Author: Paul Pocock <ppocock@...> Time: Mon Aug 6, 2001 4:40 am PDT Link
Wow, a lighter weight, fuel easy, self cooled, simple to operate, injected
constant speed. What's the catch? 3800 rpm, does it use a shorter
prop? What would be the TBO?
Paul Pocock
At 04:34 AM 8/6/01 +0000, you wrote:
>
> > NOW, IF YOU ARE ONLY INTERESTED IN MAXIMUM CLIMB AND MAX CRUISING
>SPEED, THEN
> > THE 200 HP ENGINE IS FOR YOU.
> >
> > Continued tomorrow
> >
> > Jan Eggenfellner
>
>I think you meant "NOW, IF YOU ARE ONLY INTERESTED IN MAXIMUM CLIMB
>AND MAX CRUISING SPEED, THEN
>THE turbo or supercharged Subaru ENGINE IS FOR YOU".
>Robert Paisley
>Van's Air Force - World Wide Wing
>www.vansaircraft.net
>Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
Author: eaainc@... Time: Mon Aug 6, 2001 5:01 am PDT Link
In a message dated 8/6/01 7:41:26 AM Eastern Daylight Time,
ppocock@m... writes:
Wow, a lighter weight, fuel easy, self cooled, simple to operate, injected
constant speed. What's the catch? 3800 rpm, does it use a shorter
prop? What would be the TBO?
Paul Pocock
(end of quote)
THERE IS NO CATCH, JUST HAVE TO BE WILLING TO STEP INTO THE NEXT CENTURY:)
THE ENGINE SPEED IS REDUCED THROUGH A GEAR DRIVE BY A FACTOR OF 1.82 / 1 SO
THE 3800 ECONOMY CRUISE ENGINE RPM WOULD BE 2100 PROP RPM. TBO IS 2000+ HR.
JAN EGGENFELLNER
Author: eaainc@... Time: Thu Aug 16, 2001 7:41 pm PDT Link
Updates on the supercharger installation tomorrow :)
Jan Eggenfellner
Author: "Gregory Young" <gyoung@...> Time: Thu Aug 16, 2001 9:31 pm PDT Link
Robert,
Scott is correct. Engines are rated at sea level, standard atmospheric conditions. The IO-360 angle valve is rated by Lycoming at 200 hp, the IO-360-B parallel valve and most other O-360 models are rated at 180 hp. Full throttle does not necessarily mean 100%, it means "wide-open" throttle which will allow the engine to develop 100% at sea level and roughly 75% at 8000 ft. The uninstalled power curves are not linear and are then further complicated by installation effects.
Greg Young
Scott,
Don't all the airplane manuals state full throttle = 75% power? isn't
that 75% power at sea level?
I'm not arguing with you. I just want to get a concensus on what 75%
power means before going to the next statements.
Are there any engine builders listening who have dynoed these motors
at 2700rpm and have corrected (to sea level)HP numbers.
In any case, at 8000 ft you have lost 27% of your sea level power. If
full throttle on the IO-360 is 150HP at sea level. Then the IO-360 is
109HP at 8000 ft.
The (normally aspirated) Subaru will go through the same power
derating of course. (come on turbocharger!).
I know that doesn't answer the earlier question. I am anxious to post
the real answer to the climb rate question in about a year.
Robert Paisley
---In RV7and7A@y..., "Scott Morton" <mortonsf@f...> wrote:
> The IO-360 will run at 75% with full throttle around 8000 feet
producing
> about 150 HP - in an RV 7, that should be about 207 mph.
>
>I assume that the recommended max cruise setting for the Subaru
will be 75%.
> I calculate that the Subaru at 75% power will be 124 HP - any idea
what that
> will do to cruise?? 180 mph?
> -----Original Message-----
> From: eaainc@a... [mailto:eaainc@a...]
> Sent: Sunday, August05, 2001 9:35 PM
> To: RV7and7A@y...
> Subject: Re: [RV7and7A] Re:ANSWER TO ENGINE QUESTION 1
> In a message dated 8/5/01 2:52:36 PM Eastern Daylight Time,
> bandit1702@y... writes:
> Can you please tell us when we can expect the real world climb
and
> cruise performance figures flying RV-XX with your Eggenfellner
> (non-supercharged) Subaru engine?
(end of quote)
Author: robert@... Time: Thu Aug 16, 2001 10:21 pm PDT Link
Gregory,
Your statement is what I was getting at. Full throttle is not full
rated horsepower, it's 75% power. You can't rev the Lycs high enough
to get to the top of the horsepower curve. I.e. full throttle at sea
level = 75% horsepower.
That's one nice thing about the auto engine conversions - you can rev
the motor through it's power band.
This is one reason it's hard to get apples to apples comparisons on
Lyc vs. auto conversion from a paper analysis speculation standpoint.
So I am still questioning the 200hp at sea level, 150hp at 8000 ft
conclusion. If you know for a fact the "200 horse" motor makes that HP
at 2700 rpm at sea level please correct me and I'll shut up. If not
we can look for more data to get the true scoop.
Robert Paisley
(Subaru powered wannabe)
--- In RV7and7A@y..., "Gregory Young" <gyoung@c...> wrote:
> Robert,
> Scott is correct. Engines are rated at sea level, standard
atmospheric
> conditions. The IO-360 angle valve is rated by Lycoming at 200 hp,
the
> IO-360-B parallel valve and most other O-360 models are rated at
180 hp.
> Full throttle does not necessarily mean 100%, it means "wide-open"
throttle
> which will allow the engine to develop 100% at sea level and
roughly 75% at
> 8000 ft. The uninstalled power curves are not linear and are then
further
> complicated by installation effects.
> Greg Young
>
> Scott,
> Don't all the airplane manuals state full throttle = 75% power?
isn't
> that 75% power at sea level?
> I'm not arguing with you. I just want to get a concensus on what
75%
> power means before going to the next statements.
> Are there any engine builders listening who have dynoed these
motors
> at 2700rpm and have corrected (to sea level)HP numbers.
>
> In any case, at 8000 ft you have lost 27% of your sea level
power. If
> full throttle on the IO-360 is 150HP at sea level. Then the IO-
360 is
> 109HP at 8000 ft.
>
> The (normally aspirated) Subaru will go through the same power
> derating of course. (come on turbocharger!).
>
> I know that doesn't answer the earlier question. I am anxious to
post
> the real answer to the climb rate question in about a year.
> Robert Paisley
> --- In RV7and7A@y..., "Scott Morton" <mortonsf@f...> wrote:
> > The IO-360 will run at 75% with full throttle around 8000 feet
> producing
> > about 150 HP - in an RV 7, that should be about 207 mph.
> >
> > I assume that the recommended max cruise setting for the Subaru
> will be 75%.
> > I calculate that the Subaru at 75% power will be 124 HP - any
idea
> what that
> > will do to cruise?? 180 mph?
> > -----Original Message-----
> > From: eaainc@a... [mailto:eaainc@a...]
> > Sent: Sunday, August 05, 2001 9:35 PM
> > To: RV7and7A@y...
> > Subject: Re: [RV7and7A] Re:ANSWER TO ENGINE QUESTION 1
> > In a message dated 8/5/01 2:52:36 PM Eastern Daylight Time,
> > bandit1702@y... writes:
> > Can you please tell us when we can expect the real world
climb
> and
> > cruise performance figures flying RV-XX with your
Eggenfellner
> > (non-supercharged) Subaru engine?
Author: robert@... Time: Tue Aug 21, 2001 10:18 am PDT Link
OK Greg,
I waded through the Lycoming HP chart you posted (thank you).
The Lycoming data shows:
200HP at sea level
150HP at 8000 ft
130HP at 12000 ft
Using similar derating for altitude, the Subaru numbers should be:
165HP at sea level
124HP at 8000 ft
107HP at 12000 ft
(or 82% of the Lyc power)
(35% of the sea level power is lost by both engines at 12,000 ft)
So, in a performance aircraft such as the RV7, the best (alternative)
engine solution would seem to be a turbo or supercharged Subaru (if
you are into HP, climb rates and max cruise speed).
Turbo Subaru performance:
200HP at sea level
200HP at 8000 ft (33% increase over Lyc)
200HP at 12000 ft (54% increase over Lyc)
Robert Paisley
--- In RV7and7A@y..., "Gregory Young" <gyoung@c...> wrote:
> Robert,
>
> Yes, we know for a fact that a 200hp rated Lyc IO-360 will produce
200hp at
> 2700 rpm at sea level. To illustrate it I've attached a power chart
from the
> Lycoming xx-360 Operators Manual. If you haven't seen one of these
before,
> check the POH for whatever aircraft you're renting/flying - they'll
be
> something similar for that particular engine. There are plenty of
arguments
> to sort through on both sides of the Lycoming vs auto engine
choice. Just
> don't do it because you don't think a 200 hp aircraft engine will
actually
> produce 200 hp - it will and the certification process goes to
great lengths
> to prove it will do so reliably. Choose carefully.
>
> Greg Young
Author: "Jim Carter" <jim@...> Time: Tue Aug 21, 2001 11:03 am PDT Link
Hi Robert,
<![if !supportEmptyParas]> <![endif]>
I have been following the gist of the discussion on HP for the past several days. My only comment is that according toa message I received from Jan, his supercharged Subaru will be 165 HP at sea level and 165 HP at altitude. More a case of “super normalizing” rather than supercharging. Course this is always subject to change, keeping in mind that the trade-off is less reliability with greater boost.
<![if !supportEmptyParas]> <![endif]>
Jim Carter
<![if !supportEmptyParas]> <![endif]>
<![if !supportEmptyParas]> <![endif]>
-----Original Message-----
From: robert@protekperformance.com [mailto:robert@p...]
Sent: Tuesday, 2001.08.21 10:12 AM
To: RV7and7A@yahoogroups.com
Subject: [RV7and7A] Re:ANSWER TO ENGINE QUESTION 1
<![if !supportEmptyParas]> <![endif]>
OK Greg,
I waded through the Lycoming HP chart you posted (thank you).
The Lycoming data shows:
200HP at sea level
150HP at 8000 ft
130HP at 12000 ft
Using similar derating for altitude, the Subaru numbers should be:
165HP at sea level
124HP at 8000 ft
107HP at 12000 ft
(or 82% of the Lyc power)
(35% of the sea level power is lost by both engines at 12,000 ft)
So, in a performance aircraft such as the RV7, the best (alternative)
engine solution would seem to be a turbo or supercharged Subaru (if
you are into HP, climb rates and max cruise speed).
Turbo Subaru performance:
200HP at sea level
200HP at 8000 ft (33% increase over Lyc)
200HP at 12000 ft (54% increase over Lyc)
Robert Paisley
<![if !supportLineBreakNewLine]> <![endif]>
Van's Air Force - World Wide Wing
www.vansaircraft.net
Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service (http://docs.yahoo.com/info/terms/).
Author: "Peter W Mountain" <peterm@...> Time: Tue Aug 21, 2001 1:17 pm PDT Link
This is what you said in your first reply. Maybe Greg did not read the
posting fully.
I myself began an argument with Rob on Lycoming vs Subaru 3 months ago when
this group was just beginning :)
My Subaru has been on order for 2 months now.
Regards
Peter.
> -----Original Message-----
> From: robert@p... [mailto:robert@p...]
> Sent: Tuesday, August 21, 2001 10:12 AM
> To: RV7and7A@yahoogroups.com
> Subject: [RV7and7A] Re:ANSWER TO ENGINE QUESTION 1
> OK Greg,
> I waded through the Lycoming HP chart you posted (thank you).
> The Lycoming data shows:
> 200HP at sea level
> 150HP at 8000 ft
> 130HP at 12000 ft
>
> Using similar derating for altitude, the Subaru numbers should be:
> 165HP at sea level
> 124HP at 8000 ft
> 107HP at 12000 ft
> (or 82% of the Lyc power)
> (35% of the sea level power is lost by both engines at 12,000 ft)
>
> So, in a performance aircraft such as the RV7, the best (alternative)
> engine solution would seem to be a turbo or supercharged Subaru (if
> you are into HP, climb rates and max cruise speed).
> Turbo Subaru performance:
> 200HP at sea level
> 200HP at 8000 ft (33% increase over Lyc)
> 200HP at 12000 ft (54% increase over Lyc)
> Robert Paisley
> --- In RV7and7A@y..., "Gregory Young" <gyoung@c...> wrote:
> > Robert,
> >
> > Yes, we know for a fact that a 200hp rated Lyc IO-360 will produce
> 200hp at
> > 2700 rpm at sea level. To illustrate it I've attached a power chart
> from the
> > Lycoming xx-360 Operators Manual. If you haven't seen one of these
> before,
> > check the POH for whatever aircraft you're renting/flying - they'll
> be
> > something similar for that particular engine. There are plenty of
> arguments
> > to sort through on both sides of the Lycoming vs auto engine
> choice. Just
> > don't do it because you don't think a 200 hp aircraft engine will
> actually
> > produce 200 hp - it will and the certification process goes to
> great lengths
> > to prove it will do so reliably. Choose carefully.
> >
> > Greg Young
> Van's Air Force - World Wide Wing
> www.vansaircraft.net
> Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
Author: eaainc@... Time: Tue Aug 21, 2001 1:40 pm PDT Link
In a message dated 8/21/01 2:05:04 PM Eastern Daylight Time, jim@t...
writes:
A message I received from Jan, his supercharged Subaru will be 165 HP at sea
level and 165 HP at altitude. More a case of “super normalizing” rather
than supercharging. Course this is always subject to change, keeping in
mind that the tradeoff is less reliability with greater boost.
(end of quote)
This is where we will start and I feel it is where we will end up. But
remember, 90% of your flight is at altitude, going somewhere, so we have the
power where it counts with a much lighter engine down low for good climb.
Jan Eggenfellner
Author: "Scott Morton" <mortonsf@...> Time: Thu Aug 23, 2001 8:47 am PDT Link
Even though the Turbo Subaru will be able to achieve 165 Hp at 8,000 feet - that doesn't mean you can run it there in cruise. My understanding from Jan is that it still has all the normal 75% of full power restrictions. So at 8,000 feet the Lycoming can achieve only 150 Hp, but that is 75% power. The Turbo Subaru will be 124 Hp at 75% at 8,000 (and probably still be ableto do 124 at 12,000 where the Lycoming will only achieve 107 Hp.)
Quote:
-----Original Message-----
From: eaainc@a... [mailto:eaainc@a...]
Sent: Tuesday, August 21, 2001 4:38 PM
To: RV7and7A@yahoogroups.com
Subject: Re: [RV7and7A] Re:ANSWER TO ENGINE QUESTION 1
In a message dated 8/21/01 2:05:04 PM Eastern Daylight Time, jim@t...
writes:
A message I received from Jan, his supercharged Subaru willbe 165 HP at sea
level and 165 HP at altitude. More a case of “super normalizing” rather
than supercharging. Course this is always subject to change, keeping in
mind that the tradeoff is less reliability with greater boost.
(end of quote)
This is where we will start and I feel it is where we will end up. But
remember, 90% of your flight is at altitude, going somewhere, so we have the
power where it counts with a much lighter engine down low for good climb.
Jan Eggenfellner
Van's Air Force - World Wide Wing
www.vansaircraft.net
Your use of Yahoo! Groups is subject to the Yahoo! Termsof Service (http://docs.yahoo.com/info/terms/).
(end of quote)
Author: eaainc@... Time: Thu Aug 23, 2001 4:27 pm PDT Link
In a message dated 8/23/01 11:51:19 AM Eastern Daylight Time,
mortonsf@f... writes:
Even though the Turbo Subaru will be able to achieve 165 HP at 8,000 feet --
that doesn't mean you can run it there in cruise. My understanding from
Jan is that it still has all the normal 75% of full power restrictions. So
at 8,000 feet the Lycoming can achieve only 150 HP, but that is 75% power.
The Turbo Subaru will be 124 HP at 75% at 8,000 (and probably still be able
to do 124 at 12,000 where the Lycoming will only achieve 107 HP.)
(end of quote)
It is realistic to think that the Supercharged Subaru will produce 140 HP at
8000 feet, due to an efficient induction system, if we run 1 LB of pressure.
The Subaru is lighter than the IO-360 and would do good.
Like I have said before, for those that cannot appreciate the multitude of
advantages of the Subaru engine over the air-cooled engine, and where the
only thing that matters is the maximum HP, then I would go with the IO-360.
For a review of these advantages, go to www.subaruaircraft.com (http://www.subaruaircraft.com/) :)
Jan Eggenfellner