Today's Message Index:
----------------------
1. 07:29 AM - Results of GAMI Lean Tests (Lynn Matteson)
2. 08:12 AM - Re: Results of GAMI Lean Tests (BobsV35B@aol.com)
3. 01:01 PM - Re: Results of GAMI Lean Tests (Lynn Matteson)
4. 01:26 PM - Re: Results of GAMI Lean Tests (BobsV35B@aol.com)
5. 02:38 PM - Re: Results of GAMI Lean Tests (Lynn Matteson)
6. 06:53 PM - Jab 3300 vs Rotax 912ULS performance - technical interpretation (Victor Menkal)
7. 07:20 PM - Re: Oil (ces308)
8. 10:48 PM - Re: Results of GAMI Lean Tests (Terry Phillips)
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| Subject: | Results of GAMI Lean Tests |
I flew the GAMI Lean Test(s) today, and found the following: All
temps are in degrees F.
Three different tests, flown at 4500', 6000-6300', and
6500-7200'....these were supposed to be at a fixed altitude, but you
know how that goes, when you're busy writing things down, and nobody
else to keep track of the airplane.
Cutting right to the numbers, I showed a .1 gph spread on one test,
and two tests of .3 gph spread. Looking at the results, the rear
cylinders usually peaked first, and were in the 1387- 1430 range when
they did.
The front two cylinders usually peaked last, and were in the
1333-1352 range when they did peak. In one test, at 2750 rpm
(6000-6300'), #'s 1 and 3 peaked first at 2.8 gph, and 2 and 4
followed at 2.7 gph. Rpm had dropped down to 2700 during this test.
CHT's not recorded during the 1&3 peaks, but they were (1) 298, (2)
306, (3) 305, (4) 316.
At 2800 rpm (6500, wandering up to 7200'), #'s 3 and 4 peaked at 1430
and 1410 resp., at 3.2 gph, and 1 and 2 at 1333 and 1352 resp., at
2.9 gph. Rpm went up to 2830. CHT's were (same order, 1,2,3,4)=
321,323, 311,and 322 when the last 2 cylinders peaked
At 2860 rpm (4500'), #3 peaked at 1431 F. at 3.1 gph, #4 at 1402 at
2.9, and #'s 1 and 2 at 1351 and 1337 respectively at 2.8 gph. Rpm
stayed the same, as near as I could tell. This ws the first test, and
I wasn't quit up to the task as yet. Once I got going, the recording
was a little better, but still not great.
These findings pretty much parallel the findings that I recorded with
the Bing carb, in that just a little rpm change can swap the hot EGT
from one side to another, or even on the same side. I've even seen
the higher numbers pass each other on the way up and down. Sometimes
I've seen #2 (left front) get up to the 1400's, but it doesn't seem
to last long. This tells me that both the Bing and the Rotec TBI
suffer from manifolding problems, or maybe just plain lack of
turbulence or even distribution of the fuel.
Overall, I don't think these numbers are too bad, and the spread of .
1 to .3 is better than the GAMI target of .5, but this is a smaller
engine, and the fuel doesn't have to go as far. That might be a naive
way to look at it, but it seems to make sense (so it's probably
wrong). : )
There ya go, engineers, have at it, and tell me what I missed. I plan
on running another test or more, so if anybody sees something I
should do different, holler.
Lynn Matteson
Kitfox IV Speedster, taildragger
Jabiru 2200, #2062, 739.7 hrs
Sensenich 62"x46" Wood prop
Electroair direct-fire ignition system
Rotec TBI-40 injection
Status: flying
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| Subject: | Re: Results of GAMI Lean Tests |
Good Morning Lynn,
Thanks for the data. I agree that the .1 split seems great.(As in very
good) At your fuel flows, I think a split of .3 needs to be looked at, but for
an engine that does not have direct cylinder fuel injection, your numbers
are pretty good. Small changes in airflow velocity could certainly make the
distribution change. All in all, I would say things are going well!
Thanks again for letting us know what is happening.
Keep in mind that the actual temperatures attained are immaterial. It is
the split between when they go lean that is important.
That is why Al Hundere always refused to have the actual temperature
displayed on his ALCOR instruments.
Happy Skies,
Old Bob
In a message dated 8/19/2009 9:29:45 A.M. Central Daylight Time,
lynnmatt@jps.net writes:
--> JabiruEngine-List message posted by: Lynn Matteson <lynnmatt@jps.net>
I flew the GAMI Lean Test(s) today, and found the following: All
temps are in degrees F.
Three different tests, flown at 4500', 6000-6300', and
6500-7200'....these were supposed to be at a fixed altitude, but you
know how that goes, when you're busy writing things down, and nobody
else to keep track of the airplane.
Cutting right to the numbers, I showed a .1 gph spread on one test,
and two tests of .3 gph spread. Looking at the results, the rear
cylinders usually peaked first, and were in the 1387- 1430 range when
they did.
The front two cylinders usually peaked last, and were in the
1333-1352 range when they did peak. In one test, at 2750 rpm
(6000-6300'), #'s 1 and 3 peaked first at 2.8 gph, and 2 and 4
followed at 2.7 gph. Rpm had dropped down to 2700 during this test.
CHT's not recorded during the 1&3 peaks, but they were (1) 298, (2)
306, (3) 305, (4) 316.
At 2800 rpm (6500, wandering up to 7200'), #'s 3 and 4 peaked at 1430
and 1410 resp., at 3.2 gph, and 1 and 2 at 1333 and 1352 resp., at
2.9 gph. Rpm went up to 2830. CHT's were (same order, 1,2,3,4)=
321,323, 311,and 322 when the last 2 cylinders peaked
At 2860 rpm (4500'), #3 peaked at 1431 F. at 3.1 gph, #4 at 1402 at
2.9, and #'s 1 and 2 at 1351 and 1337 respectively at 2.8 gph. Rpm
stayed the same, as near as I could tell. This ws the first test, and
I wasn't quit up to the task as yet. Once I got going, the recording
was a little better, but still not great.
These findings pretty much parallel the findings that I recorded with
the Bing carb, in that just a little rpm change can swap the hot EGT
from one side to another, or even on the same side. I've even seen
the higher numbers pass each other on the way up and down. Sometimes
I've seen #2 (left front) get up to the 1400's, but it doesn't seem
to last long. This tells me that both the Bing and the Rotec TBI
suffer from manifolding problems, or maybe just plain lack of
turbulence or even distribution of the fuel.
Overall, I don't think these numbers are too bad, and the spread of .
1 to .3 is better than the GAMI target of .5, but this is a smaller
engine, and the fuel doesn't have to go as far. That might be a naive
way to look at it, but it seems to make sense (so it's probably
wrong). : )
There ya go, engineers, have at it, and tell me what I missed. I plan
on running another test or more, so if anybody sees something I
should do different, holler.
Lynn Matteson
Kitfox IV Speedster, taildragger
Jabiru 2200, #2062, 739.7 hrs
Sensenich 62"x46" Wood prop
Electroair direct-fire ignition system
Rotec TBI-40 injection
Status: flying
Message 3
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| Subject: | Re: Results of GAMI Lean Tests |
Got any ideas, Bob, on how to change the airflow velocity? I'm all
ears. I'm envisioning a hacksaw cut into an intake tube and welding
in a steel plate of some size to slow down some of the flow, and
divert it to other tubes, but that's the shade-tree guy coming out of
me.
Realistically, though, maybe a more centralized carb, with equal-
length runners would help, but the oil pan is right in the
way....hmmmm, dry sump? Now we're going the way of Rotax, and that's
not good.
Of course, individual squirters into each intake tube, right at the
head would help, and I happen to know of a place out west that is
good at making these things. : ) The funny part of that idea is
that's the direction I was thinking of going when I learned about the
Rotec TBI.
I sure wish I had a junk Jabiru engine I could play around with, to
help visualize some ideas, and not have to spend so much time with my
cowl off, "imagineering" things.
Lynn Matteson
Kitfox IV Speedster, taildragger
Jabiru 2200, #2062, 739.7 hrs
Sensenich 62"x46" Wood prop
Electroair direct-fire ignition system
Rotec TBI-40 injection
Status: flying
On Aug 19, 2009, at 10:59 AM, BobsV35B@aol.com wrote:
> Good Morning Lynn,
>
> Thanks for the data. I agree that the .1 split seems great.(As in
> very good) At your fuel flows, I think a split of .3 needs to be
> looked at, but for an engine that does not have direct cylinder
> fuel injection, your numbers are pretty good. Small changes in
> airflow velocity could certainly make the distribution change. All
> in all, I would say things are going well!
>
> Thanks again for letting us know what is happening.
>
> Keep in mind that the actual temperatures attained are immaterial.
> It is the split between when they go lean that is important.
>
> That is why Al Hundere always refused to have the actual
> temperature displayed on his ALCOR instruments.
>
> Happy Skies,
>
> Old Bob
>
> In a message dated 8/19/2009 9:29:45 A.M. Central Daylight Time,
> lynnmatt@jps.net writes:
> <lynnmatt@jps.net>
>
> I flew the GAMI Lean Test(s) today, and found the following: All
> temps are in degrees F.
>
> Three different tests, flown at 4500', 6000-6300', and
> 6500-7200'....these were supposed to be at a fixed altitude, but you
> know how that goes, when you're busy writing things down, and nobody
> else to keep track of the airplane.
>
> Cutting right to the numbers, I showed a .1 gph spread on one test,
> and two tests of .3 gph spread. Looking at the results, the rear
> cylinders usually peaked first, and were in the 1387- 1430 range when
> they did.
>
> The front two cylinders usually peaked last, and were in the
> 1333-1352 range when they did peak. In one test, at 2750 rpm
> (6000-6300'), #'s 1 and 3 peaked first at 2.8 gph, and 2 and 4
> followed at 2.7 gph. Rpm had dropped down to 2700 during this test.
> CHT's not recorded during the 1&3 peaks, but they were (1) 298, (2)
> 306, (3) 305, (4) 316.
>
> At 2800 rpm (6500, wandering up to 7200'), #'s 3 and 4 peaked at 1430
> and 1410 resp., at 3.2 gph, and 1 and 2 at 1333 and 1352 resp., at
> 2.9 gph. Rpm went up to 2830. CHT's were (same order, 1,2,3,4)
> 321,323, 311,and 322 when the last 2 cylinders peaked
>
> At 2860 rpm (4500'), #3 peaked at 1431 F. at 3.1 gph, #4 at 1402 at
> 2.9, and #'s 1 and 2 at 1351 and 1337 respectively at 2.8 gph. Rpm
> stayed the same, as near as I could tell. This ws the first test, and
> I wasn't quit up to the task as yet. Once I got going, the recording
> was a little better, but still not great.
>
> These findings pretty much parallel the findings that I recorded with
> the Bing carb, in that just a little rpm change can swap the hot EGT
> from one side to another, or even on the same side. I've even seen
> the higher numbers pass each other on the way up and down. Sometimes
> I've seen #2 (left front) get up to the 1400's, but it doesn't seem
> to last long. This tells me that both the Bing and the Rotec TBI
> suffer from manifolding problems, or maybe just plain lack of
> turbulence or even distribution of the fuel.
>
> Overall, I don't think these numbers are too bad, and the spread of .
> 1 to .3 is better than the GAMI target of .5, but this is a smaller
> engine, and the fuel doesn't have to go as far. That might be a naive
> way to look at it, but it seems to make sense (so it's probably
> wrong). : )
>
> There ya go, engineers, have at it, and tell me what I missed. I plan
> on running another test or more, so if anybody sees something I
> should do different, holler.
>
>
> Lynn Matteson
> Kitfox IV Speedster, taildragger
> Jabiru 2200, #2062, 739.7 hrs
> Sensenich 62"x46" Wood prop
> Electroair direct-fire ignition system
> Rotec TBI-40 injection
> Status: ==============================================
> ================================================ -
> MATRONICS WEB FORUMS
> ================================================ - List
> Contribution Web Site sp;
> ==================================================
>
>
> www.matronics.com/contribution _-
> ===========================================================
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| Subject: | Re: Results of GAMI Lean Tests |
Good Afternoon Lynn,
Sounds to me like you are way ahead of anything I might suggest.
It is a two pronged problem. The first thing is to get equal air to each
cylinder and the second thing is to get equal fuel to each cylinder.
Messing with the flow has the potential of upsetting the balance or making
it better. I guess that is why we call it experimental!
Keep that information coming!
Remember that the mortal enemy of good enough is the search for perfection.
Happy Skies,
Old Bob
In a message dated 8/19/2009 3:01:47 P.M. Central Daylight Time,
lynnmatt@jps.net writes:
--> JabiruEngine-List message posted by: Lynn Matteson <lynnmatt@jps.net>
Got any ideas, Bob, on how to change the airflow velocity? I'm all
ears. I'm envisioning a hacksaw cut into an intake tube and welding
in a steel plate of some size to slow down some of the flow, and
divert it to other tubes, but that's the shade-tree guy coming out of
me.
Realistically, though, maybe a more centralized carb, with equal-
length runners would help, but the oil pan is right in the
way....hmmmm, dry sump? Now we're going the way of Rotax, and that's
not good.
Of course, individual squirters into each intake tube, right at the
head would help, and I happen to know of a place out west that is
good at making these things. : ) The funny part of that idea is
that's the direction I was thinking of going when I learned about the
Rotec TBI.
I sure wish I had a junk Jabiru engine I could play around with, to
help visualize some ideas, and not have to spend so much time with my
cowl off, "imagineering" things.
Lynn Matteson
Kitfox IV Speedster, taildragger
Jabiru 2200, #2062, 739.7 hrs
Sensenich 62"x46" Wood prop
Electroair direct-fire ignition system
Rotec TBI-40 injection
Status: flying
On Aug 19, 2009, at 10:59 AM, BobsV35B@aol.com wrote:
> Good Morning Lynn,
>
> Thanks for the data. I agree that the .1 split seems great.(As in
> very good) At your fuel flows, I think a split of .3 needs to be
> looked at, but for an engine that does not have direct cylinder
> fuel injection, your numbers are pretty good. Small changes in
> airflow velocity could certainly make the distribution change. All
> in all, I would say things are going well!
>
> Thanks again for letting us know what is happening.
>
> Keep in mind that the actual temperatures attained are immaterial.
> It is the split between when they go lean that is important.
>
> That is why Al Hundere always refused to have the actual
> temperature displayed on his ALCOR instruments.
>
> Happy Skies,
>
> Old Bob
>
> In a message dated 8/19/2009 9:29:45 A.M. Central Daylight Time,
> lynnmatt@jps.net writes:
> --> JabiruEngine-List message posted by: Lynn Matteson
> <lynnmatt@jps.net>
>
> I flew the GAMI Lean Test(s) today, and found the following: All
> temps are in degrees F.
>
> Three different tests, flown at 4500', 6000-6300', and
> 6500-7200'....these were supposed to be at a fixed altitude, but you
> know how that goes, when you're busy writing things down, and nobody
> else to keep track of the airplane.
>
> Cutting right to the numbers, I showed a .1 gph spread on one test,
> and two tests of .3 gph spread. Looking at the results, the rear
> cylinders usually peaked first, and were in the 1387- 1430 range when
> they did.
>
> The front two cylinders usually peaked last, and were in the
> 1333-1352 range when they did peak. In one test, at 2750 rpm
> (6000-6300'), #'s 1 and 3 peaked first at 2.8 gph, and 2 and 4
> followed at 2.7 gph. Rpm had dropped down to 2700 during this test.
> CHT's not recorded during the 1&3 peaks, but they were (1) 298, (2)
> 306, (3) 305, (4) 316.
>
> At 2800 rpm (6500, wandering up to 7200'), #'s 3 and 4 peaked at 1430
> and 1410 resp., at 3.2 gph, and 1 and 2 at 1333 and 1352 resp., at
> 2.9 gph. Rpm went up to 2830. CHT's were (same order, 1,2,3,4)
> 321,323, 311,and 322 when the last 2 cylinders peaked
>
> At 2860 rpm (4500'), #3 peaked at 1431 F. at 3.1 gph, #4 at 1402 at
> 2.9, and #'s 1 and 2 at 1351 and 1337 respectively at 2.8 gph. Rpm
> stayed the same, as near as I could tell. This ws the first test, and
> I wasn't quit up to the task as yet. Once I got going, the recording
> was a little better, but still not great.
>
> These findings pretty much parallel the findings that I recorded with
> the Bing carb, in that just a little rpm change can swap the hot EGT
> from one side to another, or even on the same side. I've even seen
> the higher numbers pass each other on the way up and down. Sometimes
> I've seen #2 (left front) get up to the 1400's, but it doesn't seem
> to last long. This tells me that both the Bing and the Rotec TBI
> suffer from manifolding problems, or maybe just plain lack of
> turbulence or even distribution of the fuel.
>
> Overall, I don't think these numbers are too bad, and the spread of .
> 1 to .3 is better than the GAMI target of .5, but this is a smaller
> engine, and the fuel doesn't have to go as far. That might be a naive
> way to look at it, but it seems to make sense (so it's probably
> wrong). : )
>
> There ya go, engineers, have at it, and tell me what I missed. I plan
> on running another test or more, so if anybody sees something I
> should do different, holler.
>
>
> Lynn Matteson
> Kitfox IV Speedster, taildragger
> Jabiru 2200, #2062, 739.7 hrs
> Sensenich 62"x46" Wood prop
> Electroair direct-fire ignition system
> Rotec TBI-40 injection
> Status: ==============================================
> ================================================ -
> MATRONICS WEB FORUMS
> ================================================ - List
> Contribution Web Site sp;
> ==================================================
>
>
> www.matronics.com/contribution _-
> ===========================================================
Message 5
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| Subject: | Re: Results of GAMI Lean Tests |
Yup, I've been warned that a perfectionist is someone who doesn't
know when good enough is good enough.
Lynn Matteson
Kitfox IV Speedster, taildragger
Jabiru 2200, #2062, 739.7 hrs
Sensenich 62"x46" Wood prop
Electroair direct-fire ignition system
Rotec TBI-40 injection
Status: flying
do not archive
On Aug 19, 2009, at 4:25 PM, BobsV35B@aol.com wrote:
> Good Afternoon Lynn,
>
> Sounds to me like you are way ahead of anything I might suggest.
>
> It is a two pronged problem. The first thing is to get equal air to
> each cylinder and the second thing is to get equal fuel to each
> cylinder.
>
> Messing with the flow has the potential of upsetting the balance or
> making it better. I guess that is why we call it experimental!
>
> Keep that information coming!
>
> Remember that the mortal enemy of good enough is the search for
> perfection.
>
> Happy Skies,
>
> Old Bob
>
> In a message dated 8/19/2009 3:01:47 P.M. Central Daylight Time,
> lynnmatt@jps.net writes:
> <lynnmatt@jps.net>
>
> Got any ideas, Bob, on how to change the airflow velocity? I'm all
> ears. I'm envisioning a hacksaw cut into an intake tube and welding
> in a steel plate of some size to slow down some of the flow, and
> divert it to other tubes, but that's the shade-tree guy coming out of
> me.
>
> Realistically, though, maybe a more centralized carb, with equal-
> length runners would help, but the oil pan is right in the
> way....hmmmm, dry sump? Now we're going the way of Rotax, and that's
> not good.
>
> Of course, individual squirters into each intake tube, right at the
> head would help, and I happen to know of a place out west that is
> good at making these things. : ) The funny part of that idea is
> that's the direction I was thinking of going when I learned about the
> Rotec TBI.
>
> I sure wish I had a junk Jabiru engine I could play around with, to
> help visualize some ideas, and not have to spend so much time with my
> cowl off, "imagineering" things.
>
> Lynn Matteson
> Kitfox IV Speedster, taildragger
> Jabiru 2200, #2062, 739.7 hrs
> Sensenich 62"x46" Wood prop
> Electroair direct-fire ignition system
> Rotec TBI-40 injection
> Status: flying
>
>
> On Aug 19, 2009, at 10:59 AM, BobsV35B@aol.com wrote:
>
> > Good Morning Lynn,
> >
> > Thanks for the data. I agree that the .1 split seems great.(As in
> > very good) At your fuel flows, I think a split of .3 needs to be
> > looked at, but for an engine that does not have direct cylinder
> > fuel injection, your numbers are pretty good. Small changes in
> > airflow velocity could certainly make the distribution change. All
> > in all, I would say things are going well!
> >
> > Thanks again for letting us know what is happening.
> >
> > Keep in mind that the actual temperatures attained are immaterial.
> > It is the split between when they go lean that is important.
> >
> > That is why Al Hundere always refused to have the actual
> > temperature displayed on his ALCOR instruments.
> >
> > Happy Skies,
> >
> > Old Bob
> >
> > In a message dated 8/19/2009 9:29:45 A.M. Central Daylight Time,
> > lynnmatt@jps.net writes:
> > <lynnmatt@jps.net>
> >
> > I flew the GAMI Lean Test(s) today, and found the following: All
> > temps are in degrees F.
> >
> > Three different tests, flown at 4500', 6000-6300', and
> > 6500-7200'....these were supposed to be at a fixed altitude, but you
> > know how that goes, when you're busy writing things down, and nobody
> > else to keep track of the airplane.
> >
> > Cutting right to the numbers, I showed a .1 gph spread on one test,
> > and two tests of .3 gph spread. Looking at the results, the rear
> > cylinders usually peaked first, and were in the 1387- 1430 range
> when
> > they did.
> >
> > The front two cylinders usually peaked last, and were in the
> > 1333-1352 range when they did peak. In one test, at 2750 rpm
> > (6000-6300'), #'s 1 and 3 peaked first at 2.8 gph, and 2 and 4
> > followed at 2.7 gph. Rpm had dropped down to 2700 during this test.
> > CHT's not recorded during the 1&3 peaks, but they were (1) 298, (2)
> > 306, (3) 305, (4) 316.
> >
> > At 2800 rpm (6500, wandering up to 7200'), #'s 3 and 4 peaked at
> 1430
> > and 1410 resp., at 3.2 gph, and 1 and 2 at 1333 and 1352 resp., at
> > 2.9 gph. Rpm went up to 2830. CHT's were (same order, 1,2,3,4)
> > 321,323, 311,and 322 when the last 2 cylinders peaked
> >
> > At 2860 rpm (4500'), #3 peaked at 1431 F. at 3.1 gph, #4 at 1402 at
> > 2.9, and #'s 1 and 2 at 1351 and 1337 respectively at 2.8 gph. Rpm
> > stayed the same, as near as I could tell. This ws the first test,
> and
> > I wasn't quit up to the task as yet. Once I got going, the recording
> > was a little better, but still not great.
> >
> > These findings pretty much parallel the findings that I recorded
> with
> > the Bing carb, in that just a little rpm change can swap the hot EGT
> > from one side to another, or even on the same side. I've even seen
> > the higher numbers pass each other on the way up and down. Sometimes
> > I've seen #2 (left front) get up to the 1400's, but it doesn't seem
> > to last long. This tells me that both the Bing and the Rotec TBI
> > suffer from manifolding problems, or maybe just plain lack of
> > turbulence or even distribution of the fuel.
> >
> > Overall, I don't think these numbers are too bad, and the spread
> of .
> > 1 to .3 is better than the GAMI target of .5, but this is a smaller
> > engine, and the fuel doesn't have to go as far. That might be a
> naive
> > way to look at it, but it seems to make sense (so it's probably
> > wrong). : )
> >
> > There ya go, engineers, have at it, and tell me what I missed. I
> plan
> > on running another test or more, so if anybody sees something I
> > should do different, holler.
> >
> >
> > Lynn Matteson
> > Kitfox IV Speedster, taildragger
> > Jabiru 2200, #2062, 739.7 hrs
> > Sensenich 62"x46" Wood prop
> > Electroair direct-fire ignition system
> > Rotec TBI-40 injection
> > Status: ==============================================
> > ================================================ -
> > MATRONICS WEB FORUMS
> > ================================================ - List
> > Contribution Web Site sp;
> > ==================================================
> >
> >
> >
> >
> > www.matronics.com/contribution _-
> >
> ======================================================================
> =========================== Use utilities Day
> ================================================ -
> MATRONICS WEB FORUMS
> ================================================ - List
> Contribution Web Site sp;
> ==================================================
>
>
> www.matronics.com/contribution _-
> ===========================================================
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| Subject: | Jab 3300 vs Rotax 912ULS performance - technical interpretation |
Hi folks. Trying to determine the increase in performance I could
expect by using a Jab 3300 rather than a Rotax 912ULS in my soon to be
built CH750 and would appreciate some technical help with the numbers.
The numbers I get are as follows
Jabiru 3300 @ 3300 RPM, 123 HP, 200 ft lbs, 178 lbs "ramp" weight,
$24500 with CH750 FWF
Rotax 912ULS @ 5800 RPM, 100 HP, 94 ft lbs - 225 ft lbs with 2.43
reduction gear, 156 lbs "ramp" weight, $20000 with CH750 FWF
Was I correct to calculate the shaft torque for the Rotax by
mulitpllying by the reduction gear ratio?
Would some power loss but not torque? Ie the Rotax max HP at shaft
will actually be a bit less due to friction losses but torque will be
same.
Appreciate technical advice on these numbers ie what does higher HP
but lower torque in Jab actually mean in real life? Will the Jab
give faster cruise but the Rotax more pull under heavy loads?
I am particularly interested in what the numbers would mean for float
operations.
Thanx gang.
Cpt Vic
Building Zenair CH750
Whitehorse Yukon
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Ditto.....My book says DO NOT USE AUTOMOTIVE OILS.USE AVIATION GRADE OIL MADE for
air cooled engines.also SAYS AERO SHELL 100 or 15-50.
These cost to much for me to experiment with something NOT recommended by Jabiru.
chris ambrose
M3X Kolb/A2200 Jab 48.7 hrs+
N327CS
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=258764#258764
Message 8
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| Subject: | Re: Results of GAMI Lean Tests |
Lynn wrote
> Three different tests, flown at 4500', 6000-6300', and
> 6500-7200'....these were supposed to be at a fixed altitude, but you
> know how that goes, when you're busy writing things down, and nobody
> else to keep track of the airplane.
Lynn
If you're not familiar with Waiter and his data logger software, I suggest that
check out
http://www.iflyez.com/EFISRecorder.shtml
With Waiter's software, a low level laptop can give second by second recording
of your EFIS data. I believe the software is free. I'm planning to use it for
my phase 1 tests ... when I get to that point.
Terry
--------
Terry Phillips
Corvallis, MT
ttp44<at>rkymtn.net
Zenith 601XL/Jab 3300 slow build kit - Tail feathers done; working on the wings.
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=258784#258784
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