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New Eggenfellner Performance Numbers

Good info

Engine 5376 RPM! Hooche Moma! 201 mph at 8.9 gal/hr is not bad.

I guess a typical cruise mode will not be at full throttle:
prop 1800 rpm
eng 4608 rpm
eng 21.0 map
eng 8.2 FF
tas 190 mph

To put that into perspective a 160HP RV-7A at 75% cruises at 190 mph.

Fuel flow should be around 8.5 ga/hr at 2,400 rpm (ref. Lyc diagram IO-320 B,D part throttle fuel consumption). So the H6 is getting 0.30 gal/hr better fuel econ from my rough numbers @ 190 mph.

A Sam James cowl on the Lyc, would go faster (or burn less fuel) than Van's stock cowl. Assume max gain for SJ cowl on a Lyc RV-7A is 8 mph, in cruise say 4 mph. The Lyc with electronic ignition gets you 4% decrease in fuel flow, down to 8.1 gal/hr, plus a mph or two. The SJ cowl would be a notch up on speed (4 mph) and efficency, but with the stock numbers the H6 compares favorable with the 160 HP Lyc in cruise.

However interestingly enough at full RPM, 5376, even if you would not fly that way all the time the 201 mph at 8.9 gal/hr is like a 180 HP Lyc at 75% power at 9.2 gal/hr. Interesting. Again this is a stock Lyc and cowl. It appears the H6 is producing about what a 180HP Lyc is making and slightly better spacific consumption at full RPM. Again a EI would give the Lyc the same FF and the SJ cowl gets you a slight speed edge.


What does that mean? The new drive is doing good from these prelim numbers. :) It looks like the H6 is a true 180 HP engine (equivalent Lyc at the prop). It also looks like it is getting similar speed and fuel burn. In fact the burn to stock Lyc numbers from charts is slightly better. However with EI and SJ cowl the Lyc will have a slight advantage in both speed and econ.

Good for Eggenfellner. The big question is would one want to cruise at 5376 RPM. Also weight was not reported but suspect it is hefty affecting stall speed, takeoff/landing dist and climb rate.

I would like to know the empty weight of the H6 set-up on the RV-7 with the new prop and reduction.

Good info thanks George
 
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gmcjetpilot said:
I would like to know the empty weight of the H6 set-up on the RV-7 with the new prop and reduction.
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"QUESTION: How much does the firewall forward package weigh?

The H-6 engine has the same firewall forward weight as the IO-360. The total is 350 for the engine and 420 for the firewall complete package. Add 30 lb to this for a supercharged H-6 model."

http://www.eggenfellneraircraft.com/FAQ.htm

I was wondering also....
 
Thank you

Ward Johnson said:
"QUESTION: How much does the firewall forward package weigh?

The H-6 engine has the same firewall forward weight as the IO-360. The total is 350 for the engine and 420 for the firewall complete package. Add 30 lb to this for a supercharged H-6 model."

http://www.eggenfellneraircraft.com/FAQ.htm

I was wondering also....
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I hear you Ward, however I have doubts. Why?

I asked Jan this and that was what he said, about the weight of a IO360. He also said the H6 weighed 40 lbs more than 2.5L, but in the same breath he acknowledged that 1140 lbs was a typical RV-7, 2.5L empty weight. The two don't jive.

If you look at the empty weight of Eggenfellner 4 cyl 2.5L installations, they already weigh the same or more (by quite a bit in some cases) than a IO360 (200HP). So I think the H6 is going to come in at least 40 lbs more than IO360's, since the 2.5L already weighs what IO360 RV's weigh.

If you go to Dan C's excellent W&B tabulation of finished RV's you will see that the eggenfellner (2.5L) RV's weight compares and even exceeds RV's with the heavy IO360. http://www.rvproject.com/wab/

That is the same conclusion I came to. One Egg/MT prop RV-7 weighed 1140 lb. Of two RV-7's and two RV-7A's with IO360's, their weight came in at 1103 to 1141 lbs.

Now take an extra 40 lb plus another 30 lbs for supercharged, that is quite a bit more. It will be interesting to get the actual empties. The supercharged version lets say will weigh 1210 lbs. That leaves 590 lbs for payload+fuel. That is under 400 lbs for pilot/pax + bags. Of course there is the time honored method of arbitrarily upping the max allowed gross. Dual aerobatics will be a bit of an issue. You can't fudge with that weight. G
 
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Actual innovation

rv6ejguy said:
J175 knots TAS on 8.9 gals./hr. at 8500 feet, 2100 prop rpm and 21 inches MP.
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I think it is interesting to point out that Eggenfellner is trying to take an interesting and innovative tack in the small piston market, and that is the "slow" turning prop. Notice that max speed here is with the prop spinning at 2100. A nice cruise has the prop at 1700 or less.

I don't know how this will eventually work out, but I have to commend him for trying out this kind of fairly radical idea in our marketspace.
 
It would appear that all numbers are at WOT (21 inches) and that only rpm was varied via prop pitch. On an auto engine there is a significant change in hp with rpm. Bottom line here is that the new H6 configuration is competitive in speed and fuel flow to most O-360 powered -7As that I'm aware of. Anyone else doing over 175 knots TAS on less than 8.9 gallons hr. in real life?

Weight wise it would be interesting to know however this prop is at least 30 lbs. lighter than a Hartzell C/S.
 
rv6ejguy said:
On an auto engine there is a significant change in hp with rpm.
Click to expand...
?? don't you mean "any" engine (of the rotating variety)? hp=tq x rpm/5252


rv6ejguy said:
Anyone else doing over 175 knots TAS on less than 8.9 gallons hr. in real life?
Click to expand...
diesel Velocity. 6.7g/hr@180ktas. but that's another story. Jan is doing well with the H6.
 
rv8ch said:
I think it is interesting to point out that Eggenfellner is trying to take an interesting and innovative tack in the small piston market, and that is the "slow" turning prop. Notice that max speed here is with the prop spinning at 2100. A nice cruise has the prop at 1700 or less.

I don't know how this will eventually work out, but I have to commend him for trying out this kind of fairly radical idea in our marketspace.
Click to expand...

I agree. SMA did this on their diesel using large MT prop (direct drive). The engine ran full power at 2300.

Any info on the specs of that prop on the Egg? I suspect he'd be even faster with large diameter 2-blade in the 76" range since tip speeds are not an issue at 2100. 80" would be ideal but ground clearance becomes a factor above 76".
 
Reality Check

Please don't flame me; I'm not calling anyone names.

However, if the Egg is getting 70% (21" / 29.92" MAP ) of 180 HP (126 HP) on 8.9 GPH then it's doing it with a BSFC of .4227 US gallons per HP per hour. That's reasonable and a good Lyc / Cont / etc. can equal it with proper operation. But, if the correct divisor is lower than 29.92 due to intake path losses, then the claimed BSFC verges towards eyebrow-raising.

See: http://www.prime-mover.org/Engines/GArticles/bsfc.html or just Google "BSFC".

If that aircraft is really doing 175 kts TAS on 8.9 GPH, then it is a testament to the airframe, the cowl & cooling drag, the pants and the drive system. We all know, don't we, that to multiply speed by 1.X we need to increase HP by approximately 1.X cubed? (Kevin Horton or George, feel free to correct me).

In other words, if his numbers are completely acccurate, Jan has a VERY efficient airplane. I don't know that it says much about the engine except that you need a reduction drive, a well optimized prop and perhaps water cooling to produce this result this way. And don't forget that all other things being equal, Jan's configuration loses some HP to the belt drive as compared to direct drive.

Can anyone figure out what the prop efficiency would have to be?

BTW, George - If a James cowl is worth 8 mph top-end, it's worth a heck of a lot more than 4 mph at cruise. Also, I once figured out it will be worth about 12 HP on my 7A that has not flown yet. That's close to 0.5 GPH.

h
 
Just a couple of things to add to the mix:

The supercharged version of the H6 is made for RV10s.. they don't recommend the supercharged version for a -7(A).

Jan said in a recent email to the eggenfellner mailing list that the actual prop once it is out of development will be 76" and could be cut down to 72" if desired.
 
First on the prop, this is a 4 blade. I'd see no reason to make this any larger in diameter. Jan wants it efficient over a wide power setting range. The whole point of turning it slow is to keep it efficient. This is an option with the correct redrive ratio. Most turboprops are turning props very slow compared to direct drive piston engines in ther quest for max efficiency and low mach numbers. I was told by MT on my RV10 Sube that dropping max prop rpm to 2550 from 2700 by using a different governor would increase prop efficiency 2-3% in cruise. This has been comfirmed by at least one other MT user through flight testing on a canard design.

Most auto engines do not have such a flat torque curve as a Lyco, therefore 1500-2000 engine rpm may impact hp than 300-400 on a Lyco.

Typically, Subaru engines are fitted with very large throttle bodies and runners (my 2.2 has a 60mm TB) and show almost ambient MAP at WOT. The H6 in its present state with VVT is very efficient compared to fixed cam timing engines.

Some of the modern high CR direct injection auto engines have demonstrated SFC figures below .40 at or near torque peak rpm. Most conventional auto engines are in the .43 to .46 range at cruise power settings.

I think there are too many variables present here to speculate about hp. If the data presented is accurate, Jan has closed the gap on the fuel flow vs. speed argument on the auto vs. Lyco debate considerably and my hat is off to him. I frankly thought it would take more development time to accomplish this. We should also be thanking beta testers Tom Moore and Robert Paisley as well for their tireless devotion testing many of Jan's new parts.
 
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Sounds right to me

hevansrv7a said:
BTW, George - If a James cowl is worth 8 mph top-end, it's worth a heck of a lot more than 4 mph at cruise. Also, I once figured out it will be worth about 12 HP on my 7A that has not flown yet. That's close to 0.5 GPH.
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No argument from me buddy. Sounds good. My 4 mph number was a low low ball to be conservative when trying compare the H6 vs. Lyc numbers, but you are right. Also excellent real world common sense evaluation of the data. I suspended disbelief and just went on the assumption they are valid, eyebrow's in down and locked postition. With any engineering data you have put it through the "reasonable meter" and show repeatable results.

The props comments are true. Slow turning props are efficent, and you could go to larger dia. Cool ideas. If prop is designed properly for the fwd airspeed and low RPM, it's a very efficent way to go. Even a Lyc and Hartzell can do that and get great gas milage by dialing down the RPM loooow. However with a direct drive engine low RPM is less HP. Still efficent but slower. I also applaude his efforts.
emoticon-applaud.gif


G
 
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I have always thought that the Sub is a good option but have recently been put off by a Sub owner. The owner of this Eggenfeller engine [for a Glastar] tells me that the service of Eggenfeller is not good. He also said that Jan Eggenfeller was abrupt and rude and even put the phone down on him. I know this fellow and he is a eazy going type person, so am very inclined to believe what he says.

He also says that J Eggenfeller edits all the forum posts on his forum site.

This has now completely scared me away from considering a Eggenfeller Sube.
Has anyone else have something to add before I totally forget about the Sube??

Thought I would post here as many Sube owners would be reading this thread.
 
Subaru

rv72004 said:
I have always thought that the Sub is a good option but have recently been put off by a Sub owner. The owner of this Eggenfeller engine [for a Glastar] tells me that the service of Eggenfeller is not good. He also said that Jan Eggenfeller was abrupt and rude and even put the phone down on him. I know this fellow and he is a eazy going type person, so am very inclined to believe what he says.

He also says that J Eggenfeller edits all the forum posts on his forum site.

This has now completely scared me away from considering a Eggenfeller Sube.
Has anyone else have something to add before I totally forget about the Sube??

Thought I would post here as many Sube owners would be reading this thread.
Click to expand...
I thought you were going with the XP360?

A couple of points. On Eggenfellner's forum, there are two categories of users - those that have bought the engine, and those that have not. Once you've bought the engine, there is no moderation on the posts - they go right up. For the rest, they get moderated. He said he implemented this policy because there were some people who had no intention of buying the engine but were spending a lot of time bashing his package. I have no idea how many posts are removed or edited, if any.

Buying an engine from a single source supplier has risks. What if Jan gets hit by a truck while jogging to work? What would happen to his company? What if he just goes out of business? These are risks that I considered, and decided they were acceptable risks, since most of the engine is just a standard, stock Subaru, and the other parts that have been manufactured can be re-built at a good machine shop.

Each person has to evaluate their tolerance for risk of this type, and make their own decision.
 
I have an H6 from Jan, and I'm very satisfied with the way he handles his business. The only "problem" I've had is his getting a bit behind schedule on engine deliveries. My December engine was delivered in February, but that was not really a big issue. Jan has always been very responsive to questions or concerns that I've had along the way. I went down to his shop about a year ago to take a motor mount to him, and my Father and I had a very nice visit with him (and a very fun and fast ride in his car to lunch and back) and he was very willing to answer questions and such.
I wouldn't hesitate to do business with him anytime.
As far as parts support in the future should something happen that caused him to go out of business, with the exception of the reduction drive, the engine package looks like it would be fairly easy to get parts for. The engine itself is stock Subaru, and the external "aircraft" parts could be duplicated by any competent fabricator.
 
Group,
It seems that there are a large number of people that simply don't like to see people become successful. Jan's problem is typical, once you have become the "best available" package there is a number of people that just want to knock you off your perch. I do not own, but have close association with 2 people who have Eggenfellner engines. One is Tom Moore, the demo unit for the new belt drive. He is very happy with his Egg motor package. He will also confidently fly far from home in the plane. (The confidence factor is important IMO.) Tom flew to a meeting of our EAA chapter in Livermore CA. at night without worry. (his words) His home is in northen Oregon. That is a ringing endorsement of his feel for the engine.
My other friend has an earlier 2.5 L engine in his RV-9 which is near flying. He has never had problems getting his questions answered. MOST people believe Jan is a top notch guy, some will always be dissatisfied, others indifferent. If you think Eggenfellner has poor customer service you probably won't like anyone's. As usual the typical disclaimers apply; YMMV, PDOACC, ETC.
Bill Jepson
 
I don't find my posts edited on Jan's Yahoo site but I understand the need to sometimes. If you saw the bashing Jan took on some of the other forums a few years back, you might understand. Every business has problems no matter how well managed and there will always be some customers who are not happy.

Late deliveries have been part of the picture unfortunately for all three of the main Subaru engine companies in the last few years. Jan is always trying to deliver a better product so the package is never frozen for long. Updates and changes create some of these delays but you are probably getting something better in the end.

I don't own an Eggenfellner package but have dealt with Jan on some previous collaborations. He seems like an innovative, enthusiastic guy wanting to give people a viable alternative to traditional aircraft engines. Has he made mistakes? Sure, as have we all. I doubt any company has a 100% customer service rep but Jan seems to have a very high percentage of satisfied ones.
 
Note from the forum owner

Yukon said:
H,
Don't worry, you won't get flamed! They don't know what you are talking about!!!! I do, though, and I'm not afraid to put it in plain English. Complex propulsion systems suffer from inefficiencies that can only be compensated for with an intricate system of smoke and mirrors!
John
RV-9 QB Lycoming
Click to expand...
Gentlemen,

I'd like to remind everyone that new forum usage rules are now in place. I want the tone civil and the mood respectful. I will take action, action of the perminantly-banned kind, if this does not occur from this point forward.

Doug Reeves
Forum Owner
 
Just lurking on in this post, quietly learning about the Egenfellner packages and seeing an intelligent discussion marred by one post, got me alarmed... not typical of my limited experience on this forum... but

I'm glad to see Delta Romeo's post above... hopefully this can get back to a discussion of technical merrit, real world data, and actual experiences with an interesting product and its developer.

Tom
 
My numbers are close

RV-7A. SJ cowl, plenum and pants. Superior 180 hp FI, Catto 3-blade course pitch.

169 kts 9.0 ghp LOP WOT 8500' DAlt. This is 75% using Walter Atkinson's formula for HP from FF when LOP. It will do 175 kts for another GPH.

Jan's doing better if his numbers are as accurate as mine (GPS 3-way calibration of GRT TAS)
 
hevansrv7a said:
RV-7A. SJ cowl, plenum and pants. Superior 180 hp FI, Catto 3-blade course pitch.

169 kts 9.0 ghp LOP WOT 8500' DAlt. This is 75% using Walter Atkinson's formula for HP from FF when LOP. It will do 175 kts for another GPH.

Jan's doing better if his numbers are as accurate as mine (GPS 3-way calibration of GRT TAS)
Click to expand...

That's very nice but I believe the poster was looking for others flying the Egg engines with some real world numbers.
 
rv6ejguy said:
That's very nice but I believe the poster was looking for others flying the Egg engines with some real world numbers.
Click to expand...

Here are some numbers I posted on the EGG forum in August of 2004.
(note: I have since come to believe the MT-7 prop is not optimal for the engine. The MT-7 was certified with the Cessna 152 on 27APR92. How it came to be the prop of choice with the Subaru engine for a couple years I know nothing about, except as I say, I do not believe it is optimal for the H6 engine. The new Sensenich prop would produce different numbers.)

At 12,500', OAT 53?F.

RPM 2600/4830 (prop/engine)
BURN = 10.1
TAS = 148 KTS (170 MPH)
MPG = 16.83 (Still Air)

RPM 2500/4590
BURN = 9.3
TAS = 146 (168)
MPG = 18.06

RPM 2400/4350
BURN = 8.5
TAS = 144 (166)
MPG = 19.52

RPM 2300/4160
BURN = 7.8
TAS = 140 (161)
MPG = 20.64

RPM 2200/3970
BURN = 7.1
TAS = 135 (156)
MPG = 21.97

RPM 2100/3780
BURN = 6.8
TAS = 133 (152)
MPG = 22.35

RPM 2000/3580
BURN = 6.0
TAS = 127 (146)
MPG = 24.33

RPM 1900/3400
BURN = 5.5
TAS = 125 (144)
MPG = 26.18

RPM 1800/3200
BURN = 5.1
TAS = 122 (141)
MPG = 27.64

RPM 1700/3090
BURN = 4.9
TAS = 114 (132)
MPG = 26.93

The 2600 2500 2400 2300 2200 RPM numbers at 8,500' are as follows:

RPM 2600/4830
BURN = 12.2
TAS = 151 (174)
MPG = 14.26

RPM 2500/4620
BURN = 11.2
TAS = 152 (175)
MPG = 15.62

RPM 2400/4340
BURN = 10.1
TAS = 149 (171)
MPG = 16.93

RPM 2300/4160
BURN = 9.6
TAS = 146 (168)
MPG = 17.5

RPM 2200/3970
BURN = 8.6
TAS = 141 (162)
MPG = 18.83

I recorded numbers down through 1700 RPM again and they were slightly less efficient than the previous flight, probably due to a colder temperature and heavier airplane with full tanks. I did not record numbers at 2700 RPM because the engine still stumbles a bit at that RPM. I do not know what is causing it. The engine just hesitates a bit now and then at 2700. It is smooth at all other RPMs, the smoothest being 2300.

Today I finally determined what was causing a strange noise at 1700 RPM - it is the left muffler hanger. It needs to be tightened. When I put my shoe on it on the cabin floor, it became quiet. That was a good feeling as that noise had been of some concern.

As stated in a previous message, there's some work to be done to reduce drag. This airplane ought to going faster than it is at the top end.

dd
RV-7A
H6
 
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