Corvair conversion engines

"Peter Dohm" wrote in message
news
---------much snipped-----------


These were also 40 year old cranks of unknown provenence, pulled out
of old car engines that may have been thrashed to within an inch of
their lives in previous "inCARnations"

This has been my area of concern as well. I would really find these
engines more attractive if I was confident that a complete new engine
could
be built.

New engines don't have crankshaft problems?

BWAHAHAHAHAHAHA!!!

Rich S.

"Rich S." wrote in message
...
"Peter Dohm" wrote in message
news
---------much snipped-----------


These were also 40 year old cranks of unknown provenence, pulled out
of old car engines that may have been thrashed to within an inch of
their lives in previous "inCARnations"

This has been my area of concern as well. I would really find these
engines more attractive if I was confident that a complete new engine
could
be built.

New engines don't have crankshaft problems?

BWAHAHAHAHAHAHA!!!

Rich S.

Yes. I know that they do, and new design engines are notorious; as are
design improvements, changes of supplier, etc. And they include plenty of
reasons for loss of power not caused by the crankshaft!

However, my concerns include, reliability, maintainability, and eventual
replacement; and I think you understand my point.

At this point, the Jabiru 3300 is the only engine that really looks to me
like a promising replacement; and I really don't know its service record.
However, albeit at a higher dollar price, its features seem to preserve: 1)
similar or lighter weight, 2) similar or higher power, 3) six cylinder
smoothness, 4) reasonably slow idle, and 5) similar dimmensions. Additional
benefits are designed in dual ignition and an updraft intake system, similar
to Lycoming and Continental, which should be more resistant to ice.

Peter

"Peter Dohm" wrote in message
...
Yes. I know that they do, and new design engines are notorious; as are
design improvements, changes of supplier, etc. And they include plenty of
reasons for loss of power not caused by the crankshaft!

However, my concerns include, reliability, maintainability, and eventual
replacement; and I think you understand my point.

At this point, the Jabiru 3300 is the only engine that really looks to me
like a promising replacement; and I really don't know its service record.
However, albeit at a higher dollar price, its features seem to preserve:
1)
similar or lighter weight, 2) similar or higher power, 3) six cylinder
smoothness, 4) reasonably slow idle, and 5) similar dimmensions.
Additional
benefits are designed in dual ignition and an updraft intake system,
similar
to Lycoming and Continental, which should be more resistant to ice.

Peter..........

Since you answered seriously, I will too. I can agree on the higher price
and on #1-3 and #5. I don't understand #4 - do Corvairs idle unreasonably
high? The dual ignition is good if the Jabiru 3300 truly has two stand-alone
systems. The intake direction is irrelevant if the Corvair is fuel-injected
or has a heated intake manifold. Updraft carbs are a lot better at
preventing fire as well. The small Continentals will ice up if you look at
them cross-eyed even with updraft intake.

Rich S.

"Rich S." wrote in message
. ..
"Peter Dohm" wrote in message
...
Yes. I know that they do, and new design engines are notorious; as are
design improvements, changes of supplier, etc. And they include plenty
of
reasons for loss of power not caused by the crankshaft!

However, my concerns include, reliability, maintainability, and eventual
replacement; and I think you understand my point.

At this point, the Jabiru 3300 is the only engine that really looks to
me
like a promising replacement; and I really don't know its service
record.
However, albeit at a higher dollar price, its features seem to preserve:
1)
similar or lighter weight, 2) similar or higher power, 3) six cylinder
smoothness, 4) reasonably slow idle, and 5) similar dimmensions.
Additional
benefits are designed in dual ignition and an updraft intake system,
similar
to Lycoming and Continental, which should be more resistant to ice.

Peter..........

Since you answered seriously, I will too. I can agree on the higher price
and on #1-3 and #5. I don't understand #4 - do Corvairs idle unreasonably
high? The dual ignition is good if the Jabiru 3300 truly has two
stand-alone
systems. The intake direction is irrelevant if the Corvair is
fuel-injected
or has a heated intake manifold. Updraft carbs are a lot better at
preventing fire as well. The small Continentals will ice up if you look at
them cross-eyed even with updraft intake.

Rich S.


The Corvairs have a very good idle. But the Rotax, which is one of the
possible replacements I would include on my list, seems to have a minimum
operating speed restriction. On a KR-2, which has no flaps, I suspect it
would result in very flat final approaches.

You are right about the small Contintals, time has gone by and I just plain
forgot.

Peter Dohm wrote:

The Corvairs have a very good idle. But the Rotax, which is one of the
possible replacements I would include on my list, seems to have a minimum
operating speed restriction. On a KR-2, which has no flaps, I suspect it
would result in very flat final approaches.

You are right about the small Contintals, time has gone by and I just
plain forgot.

The KR-2 built to plans do have flaps. The drawings are hanging on the wall
behind me;-)
John

wish I could unload it so I could get/build a SP elegible aircraft!

"UltraJohn" wrote in message
nk.net...
Peter Dohm wrote:

The Corvairs have a very good idle. But the Rotax, which is one of the
possible replacements I would include on my list, seems to have a
minimum
operating speed restriction. On a KR-2, which has no flaps, I suspect
it
would result in very flat final approaches.

You are right about the small Contintals, time has gone by and I just
plain forgot.

The KR-2 built to plans do have flaps. The drawings are hanging on the
wall
behind me;-)
John

wish I could unload it so I could get/build a SP elegible aircraft!

Oops! You're right. The plans are rolled in a tube, but I verified it in
the book.

Peter

Rich S. wrote:
"Peter Dohm" wrote in message
...

Yes. I know that they do, and new design engines are notorious; as are
design improvements, changes of supplier, etc. And they include plenty of
reasons for loss of power not caused by the crankshaft!

However, my concerns include, reliability, maintainability, and eventual
replacement; and I think you understand my point.

At this point, the Jabiru 3300 is the only engine that really looks to me
like a promising replacement; and I really don't know its service record.
However, albeit at a higher dollar price, its features seem to preserve:
1)
similar or lighter weight, 2) similar or higher power, 3) six cylinder
smoothness, 4) reasonably slow idle, and 5) similar dimmensions.
Additional
benefits are designed in dual ignition and an updraft intake system,
similar
to Lycoming and Continental, which should be more resistant to ice.


Peter..........

Since you answered seriously, I will too. I can agree on the higher price
and on #1-3 and #5. I don't understand #4 - do Corvairs idle unreasonably
high? The dual ignition is good if the Jabiru 3300 truly has two stand-alone
systems. The intake direction is irrelevant if the Corvair is fuel-injected
or has a heated intake manifold. Updraft carbs are a lot better at
preventing fire as well. The small Continentals will ice up if you look at
them cross-eyed even with updraft intake.

Rich S.



The Lycoming approach, with the intake manifolds passing through the oil
sump are less inclined to ice up. I'm sure they can be provoked, though.

As for the Corvair's idle? I plain dunno.
I have never seen a Corvair on an airplane - in person.
ANd that kinda is the point here.

The mounted pics I have seen are on a Pietenpol Air Camper, which needs
the weight on the nose. On most other planes that's considered a
Bad Thing (tm). On small short coupled airplanes, it might qualify as
a Very Bad Thing (tm), which is obviously much worse.

Now, I've only *seen* the Jabaru on a plane.
Haven't flown one myself.
But it does look like an engine of fine merit.

Light and simple are high on my short list.

Cost is there too, of course, but it has to take a place in line with
the rest of the conflicting requirements.

The Rotax 912 (which I have flown) is a really sweet set-up.
There is the extra complication (and weight) of the liquid cooled heads.
But it's probably not that big a deal on any two-seater.

From what I've heard, the Jabaru/912 power ratings remind me of the old
Continental A-65/Lycoming 145 days. Both were rated at 65 hp, but the
Continental horses seem a little longer legged.

I'd rank most VW power estimates as Shetland ponies...
I suspect that most people expect a VW to put out like a Rotax, but it
just doesn't work that way.

In the end the final choice will depend on the airframe and the mission.


On the Corvair question...

As I said earlier the Great Plains crank on my 2180 i.e. a way massive
hunk of pure confidence. Just the way an A-65 crank compares to other
small 4 banger non-flying counterparts.

So, why can't someone turn out a new Corvair crank - built to aircraft
service requirements?

The Corvair engine is a 4 bearing block, isn't it?

There is no reason that you _have_ to have a Corvair crank is there?


Richard

Rich,

Whatchit with that BWHAAAAAAaaaaa stuff.
Scared the stuffings outta me.

O thought Badwater was back and I was going to have to spell check my
posts...

On Tue, 24 Jan 2006 22:10:02 GMT, Richard Lamb
wrote:

Rich S. wrote:
"Peter Dohm" wrote in message
...

Yes. I know that they do, and new design engines are notorious; as are
design improvements, changes of supplier, etc. And they include plenty of
reasons for loss of power not caused by the crankshaft!

However, my concerns include, reliability, maintainability, and eventual
replacement; and I think you understand my point.

At this point, the Jabiru 3300 is the only engine that really looks to me
like a promising replacement; and I really don't know its service record.
However, albeit at a higher dollar price, its features seem to preserve:
1)
similar or lighter weight, 2) similar or higher power, 3) six cylinder
smoothness, 4) reasonably slow idle, and 5) similar dimmensions.
Additional
benefits are designed in dual ignition and an updraft intake system,
similar
to Lycoming and Continental, which should be more resistant to ice.


Peter..........

Since you answered seriously, I will too. I can agree on the higher price
and on #1-3 and #5. I don't understand #4 - do Corvairs idle unreasonably
high? The dual ignition is good if the Jabiru 3300 truly has two stand-alone
systems. The intake direction is irrelevant if the Corvair is fuel-injected
or has a heated intake manifold. Updraft carbs are a lot better at
preventing fire as well. The small Continentals will ice up if you look at
them cross-eyed even with updraft intake.

Rich S.



The Lycoming approach, with the intake manifolds passing through the oil
sump are less inclined to ice up. I'm sure they can be provoked, though.

As for the Corvair's idle? I plain dunno.
I have never seen a Corvair on an airplane - in person.
ANd that kinda is the point here.

The mounted pics I have seen are on a Pietenpol Air Camper, which needs
the weight on the nose. On most other planes that's considered a
Bad Thing (tm). On small short coupled airplanes, it might qualify as
a Very Bad Thing (tm), which is obviously much worse.

Now, I've only *seen* the Jabaru on a plane.
Haven't flown one myself.
But it does look like an engine of fine merit.

Light and simple are high on my short list.

Cost is there too, of course, but it has to take a place in line with
the rest of the conflicting requirements.

The Rotax 912 (which I have flown) is a really sweet set-up.
There is the extra complication (and weight) of the liquid cooled heads.
But it's probably not that big a deal on any two-seater.

From what I've heard, the Jabaru/912 power ratings remind me of the old
Continental A-65/Lycoming 145 days. Both were rated at 65 hp, but the
Continental horses seem a little longer legged.

I'd rank most VW power estimates as Shetland ponies...
I suspect that most people expect a VW to put out like a Rotax, but it
just doesn't work that way.

In the end the final choice will depend on the airframe and the mission.


On the Corvair question...

As I said earlier the Great Plains crank on my 2180 i.e. a way massive
hunk of pure confidence. Just the way an A-65 crank compares to other
small 4 banger non-flying counterparts.

So, why can't someone turn out a new Corvair crank - built to aircraft
service requirements?

The Corvair engine is a 4 bearing block, isn't it?

There is no reason that you _have_ to have a Corvair crank is there?


Richard

Rich,

Whatchit with that BWHAAAAAAaaaaa stuff.
Scared the stuffings outta me.

O thought Badwater was back and I was going to have to spell check my
posts...


Got ten grand? You can have a "proper" crank made - or for 300 grand
you can have a hundred of them.
As for the idle, mine ticked over very nicely at 700 RPM with a 72
inch IVO Magnum - but the Magnum was too much prop and was only able
to spin about 2450 or so. It idles fine at 750 with a 3 bladr 68" Ivo
ultralight - which is not enough prop and can be spun over 3000 at
full pitch.

"Richard Lamb" wrote in message
link.net...
Rich S. wrote:
"Peter Dohm" wrote in message
...

Yes. I know that they do, and new design engines are notorious; as are
design improvements, changes of supplier, etc. And they include plenty
of
reasons for loss of power not caused by the crankshaft!

However, my concerns include, reliability, maintainability, and eventual
replacement; and I think you understand my point.

At this point, the Jabiru 3300 is the only engine that really looks to
me
like a promising replacement; and I really don't know its service
record.
However, albeit at a higher dollar price, its features seem to preserve:
1)
similar or lighter weight, 2) similar or higher power, 3) six cylinder
smoothness, 4) reasonably slow idle, and 5) similar dimmensions.
Additional
benefits are designed in dual ignition and an updraft intake system,
similar
to Lycoming and Continental, which should be more resistant to ice.


Peter..........

Since you answered seriously, I will too. I can agree on the higher
price
and on #1-3 and #5. I don't understand #4 - do Corvairs idle
unreasonably
high? The dual ignition is good if the Jabiru 3300 truly has two
stand-alone
systems. The intake direction is irrelevant if the Corvair is
fuel-injected
or has a heated intake manifold. Updraft carbs are a lot better at
preventing fire as well. The small Continentals will ice up if you look
at
them cross-eyed even with updraft intake.

Rich S.



The Lycoming approach, with the intake manifolds passing through the oil
sump are less inclined to ice up. I'm sure they can be provoked, though.

As for the Corvair's idle? I plain dunno.
I have never seen a Corvair on an airplane - in person.
ANd that kinda is the point here.

The mounted pics I have seen are on a Pietenpol Air Camper, which needs
the weight on the nose. On most other planes that's considered a
Bad Thing (tm). On small short coupled airplanes, it might qualify as
a Very Bad Thing (tm), which is obviously much worse.

Now, I've only *seen* the Jabaru on a plane.
Haven't flown one myself.
But it does look like an engine of fine merit.

Light and simple are high on my short list.

Cost is there too, of course, but it has to take a place in line with
the rest of the conflicting requirements.

The Rotax 912 (which I have flown) is a really sweet set-up.
There is the extra complication (and weight) of the liquid cooled heads.
But it's probably not that big a deal on any two-seater.

From what I've heard, the Jabaru/912 power ratings remind me of the old
Continental A-65/Lycoming 145 days. Both were rated at 65 hp, but the
Continental horses seem a little longer legged.

I'd rank most VW power estimates as Shetland ponies...
I suspect that most people expect a VW to put out like a Rotax, but it
just doesn't work that way.

In the end the final choice will depend on the airframe and the mission.


On the Corvair question...

As I said earlier the Great Plains crank on my 2180 i.e. a way massive
hunk of pure confidence. Just the way an A-65 crank compares to other
small 4 banger non-flying counterparts.

So, why can't someone turn out a new Corvair crank - built to aircraft
service requirements?

The Corvair engine is a 4 bearing block, isn't it?

There is no reason that you _have_ to have a Corvair crank is there?


Richard

Rich,

Whatchit with that BWHAAAAAAaaaaa stuff.
Scared the stuffings outta me.

O thought Badwater was back and I was going to have to spell check my
posts...

I believe that you are correct on all of your points.

The only thing that I really feel compelled to add is that, in the case of
the KR that had a complete crankshaft failure and was "substantially
damaged", the owner had been very agressive in his program to keep the
weight down. I believe that he told me it was less than 200# firewall
forward, which may have even been a record. Even presuming that the weight
excluded the cowling, that is very light, and I have no idea how harmonic
damping was accomplished on any of these engines.

Peter

On Tue, 24 Jan 2006 13:32:22 -0800, "Rich S."
wrote:

"Peter Dohm" wrote in message
...
Yes. I know that they do, and new design engines are notorious; as are
design improvements, changes of supplier, etc. And they include plenty of
reasons for loss of power not caused by the crankshaft!

However, my concerns include, reliability, maintainability, and eventual
replacement; and I think you understand my point.

At this point, the Jabiru 3300 is the only engine that really looks to me
like a promising replacement; and I really don't know its service record.
However, albeit at a higher dollar price, its features seem to preserve:
1)
similar or lighter weight, 2) similar or higher power, 3) six cylinder
smoothness, 4) reasonably slow idle, and 5) similar dimmensions.
Additional
benefits are designed in dual ignition and an updraft intake system,
similar
to Lycoming and Continental, which should be more resistant to ice.

Peter..........

Since you answered seriously, I will too. I can agree on the higher price
and on #1-3 and #5. I don't understand #4 - do Corvairs idle unreasonably
high? The dual ignition is good if the Jabiru 3300 truly has two stand-alone
systems. The intake direction is irrelevant if the Corvair is fuel-injected
or has a heated intake manifold. Updraft carbs are a lot better at
preventing fire as well. The small Continentals will ice up if you look at
them cross-eyed even with updraft intake.

Rich S.

And updraft carbs are NO LESS dangerous firewise. They can't leak on
the top of the hot engine (but a properly designed top carb can't
either) but they have over a yard of "wet" intake manifold - if or
when the (flooded) engine backfires when starting and the battery is
low, a bottom carb engine WILL BURN.