Today's Message Index:
----------------------
1. 12:11 AM - Highlight Two (Matt Dralle)
2. 04:27 AM - Re: Engine Choices (LarryRobertHelming)
3. 06:16 AM - Re: Engine Choices (Frank Stringham)
4. 07:06 AM - Re: Engine Choices (Hinde, Frank George (Corvallis))
5. 07:22 AM - Re: Engine Choices (Hinde, Frank George (Corvallis))
6. 08:46 AM - Re: Engine Choices (Rob Prior (rv7))
7. 09:34 AM - Re: Engine Choices (Hinde, Frank George (Corvallis))
8. 10:19 AM - Re: Engine Choices (Rob Prior (rv7))
9. 04:35 PM - Re: Engine Choices (Dan Checkoway)
10. 04:52 PM - Re: Engine Choices (Hinde, Frank George (Corvallis))
11. 05:59 PM - Re: Engine Choices (Tyler Bryant)
Message 1
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--> RV7-List message posted by: Matt Dralle <dralle@matronics.com>
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do not archive
Message 2
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| Subject: | Re: Engine Choices |
Peter, One thing to consider is the value of your plane after it is done. And
also if you have a problem while flying cross country and have to land some place
unfamiliar. Airports across the country are equipped with mechanics that
look at Lycoming type engines all the time, a subby maybe not. The subby has
more possible failure modes that is for sure. Only one spark plug per cylinder,
for example. That engine will not keep you climbing if it starts running on
just 3. Consider where you are flying most of the time and whether climbing
is vital to your safety. Reading the Eggenfeltner email is a good thing to do.
They are still discovering new things it seems every month (although I have
not read it lately). I went this same route three years ago and even ordered
a subby at one point. I like the features and ability of the subby but decided
that the proven Lycoming type was better for me. In the end, I just decided
I really did not want to be a test pilot for Jan. Jan was very fair with me
all the way. I like him. I have a friend who is almost ready to start flying
his RV6A with Eggenfeltner subby. His installation looks more compact/complicated
and totally packed in there than a Lycoming type. Working on it going
forward seems like it will be a concern. You cannot get to anything without
moving something else out of the way it seems. However, It sounds great and runs
smoothly on the ground. Keep in mind It was not designed for putting out
80 percent power at 3,500 rpm as it will be doing in the air. Jan says no one
has met the TBO yet. I wish he would run one to that point and know the answer!
(The longest running engine of his still has only about 1,000 hours on it
and at that point, it is not a value yet). Although he thought so getting into
it, I am not sure my friend's total cost is any cheaper than something like
a TMX-O360. If you must have fuel injection in the Lycoming type, that is more
of course and you got that with the subby. With my TMX engine, I can burn
92 octane unleaded after 200 hours. It is good you are looking into this early.
Lots of stuff to consider and most folks have a slightly different slant
on priorities and risk.
I recommend you visit Jan's place of business if you can make a trip out of it.
I think a guy named Morris visited Jan about 3-4 years ago. It might be in
the RV7-List archives or the RV-List archives. His posting influenced my decision.
But all things change -- and as I said, I like the features of the subby
engine. AND -- I'd talk with Vans before deciding on a 390. Best wishes.
Indiana Larry
----- Original Message -----
From: Peter Lythall
To: rv7-list@matronics.com
Sent: Wednesday, November 16, 2005 12:52 AM
Subject: RV7-List: Engine Choices
Hello,
Snip.......Now I need to decide on what powerplant in hang on the front end of
this thing and I am torn between a couple of choices. I am looking for some
input from other builders who have researched and/or installed the Subaru H-6
engine.
At this juncture I am looking at either the io-360(tried and true) or the Eggenfellner
H-6(looks sharp and if packed with new type technology, water cooled,
lower op costs, lower tbo costs, and burns mogas and 100ll). Another option
is the new io-390 but I haven't really looked at that. So any comments on the
soob. I have discussed with various folks including a local AME (great guy) and
various pilots at the hanger that I often show up for coffee at. I have watched
the eggenfellner yahoo list but I am still not entirely certain. So I am looking
for some totally biased input. If you have installed one of these beasts
or can direct me to some unhappy or happy owners that would be fantastic.
Peter Lythall
Fort St. John, BC Canada
Message 3
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--> RV7-List message posted by: "Frank Stringham" <fstringham@hotmail.com>
Peter
Check out www.attawayair.com (robbie attaway) for info on the IO360 and
http://brian76.mystarband.net/rv7a/RV-7Ahome.htm (Brian Meyette) on the
Subaru. I was at you juncture about 6 months ago and these two sites and
calls to Robbie helped me make my choice.
Frank @ SGU and SLC.......fuse about done on to finish.............
>From: "Peter Lythall" <peter@nortech.bc.ca>
>Reply-To: rv7-list@matronics.com
>To: <rv7-list@matronics.com>
>Subject: RV7-List: Engine Choices
>Date: Tue, 15 Nov 2005 23:52:49 -0700
>
>Hello,
>
>
>I am working on my RV7 Empennage and have ordered my qb to pickup in mid
>January. Now I want to minimize the shipping costs and I am going to
>pickup
>the QB kit at Vans's. It will give me a nice break from work and we can
>visit the inlaws on the way (what fun). Now I need to decide on what
>powerplant in hang on the front end of this thing and I am torn between a
>couple of choices. I am looking for some input from other builders who have
>researched and/or installed the Subaru H-6 engine.
>
>
>At this juncture I am looking at either the io-360(tried and true) or the
>Eggenfellner H-6(looks sharp and if packed with new type technology, water
>cooled, lower op costs, lower tbo costs, and burns mogas and 100ll).
>Another
>option is the new io-390 but I haven't really looked at that. So any
>comments on the soob. I have discussed with various folks including a local
>AME (great guy) and various pilots at the hanger that I often show up for
>coffee at. I have watched the eggenfellner yahoo list but I am still not
>entirely certain. So I am looking for some totally biased input. If you
>have
>installed one of these beasts or can direct me to some unhappy or happy
>owners that would be fantastic.
>
>
>Peter Lythall
>
>
>Fort St. John, BC Canada
>
Message 4
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Why mogas after 200 hours Larry?...I was working more on 50...
Thanks
Frank
________________________________
From: owner-rv7-list-server@matronics.com
[mailto:owner-rv7-list-server@matronics.com] On Behalf Of
LarryRobertHelming
Subject: Re: RV7-List: Engine Choices
Peter, One thing to consider is the value of your plane after it is
done. And also if you have a problem while flying cross country and
have to land some place unfamiliar. Airports across the country are
equipped with mechanics that look at Lycoming type engines all the time,
a subby maybe not. The subby has more possible failure modes that is
for sure. Only one spark plug per cylinder, for example. That engine
will not keep you climbing if it starts running on just 3. Consider
where you are flying most of the time and whether climbing is vital to
your safety. Reading the Eggenfeltner email is a good thing to do.
They are still discovering new things it seems every month (although I
have not read it lately). I went this same route three years ago and
even ordered a subby at one point. I like the features and ability of
the subby but decided that the proven Lycoming type was better for me.
In the end, I just decided I really did not want to be a test pilot for
Jan. Jan was very fair with me all the way. I like him. I have a
friend who is almost ready to start flying his RV6A with Eggenfeltner
subby. His installation looks more compact/complicated and totally
packed in there than a Lycoming type. Working on it going forward seems
like it will be a concern. You cannot get to anything without moving
something else out of the way it seems. However, It sounds great and
runs smoothly on the ground. Keep in mind It was not designed for
putting out 80 percent power at 3,500 rpm as it will be doing in the
air. Jan says no one has met the TBO yet. I wish he would run one to
that point and know the answer! (The longest running engine of his
still has only about 1,000 hours on it and at that point, it is not a
value yet). Although he thought so getting into it, I am not sure my
friend's total cost is any cheaper than something like a TMX-O360. If
you must have fuel injection in the Lycoming type, that is more of
course and you got that with the subby. With my TMX engine, I can burn
92 octane unleaded after 200 hours. It is good you are looking into
this early. Lots of stuff to consider and most folks have a slightly
different slant on priorities and risk.
I recommend you visit Jan's place of business if you can make a trip
out of it. I think a guy named Morris visited Jan about 3-4 years ago.
It might be in the RV7-List archives or the RV-List archives. His
posting influenced my decision. But all things change -- and as I said,
I like the features of the subby engine. AND -- I'd talk with Vans
before deciding on a 390. Best wishes.
Indiana Larry
----- Original Message -----
From: Peter Lythall <mailto:peter@nortech.bc.ca>
To: rv7-list@matronics.com
Sent: Wednesday, November 16, 2005 12:52 AM
Subject: RV7-List: Engine Choices
Hello,
Snip.......Now I need to decide on what powerplant in hang on
the front end of this thing and I am torn between a couple of choices. I
am looking for some input from other builders who have researched and/or
installed the Subaru H-6 engine.
At this juncture I am looking at either the io-360(tried and
true) or the Eggenfellner H-6(looks sharp and if packed with new type
technology, water cooled, lower op costs, lower tbo costs, and burns
mogas and 100ll). Another option is the new io-390 but I haven't really
looked at that. So any comments on the soob. I have discussed with
various folks including a local AME (great guy) and various pilots at
the hanger that I often show up for coffee at. I have watched the
eggenfellner yahoo list but I am still not entirely certain. So I am
looking for some totally biased input. If you have installed one of
these beasts or can direct me to some unhappy or happy owners that would
be fantastic.
Peter Lythall
Fort St. John, BC Canada
Message 5
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One thing you have a hard time pinning down is exactly what is the
cooling drag panalty of the water cooled motor. I know one guy who built
wo almost identical RV7's one with a 2.5l soob and the other with a
o360....the sooby cruised at 172 mph apparently. You can make it go
faster but you'll burn a lot more fuel doing so. Note the H6 motor is
around 220HP, if you crank it to overcome the cooling drag you'll burn
more fuel than an aircooled 360.
Note this is all from my desk research and a conglomeration of lots of
opinions. As one of my sooby friends said...Put yer Lycoming in your
plane and then we will compare lies...:)
Why is there more (alleged) drag?...Simple...The cyl heads on an
aircooled moter run much hotter than the radiators of an aircooled
motor...The heat regection is proportional to the temperature difference
between the thing you want cooled (head or rad) and the cooling air
multiplied by the air flow rate. So less temp difference means more
flowrate for the same power lost as heat...More flow means more drag.
Note that Vans has offered to do a back to back flyoff and this has not
happened yet. To me this was enough doubt to go with a Mattituck IO360
that I intend (after break in) to run on Mogas.
I don't know for sure but I doubt the sooby can be programmed to run
Lean of peak...In an IO360 this means 180mph at 7.5 GPH...Not bad!
Just in case your wondering if I'm an "airplane motor for airplanes"
dude....I already run a small subaru in my Zenair Zodiac...Its runs
great!
Frank
________________________________
From: owner-rv7-list-server@matronics.com
[mailto:owner-rv7-list-server@matronics.com] On Behalf Of Peter Lythall
Subject: RV7-List: Engine Choices
Hello,
I am working on my RV7 Empennage and have ordered my qb to pickup in mid
January. Now I want to minimize the shipping costs and I am going to
pickup the QB kit at Vans's. It will give me a nice break from work and
we can visit the inlaws on the way (what fun). Now I need to decide on
what powerplant in hang on the front end of this thing and I am torn
between a couple of choices. I am looking for some input from other
builders who have researched and/or installed the Subaru H-6 engine.
At this juncture I am looking at either the io-360(tried and true) or
the Eggenfellner H-6(looks sharp and if packed with new type technology,
water cooled, lower op costs, lower tbo costs, and burns mogas and
100ll). Another option is the new io-390 but I haven't really looked at
that. So any comments on the soob. I have discussed with various folks
including a local AME (great guy) and various pilots at the hanger that
I often show up for coffee at. I have watched the eggenfellner yahoo
list but I am still not entirely certain. So I am looking for some
totally biased input. If you have installed one of these beasts or can
direct me to some unhappy or happy owners that would be fantastic.
Peter Lythall
Fort St. John, BC Canada
Message 6
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--> RV7-List message posted by: "Rob Prior (rv7)" <rv7@b4.ca>
On 7:21:38 2005-11-16 "Hinde, Frank George (Corvallis)" <frank.hinde@hp.com> wrote:
> Why is there more (alleged) drag?...Simple...The cyl heads on an
> aircooled moter run much hotter than the radiators of an aircooled
> motor...The heat regection is proportional to the temperature
> difference between the thing you want cooled (head or rad) and the
> cooling air multiplied by the air flow rate. So less temp difference
> means more flowrate for the same power lost as heat...More flow means
> more drag.
Not saying it's possible with a Subaru installation (or that it's
impossible, either), but it is possible to realize additional *thrust* from
your water cooling system. There's at least one person here on the list
that flies a P-51 in his spare time (lucky bugger :), he would probably
know about that.
I remember an article in Sport Aviation a number of years ago about
maximizing performance that also mentioned this.
-Rob
Message 7
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--> RV7-List message posted by: "Hinde, Frank George (Corvallis)" <frank.hinde@hp.com>
Yes that is definatly a piece of fabled history and in theory it is
correct The idea being that as the rad heats the air going thru it, it
expands, thus acting like like a mini jet engine, turning some of the
waste heat power into thrust. Does this thrust exceed the extra
drag?..Maybe...However, in the real world to make that work requires the
rad to be in a duct under the plane.
Fact of the matter is, noone has successfully designed such a duct (and
associated "Thick radiator") in the world of homebuilt aviation.
Eggenfelner's (as are others) conversion is designed as a drop in for
the Lyc, using the same cowl.
My bet would be to realise what might in theory be a great design will
take a lot more investment than we have currently. Not saying someone
won't do it but it's not a "here today" product that is available.
What you will find is the sooby converters simply avoid talking about
it...That will work for a while and for those who don't care too much
about speed.
As someone said, the soob engine is turbine smooth, appaerently much
more pleasant to fly behind and compared with the other benefits of low
rebuild/parts cost makes it a clear winner.
For me, as Dan Checkoway said " performance is 99% of the deal", so a
lYC clone wins it.
Frank
-----Original Message-----
From: owner-rv7-list-server@matronics.com
[mailto:owner-rv7-list-server@matronics.com] On Behalf Of Rob Prior
(rv7)
Subject: RE: RV7-List: Engine Choices
--> RV7-List message posted by: "Rob Prior (rv7)" <rv7@b4.ca>
On 7:21:38 2005-11-16 "Hinde, Frank George (Corvallis)"
<frank.hinde@hp.com> wrote:
> Why is there more (alleged) drag?...Simple...The cyl heads on an
> aircooled moter run much hotter than the radiators of an aircooled
> motor...The heat regection is proportional to the temperature
> difference between the thing you want cooled (head or rad) and the
> cooling air multiplied by the air flow rate. So less temp difference
> means more flowrate for the same power lost as heat...More flow means
> more drag.
Not saying it's possible with a Subaru installation (or that it's
impossible, either), but it is possible to realize additional *thrust*
from your water cooling system. There's at least one person here on the
list that flies a P-51 in his spare time (lucky bugger :), he would
probably know about that.
I remember an article in Sport Aviation a number of years ago about
maximizing performance that also mentioned this.
-Rob
Message 8
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--> RV7-List message posted by: "Rob Prior (rv7)" <rv7@b4.ca>
On 9:34:02 2005-11-16 "Hinde, Frank George (Corvallis)" <frank.hinde@hp.com> wrote:
> Yes that is definatly a piece of fabled history and in theory it is
> correct The idea being that as the rad heats the air going thru it, it
> expands, thus acting like like a mini jet engine, turning some of the
> waste heat power into thrust. Does this thrust exceed the extra
> drag?..Maybe...However, in the real world to make that work requires
> the rad to be in a duct under the plane.
I'm not so sure the location is that relevant. I can't find the Sport
Aviation article right now, but I seem to recall it involved a conventional
looking aircraft, and a conventional cowling (but with highly specialized
inlets, exits, baffles, and plenum). Oh, and this was on an air-cooled
engine not a water-cooled one. But if they could get thrust out of an
air-cooled engine compartment (or at the very least offset a lot of the
cooling drag), then surely the same could be possible on a water cooled
install. Again, i'm not saying this *is* being done on the existing Subaru
installs. It probably isn't.
For more info, it's called the Meredith Effect, here's some light reading:
Air and Space Museum:
<http://www.airandspacemagazine.com/ASM/Mag/Supp/JJ99/Mustang.html>
<http://www.airandspacemagazine.com/ASM/Mag/Index/1996/AS/wmtm.html>
An archived post from rec.aviation.military:
<http://yarchive.net/mil/laminar_flow.html>
-Rob
Message 9
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| Subject: | Re: Engine Choices |
You mentioned 180mph on 7.5gph. On 7.5gph with my IO-360 I get just shy of 200mph
TAS (~170-175 KTAS).
Your mileage may vary. Literally.
Best part about my Lycoming? It doesn't have a computer with the AUTHORITY to
shut the engine down on my without my consent.
)_( Dan
RV-7 N714D (680 hours)
http://www.rvproject.com
----- Original Message -----
From: Hinde, Frank George (Corvallis)
To: rv7-list@matronics.com
Sent: Wednesday, November 16, 2005 7:21 AM
Subject: RE: RV7-List: Engine Choices
One thing you have a hard time pinning down is exactly what is the cooling drag
panalty of the water cooled motor. I know one guy who built wo almost identical
RV7's one with a 2.5l soob and the other with a o360....the sooby cruised
at 172 mph apparently. You can make it go faster but you'll burn a lot more fuel
doing so. Note the H6 motor is around 220HP, if you crank it to overcome the
cooling drag you'll burn more fuel than an aircooled 360.
Note this is all from my desk research and a conglomeration of lots of opinions.
As one of my sooby friends said...Put yer Lycoming in your plane and then
we will compare lies...:)
Why is there more (alleged) drag?...Simple...The cyl heads on an aircooled moter
run much hotter than the radiators of an aircooled motor...The heat regection
is proportional to the temperature difference between the thing you want cooled
(head or rad) and the cooling air multiplied by the air flow rate. So less
temp difference means more flowrate for the same power lost as heat...More
flow means more drag.
Note that Vans has offered to do a back to back flyoff and this has not happened
yet. To me this was enough doubt to go with a Mattituck IO360 that I intend
(after break in) to run on Mogas.
I don't know for sure but I doubt the sooby can be programmed to run Lean of
peak...In an IO360 this means 180mph at 7.5 GPH...Not bad!
Just in case your wondering if I'm an "airplane motor for airplanes" dude....I
already run a small subaru in my Zenair Zodiac...Its runs great!
Frank
From: owner-rv7-list-server@matronics.com [mailto:owner-rv7-list-server@matronics.com] On Behalf Of Peter Lythall
Sent: Tuesday, November 15, 2005 10:53 PM
To: rv7-list@matronics.com
Subject: RV7-List: Engine Choices
Hello,
I am working on my RV7 Empennage and have ordered my qb to pickup in mid January.
Now I want to minimize the shipping costs and I am going to pickup the QB
kit at Vans's. It will give me a nice break from work and we can visit the inlaws
on the way (what fun). Now I need to decide on what powerplant in hang on
the front end of this thing and I am torn between a couple of choices. I am
looking for some input from other builders who have researched and/or installed
the Subaru H-6 engine.
At this juncture I am looking at either the io-360(tried and true) or the Eggenfellner
H-6(looks sharp and if packed with new type technology, water cooled,
lower op costs, lower tbo costs, and burns mogas and 100ll). Another option
is the new io-390 but I haven't really looked at that. So any comments on the
soob. I have discussed with various folks including a local AME (great guy) and
various pilots at the hanger that I often show up for coffee at. I have watched
the eggenfellner yahoo list but I am still not entirely certain. So I am looking
for some totally biased input. If you have installed one of these beasts
or can direct me to some unhappy or happy owners that would be fantastic.
Peter Lythall
Fort St. John, BC Canada
Message 10
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Not bad just got even better...:)
Frank
Do not archive
________________________________
From: owner-rv7-list-server@matronics.com
[mailto:owner-rv7-list-server@matronics.com] On Behalf Of Dan Checkoway
Subject: Re: RV7-List: Engine Choices
You mentioned 180mph on 7.5gph. On 7.5gph with my IO-360 I get just shy
of 200mph TAS (~170-175 KTAS).
Your mileage may vary. Literally.
Best part about my Lycoming? It doesn't have a computer with the
AUTHORITY to shut the engine down on my without my consent.
)_( Dan
RV-7 N714D (680 hours)
http://www.rvproject.com
----- Original Message -----
From: Hinde, Frank George (Corvallis)
<mailto:frank.hinde@hp.com>
To: rv7-list@matronics.com
Sent: Wednesday, November 16, 2005 7:21 AM
Subject: RE: RV7-List: Engine Choices
One thing you have a hard time pinning down is exactly what is
the cooling drag panalty of the water cooled motor. I know one guy who
built wo almost identical RV7's one with a 2.5l soob and the other with
a o360....the sooby cruised at 172 mph apparently. You can make it go
faster but you'll burn a lot more fuel doing so. Note the H6 motor is
around 220HP, if you crank it to overcome the cooling drag you'll burn
more fuel than an aircooled 360.
Note this is all from my desk research and a conglomeration of
lots of opinions. As one of my sooby friends said...Put yer Lycoming in
your plane and then we will compare lies...:)
Why is there more (alleged) drag?...Simple...The cyl heads on an
aircooled moter run much hotter than the radiators of an aircooled
motor...The heat regection is proportional to the temperature difference
between the thing you want cooled (head or rad) and the cooling air
multiplied by the air flow rate. So less temp difference means more
flowrate for the same power lost as heat...More flow means more drag.
Note that Vans has offered to do a back to back flyoff and this
has not happened yet. To me this was enough doubt to go with a Mattituck
IO360 that I intend (after break in) to run on Mogas.
I don't know for sure but I doubt the sooby can be programmed to
run Lean of peak...In an IO360 this means 180mph at 7.5 GPH...Not bad!
Just in case your wondering if I'm an "airplane motor for
airplanes" dude....I already run a small subaru in my Zenair
Zodiac...Its runs great!
Frank
________________________________
From: owner-rv7-list-server@matronics.com
[mailto:owner-rv7-list-server@matronics.com] On Behalf Of Peter Lythall
Sent: Tuesday, November 15, 2005 10:53 PM
To: rv7-list@matronics.com
Subject: RV7-List: Engine Choices
=09
=09
Hello,
I am working on my RV7 Empennage and have ordered my qb to
pickup in mid January. Now I want to minimize the shipping costs and I
am going to pickup the QB kit at Vans's. It will give me a nice break
from work and we can visit the inlaws on the way (what fun). Now I need
to decide on what powerplant in hang on the front end of this thing and
I am torn between a couple of choices. I am looking for some input from
other builders who have researched and/or installed the Subaru H-6
engine.
At this juncture I am looking at either the io-360(tried and
true) or the Eggenfellner H-6(looks sharp and if packed with new type
technology, water cooled, lower op costs, lower tbo costs, and burns
mogas and 100ll). Another option is the new io-390 but I haven't really
looked at that. So any comments on the soob. I have discussed with
various folks including a local AME (great guy) and various pilots at
the hanger that I often show up for coffee at. I have watched the
eggenfellner yahoo list but I am still not entirely certain. So I am
looking for some totally biased input. If you have installed one of
these beasts or can direct me to some unhappy or happy owners that would
be fantastic.
Peter Lythall
Fort St. John, BC Canada
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| Subject: | Re: Engine Choices |
--> RV7-List message posted by: Tyler Bryant <tylerii@infoave.net>
Read the current issue of the
rvator
There is a good article on engine selection
Tyler N442TJ
Peter Lythall wrote:
> Hello,
>
> I am working on my RV7 Empennage and have ordered my qb to pickup in
> mid January. Now I want to minimize the shipping costs and I am going
> to pickup the QB kit at Vanss. It will give me a nice break from work
> and we can visit the inlaws on the way (what fun). Now I need to
> decide on what powerplant in hang on the front end of this thing and I
> am torn between a couple of choices. I am looking for some input from
> other builders who have researched and/or installed the Subaru H-6
> engine.
>
> At this juncture I am looking at either the io-360(tried and true) or
> the Eggenfellner H-6(looks sharp and if packed with new type
> technology, water cooled, lower op costs, lower tbo costs, and burns
> mogas and 100ll). Another option is the new io-390 but I havent
> really looked at that. So any comments on the soob. I have discussed
> with various folks including a local AME (great guy) and various
> pilots at the hanger that I often show up for coffee at. I have
> watched the eggenfellner yahoo list but I am still not entirely
> certain. So I am looking for some totally biased input. If you have
> installed one of these beasts or can direct me to some unhappy or
> happy owners that would be fantastic.
>
> Peter Lythall
>
> Fort St. John, BC Canada
>
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