If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below. |
|
|
Thread Tools | Display Modes |
#11
|
|||
|
|||
Engine configuration
Have you ever read Lycoming's recommendations for leaning their engines?
The engine runs as cool at 25 degrees lean of peak as it will 25 degrees rich of peak. It isn't as smooth, and it has that lean "bark", but it doesn't hurt the engine if the power setting is below 75 percent. The engine runs cleaner. We had a customer once who was scared to lean his engine correctly. He leaned just enough to keep the engine smooth at altitude. One day he took off from a mountaintop airport and had two intake valves seize. Luckily, there was another airport in the valley below, so the airframe survived fine. But his fear of leaning sure made a mess of that Lycoming. "Ron Webb" wrote in message ... Yea, I've heard of it. You won't catch me, or anyone I know trying it for very long. Experimenting on a $15K IO360 is not something I am comfortable with. Never heard of "agressive leaning" of air cooled aircraft engines? Below peak power it is very viable -- Posted via a free Usenet account from http://www.teranews.com |
#12
|
|||
|
|||
Engine configuration
On Fri, 21 Dec 2007 17:19:51 -0900, "Ron Webb"
wrote: Yea, I've heard of it. You won't catch me, or anyone I know trying it for very long. Experimenting on a $15K IO360 is not something I am comfortable with. Never heard of "agressive leaning" of air cooled aircraft engines? Below peak power it is very viable -- Posted via a free Usenet account from http://www.teranews.com Well beyond the experimentation phase. Very well documented. Actually RECOMMENDED on engines designed for 87 octane when running 100LL. Keeps the valves from hanging from "lead poisoning" Also greatly extends cruise range. This was investigated and proven by of all people, Charles Lindburg, WAYYYYY back then. Also see: http://www.megginson.com/blogs/lahso...12/23/leaning/ -- Posted via a free Usenet account from http://www.teranews.com |
#13
|
|||
|
|||
Engine configuration
On Fri, 21 Dec 2007 17:45:28 -0900, "Ron Webb"
wrote: Blanton's claim that you could get 230 reliable HP out of it was vigorously debated. With open intake, open exhaust, ported heads, big cam and carb, and forged rods and pistons for reliability my desktop Dynamometer program shows over 330 HP at 6500 RPM, and 278 HP at a more sedate 5000 RPM possible, without forced induction. Dyno2000 is usually very close to right. Blanton claimed 260 HP, derated to 230 HP. I doubt that anyone will argue with that statement. The problem isn't in getting that power out, it is with getting the heat out, even with water cooled engines. An engine, to give 2000 hours MTBF (well, with a 2000 hour TBO, you would want the MTBF significnatly longer) needs more than great tuning. You did say reliable; remember that an airplane engine typically will be expected to operate at 75% to 85% power for hours at a time; an automobile engine in a 2500 lb car (think Cessna 182 or Cirrus) running at 60 MPH probably averages 20 HP. I cannot prove my automobile numbers, and they may be all wet. Look at highly tuned auto engiens ... NASCAR probably gets 800 HP from 350 cu-in ... and they last 4 or 5 hours. Drag racers likely get over double that, but their engines last minutes. Contrary to what many think, most accept that the "obsolete" Lyconental engines are pretty good products, making below 0.4 lb/hp-hr SFC ... better than many cars. That's EFFICIENT! I'd bet that if an auto engine would out perform Lycontental, we'd see them certified and in use; the only water cooled engine I know of in certified applications is the water cooled HEAD engine by Rotax. They get 80 HP @ 5500 rpm from 74 cu-in ... and a 1500 hr TBO. They are not cheap to build, either; even the uncertified ones are in the $15,000 range. Business wants to make money; if you can build a 230 HP engine that will reliably give 2000 hours in an airplane and sell it for $10,000, I'd bet that getting it certified and insured will be a piece of cake .... certified, it is probalby over a $30,000 sale. But my own opinion ... if it were that easy, it would have been done. |
#14
|
|||
|
|||
Engine configuration
"GeorgeB" wrote I'd bet that if an auto engine would out perform Lycontental, we'd see them certified and in use; the only water cooled engine I know of in certified applications is the water cooled HEAD engine by Rotax. They get 80 HP @ 5500 rpm from 74 cu-in ... and a 1500 hr TBO. They are not cheap to build, either; even the uncertified ones are in the $15,000 range. Business wants to make money; if you can build a 230 HP engine that will reliably give 2000 hours in an airplane and sell it for $10,000, I'd bet that getting it certified and insured will be a piece of cake ... certified, it is probalby over a $30,000 sale. But my own opinion ... if it were that easy, it would have been done. It has been, by many people. Many V-8's and V-6's are well past 2,000 hours, with no rebuilding necessary. Orenda did it, and certified it, but designed their own V-8, but it is not much different than GM V-8's. It might be time to trot out the blog on how GM torture tests it's engines, before a design goes into production. I don't have the file handy, but perhaps someone else does. Without the file handy, it is an easy jump to say that their duty cycles and punishment make a certification test run look like child's play. The problem with auto engine conversions is seldom the engine. It is usually in the accessories, or the prop speed reducers. There are good products out there for those, too. One has to only put them together. -- Jim in NC |
#15
|
|||
|
|||
Engine configuration
Here's one current example of a very well done Ford 5.0L V8. There are MANY
more. http://www.haaspowerair.com/index.html The FAA, and the legal system conspire to make selling these things an unprofitable enterprise...but it can be done - even by an individual in his garage...as proven thousands of times. It has been, by many people. Many V-8's and V-6's are well past 2,000 hours, with no rebuilding necessary. Orenda did it, and certified it, but designed their own V-8, but it is not much different than GM V-8's. It might be time to trot out the blog on how GM torture tests it's engines, before a design goes into production. I don't have the file handy, but perhaps someone else does. Without the file handy, it is an easy jump to say that their duty cycles and punishment make a certification test run look like child's play. The problem with auto engine conversions is seldom the engine. It is usually in the accessories, or the prop speed reducers. There are good products out there for those, too. One has to only put them together. -- Jim in NC |
#16
|
|||
|
|||
Engine configuration
"Morgans" wrote in message ... "GeorgeB" wrote I'd bet that if an auto engine would out perform Lycontental, we'd see them certified and in use; the only water cooled engine I know of in certified applications is the water cooled HEAD engine by Rotax. They get 80 HP @ 5500 rpm from 74 cu-in ... and a 1500 hr TBO. They are not cheap to build, either; even the uncertified ones are in the $15,000 range. Business wants to make money; if you can build a 230 HP engine that will reliably give 2000 hours in an airplane and sell it for $10,000, I'd bet that getting it certified and insured will be a piece of cake ... certified, it is probalby over a $30,000 sale. But my own opinion ... if it were that easy, it would have been done. It has been, by many people. Many V-8's and V-6's are well past 2,000 hours, with no rebuilding necessary. Orenda did it, and certified it, but designed their own V-8, but it is not much different than GM V-8's. It might be time to trot out the blog on how GM torture tests it's engines, before a design goes into production. I don't have the file handy, but perhaps someone else does. Without the file handy, it is an easy jump to say that their duty cycles and punishment make a certification test run look like child's play. The problem with auto engine conversions is seldom the engine. It is usually in the accessories, or the prop speed reducers. There are good products out there for those, too. One has to only put them together. -- Jim in NC FWIW, My Chrysler 318 Cu In V8 just turned 8600 hours without any service other than oil changes and spark plugs. Of course, that's in a Jeep Grand Cherokee. As I understand it, the 318 is neither better or worse than other V8's. In the Jeep, it gets 20mpg at 60mph which is 3gph. That's 45hp @ 2100 RPM. It weighs about 545 pounds. If you insist on 200HP @ 4500rpm output at cruise, which you would want to do to justify all that weight, it might not last as long. Bill Daniels |
#17
|
|||
|
|||
Engine configuration
Bill Daniels wrote:
"Morgans" wrote in message ... "GeorgeB" wrote I'd bet that if an auto engine would out perform Lycontental, we'd see them certified and in use; the only water cooled engine I know of in certified applications is the water cooled HEAD engine by Rotax. They get 80 HP @ 5500 rpm from 74 cu-in ... and a 1500 hr TBO. They are not cheap to build, either; even the uncertified ones are in the $15,000 range. Business wants to make money; if you can build a 230 HP engine that will reliably give 2000 hours in an airplane and sell it for $10,000, I'd bet that getting it certified and insured will be a piece of cake ... certified, it is probalby over a $30,000 sale. But my own opinion ... if it were that easy, it would have been done. It has been, by many people. Many V-8's and V-6's are well past 2,000 hours, with no rebuilding necessary. Orenda did it, and certified it, but designed their own V-8, but it is not much different than GM V-8's. It might be time to trot out the blog on how GM torture tests it's engines, before a design goes into production. I don't have the file handy, but perhaps someone else does. Without the file handy, it is an easy jump to say that their duty cycles and punishment make a certification test run look like child's play. The problem with auto engine conversions is seldom the engine. It is usually in the accessories, or the prop speed reducers. There are good products out there for those, too. One has to only put them together. -- Jim in NC FWIW, My Chrysler 318 Cu In V8 just turned 8600 hours without any service other than oil changes and spark plugs. Of course, that's in a Jeep Grand Cherokee. As I understand it, the 318 is neither better or worse than other V8's. Wow, you have an hour meter in your Jeep. I never saw that on the options list! Matt |
#18
|
|||
|
|||
Engine configuration
"Matt Whiting" wrote in message ... Bill Daniels wrote: "Morgans" wrote in message ... "GeorgeB" wrote I'd bet that if an auto engine would out perform Lycontental, we'd see them certified and in use; the only water cooled engine I know of in certified applications is the water cooled HEAD engine by Rotax. They get 80 HP @ 5500 rpm from 74 cu-in ... and a 1500 hr TBO. They are not cheap to build, either; even the uncertified ones are in the $15,000 range. Business wants to make money; if you can build a 230 HP engine that will reliably give 2000 hours in an airplane and sell it for $10,000, I'd bet that getting it certified and insured will be a piece of cake ... certified, it is probalby over a $30,000 sale. But my own opinion ... if it were that easy, it would have been done. It has been, by many people. Many V-8's and V-6's are well past 2,000 hours, with no rebuilding necessary. Orenda did it, and certified it, but designed their own V-8, but it is not much different than GM V-8's. It might be time to trot out the blog on how GM torture tests it's engines, before a design goes into production. I don't have the file handy, but perhaps someone else does. Without the file handy, it is an easy jump to say that their duty cycles and punishment make a certification test run look like child's play. The problem with auto engine conversions is seldom the engine. It is usually in the accessories, or the prop speed reducers. There are good products out there for those, too. One has to only put them together. -- Jim in NC FWIW, My Chrysler 318 Cu In V8 just turned 8600 hours without any service other than oil changes and spark plugs. Of course, that's in a Jeep Grand Cherokee. As I understand it, the 318 is neither better or worse than other V8's. Wow, you have an hour meter in your Jeep. I never saw that on the options list! Matt It's in the vehicle computer but you have to have a scanner to see it. You'd be amazed at the information those black boxes keep on you. Bill D |
#19
|
|||
|
|||
Engine configuration
Ron Webb a écrit :
Here's one current example of a very well done Ford 5.0L V8. There are MANY more. I do not doubt there are MANY successful V8 engines in MANY airplanes flying MANY happy hours. ...as proven thousands of times. The problem is, MANY is not proving anything. What we would need is, HOW MANY such engines made it to TBO, and in HOW MANY clearly identified airplanes. Only a few hundreds would suffice...;-) Best regards, -- Gilles http://contrails.free.fr |
#20
|
|||
|
|||
Engine configuration
The problem is, MANY is not proving anything. What we would need is, HOW MANY such engines made it to TBO, and in HOW MANY clearly identified airplanes. Only a few hundreds would suffice...;-) And that's what the situation will not allow (for it's own reasons). When you can't field a standardized package, with known engineering behind it, you are stuck evaluating "backyard" prototypes, done by mostly amateurs, against the pro's with 30 year proven packages. It's just amazing that our stats are still competitive, even so. The NTSB database (http://www.ntsb.gov/ntsb/query.asp) has fields for homebuilt vs certificated aircraft. (though not engines). I've played with it quite a lot, and as best I can tell, the homebuilt industry has about 2x as many accidents per flight hour. Almost all of these are stupid stuff. When you do find a crash because of an engine failure, it's usually a poorly designed fuel feed, a PSRU belt broken, or a poorly designed cooling system causing an in flight overheat. Amateur engineering can be fatal. |
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
Engine configuration | Michael Henry | Home Built | 42 | December 20th 07 10:30 PM |
Engine configuration | cavedweller | Home Built | 7 | December 16th 07 01:23 AM |
V-22 Prop Configuration, 3-vs-4 blades | Don McIntyre | Naval Aviation | 23 | April 10th 06 03:23 AM |
T-2C Buckeye nav light configuration. | Mike W. | Naval Aviation | 14 | March 17th 05 07:05 AM |
Question about center-line push-pull engine configuration | Shin Gou | Home Built | 4 | June 7th 04 05:57 PM |