. But
>> I have wondered whether the elimination of critical speeds might be the
>> true purpose of those little springs in the driven plate of a manual
>> clutch.
>>
>
> I think their primary purpose it simply to reduce or eliminate chatter when
> engaging the clutch. Most high performance clutches don't even use them.
>
>
>


http://www.rotaryaviation.com/PSRU Zen Part 2.html

[[email protected]]

On Aug 27, 7:19*pm, flybynightkarmarepair > wrote:
> On Aug 27, 7:01*pm, "
>
>
>
>
>
> > wrote:
> > On Aug 26, 11:14*pm, Ron Wanttaja > wrote:
>
> > > On Tue, 26 Aug 2008 21:07:46 -0700 (PDT), "
>
> > > > wrote:
> > > > everyone says "ooh -- auto...dangerous" but no
> > > > one can explain exactly why.
>
> > > 1. Ignition systems with insufficient redundancy.
> > > 2. PSRU failures.
> > > 3. Difficulty in implementing efficient liquid cooling systems.
>
> > > Ron Wanttaja
>
> > i heard the e racer had an inflight engine fire and eventually the
> > designer through in the towl on auto engines. *anyone remember why?
>
> Sure do.
>
> "From: Dorothy Dickey
> Sent: Monday, January 24, 2000 8:46 PM
> To: Young, Ryan
> Subject: Re: Engines for E-racers
> There is nothing wrong with the Buick engine it's just that I no
> longer favor
> auto engines for aircraft applications. This is because it is not
> possible
> to achieve equivalent reliability and performance of an aircraft
> engine for
> the same or less money... So why do it? Shirl"
>
> Remember, this is a guy who designed an airplane around an auto
> conversion, and devoted serious time, money, and twice, almost his
> life to making this idea work. *If you think you can do better, step
> right up.
>
> This whole thread smacks of TROLL, but you can read what more of what
> I think, along with the E-Racer guy (Shirl Dickey), and a little from
> the Belted Air Power reduction guy (Jess Myers) here:
>
> http://users.lmi.net/~ryoung/Sonerai/BOP.htm
>
> You can also search this newsgroup for anything by Corky Scott, and
> watch his chronicle. *He never flew his auto engine conversion, after
> working on it for years.- Hide quoted text -
>
> - Show quoted text -

Sorry, but that quote does not say the specific technical reason(s) he
gave up, just the basic economic idea that i've already heard -- hence
the original post. I wanted to hear a really good reason to not use
an auto engine, give readily available magnetos. Someone eventually
said propellor loads on the auto crankshaft. Thanks to that person
for answering the question. It's time to look at the aircraft engines
again (maybe the Walters)... I don't have any other questions.

[Zebulon]

"Ernest Christley" > wrote in message
...
>
> http://www.rotaryaviation.com/PSRU Zen Part 2.html

Bad link.

[Charles Vincent]

Zebulon wrote:
> "Ernest Christley" > wrote in message
> ...
>> http://www.rotaryaviation.com/PSRU Zen Part 2.html
>
> Bad link.
>
>
>

The link is correct, you just have to use the whole thing.

<http://www.rotaryaviation.com/PSRU Zen Part 2.html>


Charles

[Zebulon]

"Zebulon" <@###@.^net> wrote in message
...
>
> "Ernest Christley" > wrote in message
> ...
>>
>> http://www.rotaryaviation.com/PSRU Zen Part 2.html
>
> Bad link.
>
>
>

Ok, got it now, but what's your point?

Is this what you are referring to?

"At this point it should be obvious that our original assumption about the
intended purpose of the damper is wrong. The engineers in Detroit are not
stupid and they don’t put in relatively expensive parts for no reason, so
why do manual transmission equipped cars have a damper? The main reason is
to absorb unexpected torque overloads. This happens only on rare occasions
like when someone gets overly aggressive with the throttle and suddenly
releases the clutch. The springs store the energy of the shock load and
release it in a more controlled fashion in order to avoid breaking
drive-train parts. "

[Peter Dohm]

"Zebulon" <@###@.^net> wrote in message
...
>
> "Zebulon" <@###@.^net> wrote in message
> ...
>>
>> "Ernest Christley" > wrote in message
>> ...
>>>
>>> http://www.rotaryaviation.com/PSRU Zen Part 2.html
>>
>> Bad link.
>>
>>
>>
>
> Ok, got it now, but what's your point?
>
> Is this what you are referring to?
>
> "At this point it should be obvious that our original assumption about the
> intended purpose of the damper is wrong. The engineers in Detroit are not
> stupid and they don't put in relatively expensive parts for no reason, so
> why do manual transmission equipped cars have a damper? The main reason
> is to absorb unexpected torque overloads. This happens only on rare
> occasions like when someone gets overly aggressive with the throttle and
> suddenly releases the clutch. The springs store the energy of the shock
> load and release it in a more controlled fashion in order to avoid
> breaking drive-train parts. "
>
>
>
The damper, which is indeed a relatively expensive part, is on the other end
of the engine and is intended to eliminate resonance within the engine. A
breif treatise, which probably started as an an internal document at one of
the big three auto makers, has been included on this forum a number of times
and is probably in an issue of Contact! Magazine as well; but I can't find a
copy on my current computer.

I could easily be incorrect about the purpose of the springs, but another
article from Contact! regarding the development of the BD-5 drive train
(which I also can not find) does provide some food for thought.

Peter

[[email protected]]

On Aug 31, 10:29 pm, "
> wrote:
> Sorry, but that quote does not say the specific technical reason(s) he
> gave up, just the basic economic idea that i've already heard -- hence
> the original post. I wanted to hear a really good reason to not use
> an auto engine, give readily available magnetos. Someone eventually
> said propellor loads on the auto crankshaft.

What? We didn't mention cooling issues, weight issues, PSRU issues,
cost issues or anything else? Aren't these good things to consider?

Dan

[Zebulon]

"Peter Dohm" > wrote in message
. ..
>>
> The damper, which is indeed a relatively expensive part, is on the other
> end of the engine and is intended to eliminate resonance within the
> engine. A breif treatise, which probably started as an an internal
> document at one of the big three auto makers, has been included on this
> forum a number of times and is probably in an issue of Contact! Magazine
> as well; but I can't find a copy on my current computer.
>
> I could easily be incorrect about the purpose of the springs, but another
> article from Contact! regarding the development of the BD-5 drive train
> (which I also can not find) does provide some food for thought.
>

I have seen the BD-5 article, and agree totally with it, and the article
referenced above. My only doubt is Detroit's intent when originally
implementing these spring mechanisms.

Years ago during my auto racing days, a custom clutch builder related to me,
that the springs served only to reduce or eliminate chatter during
engagement, and assist the smooth engagement of the clutch. Although I
didn't understand exactly how, especially at that time, I now suspect his
has a lot to do with resonance.

If the mechanisms were implemented to dampen shock loads during aggressive
driving, why would so many high performance clutch assemblies omit them?
They all seem to prefer solid clutch disks because these mechanisms are
prone to failure, especially in activities like drag racing.

Has anyone published actual tested results on the amount of torque required
to flex these mechanisms? Whatever it is, I would guess they would offer
little resistance to a V-8 crankshaft and steel flywheel assembly spinning
5000 to 8000 RPM, when someone dumps a clutch. I always assumed that's why
most of them have springs with a flat profile wire. It looks to me like the
springs are designed to be bottomed out regularly.

[Charles Vincent]

Zebulon wrote:
>
> Has anyone published actual tested results on the amount of torque required
> to flex these mechanisms? Whatever it is, I would guess they would offer
> little resistance to a V-8 crankshaft and steel flywheel assembly spinning
> 5000 to 8000 RPM, when someone dumps a clutch. I always assumed that's why
> most of them have springs with a flat profile wire. It looks to me like the
> springs are designed to be bottomed out regularly.
>
>

If you read the engineering texts you will find they are for reducing
shock loads and prevent gear chatter when idling or loafing around in
third gear on surface streets. Dan Horton who used to post hear did
measure them, though did not publish all of his data. They bottom out
well before the torque the engine is able to produce is reached, as you
would expect. In fact, I believe this is necessary to avoid a
longitudinal resonance during aggressive throttle changes.

Charles

[Charles Vincent]

wrote:
> On Aug 31, 10:29 pm, "
> > wrote:
>> Sorry, but that quote does not say the specific technical reason(s) he
>> gave up, just the basic economic idea that i've already heard -- hence
>> the original post. I wanted to hear a really good reason to not use
>> an auto engine, give readily available magnetos. Someone eventually
>> said propellor loads on the auto crankshaft.
>
> What? We didn't mention cooling issues, weight issues, PSRU issues,
> cost issues or anything else? Aren't these good things to consider?
>
> Dan


Guess you didn't know that the only thing holding back progress of the
auto engine in aviation was the availability of a hundred and twenty two
year old ignition design.

Charles

[[email protected]]

On Sep 3, 12:00*pm, Charles Vincent > wrote:
> wrote:
> > On Aug 31, 10:29 pm, "
> > > wrote:
> >> Sorry, but that quote does not say the specific technical reason(s) he
> >> gave up, just the basic economic idea that i've already heard -- hence
> >> the original post. *I wanted to hear a really good reason to not use
> >> an auto engine, give readily available magnetos. *Someone eventually
> >> said propellor loads on the auto crankshaft.
>
> > * What? We didn't mention cooling issues, weight issues, PSRU issues,
> > cost issues or anything else? Aren't these good things to consider?
>
> > * * * * Dan
>
> Guess you didn't know that the only thing holding back progress of the
> auto engine in aviation was the availability of a hundred and twenty two
> year old ignition design.
>
> Charles

Guess not. Now we can put a magneto on any old engine and go
flying! Considering that the magneto has a much higher failure rate
than the old battery point-and-condenser ignition, and therefore we
need two of them, I have no idea why, in this age of electronic
everything, the homebuilder market hasn't come up with a self-powered
electronic ignition module for conversions. It would look like a
magneto, and have the rotating magnet alternator to generate some
power, but wouldn't use the troublesome points or impulse couplings or
distributor and the alternator part would have many magnets, not just
one, so that the magneto dynamics that sometimes lead to drive failure
wouldn't be there. Dave Blanton found those dynamics in his
conversions and had to modify the mag drives to take it.

Dan

[[email protected]]

On Sep 3, 11:03*am, Charles Vincent > wrote:
> Zebulon wrote:
>
> > Has anyone published actual tested results on the amount of torque required
> > to flex these mechanisms? Whatever it is, I would guess they would offer
> > little resistance to a V-8 crankshaft and steel flywheel assembly spinning
> > 5000 to 8000 RPM, when someone dumps a clutch. I always assumed that's why
> > most of them have springs with a flat profile wire. It looks to me like the
> > springs are designed to be bottomed out regularly.
>
> If you read the engineering texts you will find they are for reducing
> shock loads and prevent gear chatter when idling or loafing around in
> third gear on surface streets. *Dan Horton who used to post hear did
> measure them, though did not publish all of his data. *They bottom out
> well before the torque the engine is able to produce is reached, as you
> would expect. *In fact, I believe this is necessary to avoid a
> longitudinal resonance during aggressive throttle changes.
>
> Charles

The reciprocating engine has power pulses, which the flywheel
is expected to damp out. That flywheel can't damp it all out, of
course, and so those springs will allow a bit of flex to minimize the
pulsations being transmitted to the drive train. In racing, component
life and smoothness are not prime concerns; strength and minimal
failure points are, so they're left out.

Dan

[Drew Dalgleish]

On Wed, 3 Sep 2008 11:12:15 -0700 (PDT),
wrote:


> Guess not. Now we can put a magneto on any old engine and go
>flying! Considering that the magneto has a much higher failure rate
>than the old battery point-and-condenser ignition, and therefore we
>need two of them, I have no idea why, in this age of electronic
>everything, the homebuilder market hasn't come up with a self-powered
>electronic ignition module for conversions. It would look like a
>magneto, and have the rotating magnet alternator to generate some
>power, but wouldn't use the troublesome points or impulse couplings or
>distributor and the alternator part would have many magnets, not just
>one, so that the magneto dynamics that sometimes lead to drive failure
>wouldn't be there. Dave Blanton found those dynamics in his
>conversions and had to modify the mag drives to take it.
>
> Dan

http://www.emagair.com/Index.htm

I have these on my lycoming and I think that it would be possible to
machine some kind of mount to fit it to an auto engine.

[[email protected]]

On Sep 3, 3:14*pm, (Drew Dalgleish)
wrote:
> On Wed, 3 Sep 2008 11:12:15 -0700 (PDT),
> wrote:
>
> > * * * * Guess not. Now we can put a magneto on any old engine and go
> >flying! Considering that the magneto has a much higher failure rate
> >than the old battery point-and-condenser ignition, and therefore we
> >need two of them, I have no idea why, in this age of electronic
> >everything, the homebuilder market hasn't come up with a self-powered
> >electronic ignition module for conversions. It would look like a
> >magneto, and have the rotating magnet alternator to generate some
> >power, but wouldn't use the troublesome points or impulse couplings or
> >distributor and the alternator part would have many magnets, not just
> >one, so that the magneto dynamics that sometimes lead to drive failure
> >wouldn't be there. Dave Blanton found those dynamics in his
> >conversions and had to modify the mag drives to take it.
>
> > * * * * Dan
>
> http://www.emagair.com/Index.htm
>
> I have these on my lycoming and *I think that it would be possible to
> machine some kind of mount to fit it to an auto engine.

Well. There it is! I wonder when they'll get certification?
I'd like to try a pair on one of our 172s to see if fuel economy and
performance are better. Should be, with variable timing.
The one drawback I can see: They use battery power, with a
built-in alternator in case the aircraft's electrics die. Without an
impulse coupleing, they wouldn't generate enough power for hand-
propping, so my old A-65 non-electric systemed Jodel is out of luck.
Dan

[Morgans[_2_]]

"Peter Dohm" > wrote

> The damper, which is indeed a relatively expensive part, is on the other
> end of the engine and is intended to eliminate resonance within the
> engine. A breif treatise, which probably started as an an internal
> document at one of the big three auto makers, has been included on this
> forum a number of times and is probably in an issue of Contact! Magazine
> as well; but I can't find a copy on my current computer.
>
> I could easily be incorrect about the purpose of the springs, but another
> article from Contact! regarding the development of the BD-5 drive train
> (which I also can not find) does provide some food for thought.

You are thinking of two different things.

The thing on the accessory end of the engine is the harmonic balancer, and
it does indeed dampen resonance in the crankshaft.

Dampeners also exist that go between the engine and the load, usually found
in industrial applications, or in marine applications.
--
Jim in NC

[Charles Vincent]

Drew Dalgleish wrote:
> On Wed, 3 Sep 2008 11:12:15 -0700 (PDT),
> wrote:
>
>
>> Guess not. Now we can put a magneto on any old engine and go
>> flying! Considering that the magneto has a much higher failure rate
>> than the old battery point-and-condenser ignition, and therefore we
>> need two of them, I have no idea why, in this age of electronic
>> everything, the homebuilder market hasn't come up with a self-powered
>> electronic ignition module for conversions. It would look like a
>> magneto, and have the rotating magnet alternator to generate some
>> power, but wouldn't use the troublesome points or impulse couplings or
>> distributor and the alternator part would have many magnets, not just
>> one, so that the magneto dynamics that sometimes lead to drive failure
>> wouldn't be there. Dave Blanton found those dynamics in his
>> conversions and had to modify the mag drives to take it.
>>
>> Dan
>
> http://www.emagair.com/Index.htm
>
> I have these on my lycoming and I think that it would be possible to
> machine some kind of mount to fit it to an auto engine.

Hot damn, now with an electronic ignition available, I can finally rip
that heavy water soaked v8 auto engine out of my truck and replace it
with a smooth running lycoming. After all, how hard could it be to
design a clutch and transmission adapter and effective cooling baffles
for idle to 60mph.

Charles

[Morgans[_2_]]

> wrote


Well. There it is! I wonder when they'll get certification?
I'd like to try a pair on one of our 172s to see if fuel economy and
performance are better. Should be, with variable timing.

The one drawback I can see: They use battery power, with a
built-in alternator in case the aircraft's electrics die. Without an
impulse coupleing, they wouldn't generate enough power for hand-
propping, so my old A-65 non-electric systemed Jodel is out of luck.

One of the models use a backup internal alternator, that should
power the units indefinitely, according to their information. It does need
800 RPM, though, but could be a "get-around" for that.

If you had a small gel cell 12 volt battery onboard, that would supply power
for starting and taxi operations, then switch off the battery, and it will
go to internal power.

With two self powered units onboard, the chances of both of them failing
would be less than both mags failing, I would think.

It would require a check on shut down, and start up, to verify both are
generating their own power.

With the battery shut off and 800 or more RPMs, turn off the starting power
battery, then cycle one unit then the other. If one of the units has
failed, you would know it.
--
Jim in NC

Anyone see a problem with that?

[Stuart & Kathryn Fields]

> wrote in message
...
On Sep 3, 3:14 pm, (Drew Dalgleish)
wrote:
> On Wed, 3 Sep 2008 11:12:15 -0700 (PDT),
> wrote:
>
> > Guess not. Now we can put a magneto on any old engine and go
> >flying! Considering that the magneto has a much higher failure rate
> >than the old battery point-and-condenser ignition, and therefore we
> >need two of them, I have no idea why, in this age of electronic
> >everything, the homebuilder market hasn't come up with a self-powered
> >electronic ignition module for conversions. It would look like a
> >magneto, and have the rotating magnet alternator to generate some
> >power, but wouldn't use the troublesome points or impulse couplings or
> >distributor and the alternator part would have many magnets, not just
> >one, so that the magneto dynamics that sometimes lead to drive failure
> >wouldn't be there. Dave Blanton found those dynamics in his
> >conversions and had to modify the mag drives to take it.
>
> > Dan
>
> http://www.emagair.com/Index.htm
>
> I have these on my lycoming and I think that it would be possible to
> machine some kind of mount to fit it to an auto engine.

Well. There it is! I wonder when they'll get certification?
I'd like to try a pair on one of our 172s to see if fuel economy and
performance are better. Should be, with variable timing.
The one drawback I can see: They use battery power, with a
built-in alternator in case the aircraft's electrics die. Without an
impulse coupleing, they wouldn't generate enough power for hand-
propping, so my old A-65 non-electric systemed Jodel is out of luck.
Dan
Dan: I've been flying a Lightspeed ignition on one side and a Slick mag on
the other on my Lycoming 0320 for several years. The only problem that I
have had is that with real low battery voltage, the timing can get wrong and
cause a kick back and damage the starter. As I understand it the newer
units have fixed this problem. Impulse coupling?? You don't need it. This
thing fires so much better than a magneto at any speed that mag checks,
turning the mag off gets no rpm drop and turning the Lightspeed off gets
about 100rpm drop. The spark coming off the light speed fed plug looks like
something from science fiction. Also I'm using automotive platinum plugs @
$4.50 each and the A/C equivalent would be about 10X that. A small
isolated battery takes care of a backup for electrical system failures. I
do not have one installed yet and it has been about 10 years now and have
never needed the back up.

[Peter Dohm]

"Morgans" > wrote in message
...
>
> "Peter Dohm" > wrote
>
>> The damper, which is indeed a relatively expensive part, is on the other
>> end of the engine and is intended to eliminate resonance within the
>> engine. A breif treatise, which probably started as an an internal
>> document at one of the big three auto makers, has been included on this
>> forum a number of times and is probably in an issue of Contact! Magazine
>> as well; but I can't find a copy on my current computer.
>>
>> I could easily be incorrect about the purpose of the springs, but another
>> article from Contact! regarding the development of the BD-5 drive train
>> (which I also can not find) does provide some food for thought.
>
> You are thinking of two different things.
>
> The thing on the accessory end of the engine is the harmonic balancer, and
> it does indeed dampen resonance in the crankshaft.
>
> Dampeners also exist that go between the engine and the load, usually
> found in industrial applications, or in marine applications.
> --
> Jim in NC
>
Very true, I had momentarily forgotten those. They would require some
mathematical analysis to specify correctly and I believe that Molt Taylor
may have used something of the sort on the IMP or Mini IMP. There are also
some so-called "dry fluid couplings" that I sort of understand, but not
completely.

Peter

[cavelamb himself[_4_]]

Peter Dohm wrote:

> "Morgans" > wrote in message
> ...
>
>>"Peter Dohm" > wrote
>>
>>
>>>The damper, which is indeed a relatively expensive part, is on the other
>>>end of the engine and is intended to eliminate resonance within the
>>>engine. A breif treatise, which probably started as an an internal
>>>document at one of the big three auto makers, has been included on this
>>>forum a number of times and is probably in an issue of Contact! Magazine
>>>as well; but I can't find a copy on my current computer.
>>>
>>>I could easily be incorrect about the purpose of the springs, but another
>>>article from Contact! regarding the development of the BD-5 drive train
>>>(which I also can not find) does provide some food for thought.
>>
>>You are thinking of two different things.
>>
>>The thing on the accessory end of the engine is the harmonic balancer, and
>>it does indeed dampen resonance in the crankshaft.
>>
>>Dampeners also exist that go between the engine and the load, usually
>>found in industrial applications, or in marine applications.
>>--
>>Jim in NC
>>
>
> Very true, I had momentarily forgotten those. They would require some
> mathematical analysis to specify correctly and I believe that Molt Taylor
> may have used something of the sort on the IMP or Mini IMP. There are also
> some so-called "dry fluid couplings" that I sort of understand, but not
> completely.
>
> Peter
>
>


A coupling consisting of a pair of "wavy" plates and a dry fluid (like
bird shot) that does the actual connecting.

IIRC, it was adapted from an early automotive "automatic clutch" ??

--

Richard

(remove the X to email)

[Peter Dohm]

"cavelamb himself" > wrote in message
m...
> Peter Dohm wrote:
>
>> "Morgans" > wrote in message
>> ...
>>
>>>"Peter Dohm" > wrote
>>>
>>>
>>>>The damper, which is indeed a relatively expensive part, is on the other
>>>>end of the engine and is intended to eliminate resonance within the
>>>>engine. A breif treatise, which probably started as an an internal
>>>>document at one of the big three auto makers, has been included on this
>>>>forum a number of times and is probably in an issue of Contact! Magazine
>>>>as well; but I can't find a copy on my current computer.
>>>>
>>>>I could easily be incorrect about the purpose of the springs, but
>>>>another article from Contact! regarding the development of the BD-5
>>>>drive train (which I also can not find) does provide some food for
>>>>thought.
>>>
>>>You are thinking of two different things.
>>>
>>>The thing on the accessory end of the engine is the harmonic balancer,
>>>and it does indeed dampen resonance in the crankshaft.
>>>
>>>Dampeners also exist that go between the engine and the load, usually
>>>found in industrial applications, or in marine applications.
>>>--
>>>Jim in NC
>>>
>>
>> Very true, I had momentarily forgotten those. They would require some
>> mathematical analysis to specify correctly and I believe that Molt Taylor
>> may have used something of the sort on the IMP or Mini IMP. There are
>> also some so-called "dry fluid couplings" that I sort of understand, but
>> not completely.
>>
>> Peter
>
>
> A coupling consisting of a pair of "wavy" plates and a dry fluid (like
> bird shot) that does the actual connecting.
>
> IIRC, it was adapted from an early automotive "automatic clutch" ??
>
> --
>
> Richard
>
I remembered that he used the Flexidyne coupling, essentially a centrifugal
clutch, in that little twin engine machine with a single prop; but had
forgotten what he used in the IMP series. It centainly would have been a
valid cure for the BD-5 problems, which occured at or below idle speed, as
well. Apparently, it is most commonly used for industrial applications of
electric motors and here is a link to a product description:
http://www.dodge-pt.com/products/pt_components/flexidyne/flexidyne.html

Peter

[Barnyard BOb]

On Thu, 28 Aug 2008 18:18:08 -0400, "Morgans"
> wrote:

>
>"Bill Daniels" <bildan@comcast-dot-net> wrote
>
>> If after a few years I still couldn't break it, then maybe in an airplane.
>> Ground testing is the expensive part. 2000 hours at 10GPH = 20,000
>> gallons at $4 each = $80,000. Nobody said it was cheap.
>
>While I agree with the need to thouroughly test a unit, I do question the
>need to do 2,000 hours, unless you are going for certification. Running it,
>tearing it down occasionally and carefully inspecting (including
>magnafluxing) will give you all the information you need for deciding
>whether it is going to go the distance, IMHO.

-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-

Morgans.
You never fail to amaze! ;-)

You know so much....


- NOT -


- Barnyard BOb -

The more people I meet,
the more I like my dog
and George Carlin humor.

May he now rest in peace.

[stol]

On Sep 5, 4:49*am, Barnyard BOb > wrote:
> On Thu, 28 Aug 2008 18:18:08 -0400, "Morgans"
>
> > wrote:
>
> >"Bill Daniels" <bildan@comcast-dot-net> wrote
>
> >> If after a few years I still couldn't break it, then maybe in an airplane.
> >> Ground testing is the expensive part. *2000 hours at 10GPH = 20,000
> >> gallons at $4 each = $80,000. *Nobody said it was cheap.
>
> >While I agree with the need to thouroughly test a unit, I do question the
> >need to do 2,000 hours, unless you are going for certification. *Running it,
> >tearing it down occasionally and carefully inspecting (including
> >magnafluxing) will give you all the information you need for deciding
> >whether it is going to go the distance, IMHO.
>
> -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
>
> Morgans.
> You never fail to amaze! *;-)
>
> You know so much....
>
> * * * - NOT -
>
> - Barnyard BOb -
>
> The more people I meet,
> the more I like my dog
> and George Carlin humor.
>
> May he now rest in peace.

This is the Rec. Aviation. HOMEBUILT group. Feel free to wander over
to the Rec. Aviation. CERTIFIED group to voice your concerns. You
really need to be addressing the correct group to get any respect..

Tailwinds.

Ben
www.haaspowerair.com

[Barnyard BOb]

On Fri, 5 Sep 2008 06:24:52 -0700 (PDT), stol >
wrote:

>> Morgans.
>> You never fail to amaze! *;-)
>>
>> You know so much....
>>
>> * * * - NOT -
>>
>> - Barnyard BOb -
>>
>> The more people I meet,
>> the more I like my dog
>> and George Carlin humor.
>>
>> May he now rest in peace.
>
>This is the Rec. Aviation. HOMEBUILT group. Feel free to wander over
>to the Rec. Aviation. CERTIFIED group to voice your concerns. You
>really need to be addressing the correct group to get any respect..
>
>Tailwinds.
>
>Ben

-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-

Unless your name is Morgans...

** PHUCK OFF **

Get a life... and sense of humor!



- Barnyard BOb -

[Morgans[_2_]]

"Barnyard BOb" > wrote

> Unless your name is Morgans...
>
> ** PHUCK OFF **
>
> Get a life... and sense of humor!

Uhhh, Bob?

As you always seemed to like correcting my speeling errarhs, I need to point
out that you spelled "PHUCK" wrong.

You seem to think this word is like a phone, somehow? <gg>
--
Jim in NC