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#1
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![]() I well let Bob do the BObbed part but I do have a couple questions about the above post by the guy that said he talked to someone that changed engines. I find the numbers difference very hard to believe without knowing more facts. And this may have all been explained somewhere and I can't find the info. What are the power output comparisons? I find the difference between 100 fpm and 1500 fpm pretty astonishing difference and really find it hard to believe. Also from 12 gph to 8.8 gph and 5 faster cruise is also pretty hard to believe. I think that if the auto engine proponents are going to convince the unbelieving they need to at least give honest and true numbers. Jerry ++++++++++++++++++++++++++++++++++++++++++++++++ Jerry, "Astonishing" is putting it mildly. g Some of these auto conversion folks have got "religion". They are 'true believers" and are as brainwashed as they come. Nothing concerning the laws of physics need apply. Fer instance..... 8.8 gph suggests 105 horsepower. 12 gph suggests 145 horsepower. How does one go 5 mph faster on 40 less horsepower and likely with a heavier engine? Dunno. but if you are a 'TRUE BELIEVER', nothing is impossible. If anything they said added up... someone, somewhere would get one of these 'WONDER' conversions certified and in the process make such folks very, very wealthy. It's not even close to happening. The certification process is something that keeps these black magic artists in the shadows of reality... on web sites and newsgroups.... beckoning the next rube, guppy, wannabee or whatever. No question, there is a sucker born every minute. Just ain't ever gonna me.. or you, from what I have observed. Barnyard BOb -- if it sounds too good to be true, it is. |
#2
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BOb wrote:
Fer instance..... 8.8 gph suggests 105 horsepower. 12 gph suggests 145 horsepower. How does one go 5 mph faster on 40 less horsepower and likely with a heavier engine? Dunno. but if you are a 'TRUE BELIEVER', nothing is impossible. I cannot speak for this *particular* case, but in general one "goes 5 mph faster on 40 less horsepower" by reducing the drag (parasitic and/or induced). speculation mode=wild Perhaps the water-cooled auto conversion has less parasitic cooling drag than the original air-cooled engine. /speculation Russell Kent |
#3
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![]() Fer instance..... 8.8 gph suggests 105 horsepower. 12 gph suggests 145 horsepower. How does one go 5 mph faster on 40 less horsepower and likely with a heavier engine? Dunno. but if you are a 'TRUE BELIEVER', nothing is impossible. I cannot speak for this *particular* case, but in general one "goes 5 mph faster on 40 less horsepower" by reducing the drag (parasitic and/or induced). speculation mode=wild Perhaps the water-cooled auto conversion has less parasitic cooling drag than the original air-cooled engine. /speculation Russell Kent +++++++++++++++++++++++++++++++++ Perhaps.... Santa Claus will bring me a new Cessna Citation fer Xmas and the funds to operate it, too. g Barnyard BOb -- If it sounds to go to be true..... |
#4
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On Mon, 03 Nov 2003 21:35:45 -0600, You know who
wrote: I well let Bob do the BObbed part but I do have a couple questions about the above post by the guy that said he talked to someone that changed engines. I find the numbers difference very hard to believe without knowing more facts. And this may have all been explained somewhere and I can't find the info. What are the power output comparisons? I find the difference between 100 fpm and 1500 fpm pretty astonishing difference and really find it hard to believe. Also from 12 gph to 8.8 gph and 5 faster cruise is also pretty hard to believe. I think that if the auto engine proponents are going to convince the unbelieving they need to at least give honest and true numbers. Jerry +++++++++++++++++++++++++++++++++++++++++++++++ + Jerry, "Astonishing" is putting it mildly. g Some of these auto conversion folks have got "religion". They are 'true believers" and are as brainwashed as they come. Nothing concerning the laws of physics need apply. Fer instance..... 8.8 gph suggests 105 horsepower. 12 gph suggests 145 horsepower. How does one go 5 mph faster on 40 less horsepower and likely with a heavier engine? Dunno. but if you are a 'TRUE BELIEVER', nothing is impossible. If anything they said added up... someone, somewhere would get one of these 'WONDER' conversions certified and in the process make such folks very, very wealthy. It's not even close to happening. The certification process is something that keeps these black magic artists in the shadows of reality... on web sites and newsgroups.... beckoning the next rube, guppy, wannabee or whatever. No question, there is a sucker born every minute. Just ain't ever gonna me.. or you, from what I have observed. Barnyard BOb -- if it sounds too good to be true, it is. Are you assuming that a carburated, air cooled engine with a fixed advance magneto ignition has the same fuel efficiancy as a water cooled engine with electronic fuel injection and ignition? It's quite possible that the doctor was talking in imperial gallons as thats what we used to use in Canada before being saved by the metric system. I don't think there's a big enough market for engines to justify the expense of certification. I believe Toyota certified an auto engine conversion and then shelved the project because of the small numbers of engines they could hope to sell. Thielert has a certified Mercedes deisel auto conversion that they're selling now. Drew |
#5
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On Wed, 05 Nov 2003 01:39:14 +0000, Drew Dalgleish wrote:
of engines they could hope to sell. Thielert has a certified Mercedes deisel auto conversion that they're selling now. Not to us though. For Diesel the best shot may be the DeltaHawk: http://www.deltahawkengines.com/ - Holger |
#6
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Drew Dalgleish wrote:
: Are you assuming that a carburated, air cooled engine with a fixed : advance magneto ignition has the same fuel efficiancy as a water : cooled engine with electronic fuel injection and ignition? Actually, for an airplane application, even a carb'd gasoline engine can obtain very good fuel economy, since it can be manually leaned for its constant operation. The benefits of a more modern engine you describe a 1. Fuel-injected: Aside from poorer fuel/air distribution in a carb'd engine, fuel injection doesn't buy you much in an airplane. Even with computer-controlled injection, all that'll give you is better transient performance. At cruise (where most fuel is burned), computer-control doesn't buy you anything more than the red knob does. 2. Water-cooling: This is a double-edged issue that's a bit loaded. Everything else being equal, a water-cooled engine doesn't give you anymore power than an air-cooled engine. What it does buy you is the ability to run higher compression ratios and/or lower octane fuel (much lower CHTs). A higher CR will give you more thermodynamic efficiency. Also, a water-cooled engine allows for more flexible (read: efficient) cooling, but then again that's not a BSFC engine argument so much as an airframe issue. 3. Timing: Having adaptive timing doesn't buy you much in cruise, since that's where the fixed-timing is set to be optimal. It will allow you to possibly run lower octane fuel, but again that doesn't directly affect BSFC. While I agree with the idea that having liquid-cooled, fuel-injected (*perhaps* digitally controlled) high-compression gasoline engines are good from an aircraft *system* performance, they do not inherently increase an airplane engine's already excellent cruise fuel economy. I routinely get 0.42 lbs/hp*hr from my carb'd Lycoming O-360. -Cory -- ************************************************** *********************** * The prime directive of Linux: * * - learn what you don't know, * * - teach what you do. * * (Just my 20 USm$) * ************************************************** *********************** |
#7
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![]() : Are you assuming that a carburated, air cooled engine with a fixed : advance magneto ignition has the same fuel efficiancy as a water : cooled engine with electronic fuel injection and ignition? Actually, for an airplane application, even a carb'd gasoline engine can obtain very good fuel economy, since it can be manually leaned for its constant operation. The benefits of a more modern engine you describe a 1. Fuel-injected: Aside from poorer fuel/air distribution in a carb'd engine, fuel injection doesn't buy you much in an airplane. Even with computer-controlled injection, all that'll give you is better transient performance. At cruise (where most fuel is burned), computer-control doesn't buy you anything more than the red knob does. 2. Water-cooling: This is a double-edged issue that's a bit loaded. Everything else being equal, a water-cooled engine doesn't give you anymore power than an air-cooled engine. What it does buy you is the ability to run higher compression ratios and/or lower octane fuel (much lower CHTs). A higher CR will give you more thermodynamic efficiency. Also, a water-cooled engine allows for more flexible (read: efficient) cooling, but then again that's not a BSFC engine argument so much as an airframe issue. 3. Timing: Having adaptive timing doesn't buy you much in cruise, since that's where the fixed-timing is set to be optimal. It will allow you to possibly run lower octane fuel, but again that doesn't directly affect BSFC. While I agree with the idea that having liquid-cooled, fuel-injected (*perhaps* digitally controlled) high-compression gasoline engines are good from an aircraft *system* performance, they do not inherently increase an airplane engine's already excellent cruise fuel economy. I routinely get 0.42 lbs/hp*hr from my carb'd Lycoming O-360. -Cory ++++++++++++++++++++++++++++++++++++++++++++++++++ BINGO. Thanx, Cory Barnyard BOb -- over 50 years of successful flight |
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