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Bigshu

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Yes yes....but they run usually 300 000 miles. So plenty or hours left. Spark plugs etc must be new to get the mileage right but still something to work on...and tunable from 117 hp to 650 hp....with new parts and tweaking.
Right, you plan to fly behind an engine that only makes the hp you mention at rpm above where most flight engines run. That means you need a reduction gear to get the prop rpm right. Those aren't common, you'll probably have to build your own, and that can run into many hundreds of dollars by itself. Tuning and tweaking will usually call for forged or billet racing parts. It just isn't as inexpensive as you think, or everyone would already be doing it. You can get crate LS engines for a reasonable price, but you still don't see them commonly on aircraft, because they still need custom reduction gearing to fly. Among other challenges, your modern computer-controlled engines will need all new control logic to manage spark timing and fuel flow. "Modern" as in anything made after the early 80s
 
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Urquiola

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Lots of threads on Chevy V8 conversions, not sure about that specific one.
Again, I suggest the article added elsewhere in this site:
'Power struggle: Why car engines won't fly', by Don Sherman, Smithsonian Air and Space Magazine, Jan 1997, pag 72 on.
'Man is the only animal who stumbles twice on the same stone' (Spanish proverb. Or not Spanish?)
Blessings +
 

Monty

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Again, I suggest the article added elsewhere in this site:
'Power struggle: Why car engines won't fly', by Don Sherman, Smithsonian Air and Space Magazine, Jan 1997, pag 72 on.
'Man is the only animal who stumbles twice on the same stone' (Spanish proverb. Or not Spanish?)
Blessings +
That article was nothing but a bunch of anecdotes, and has no basis in engineering argument. Automotive engines operate at higher rpm to achieve their output. The parts are sized accordingly. Coupled with a well designed gearbox they work just fine. The dyno testing modern auto engines endure is at 100% duty cycle and much worse than anything an aircraft engine could endure. I get really tired of seeing this article quoted. Aircraft engines do NOT operate at 100% duty cycle. If they are normally aspirated, and flown at altitude, they are well below 50%. What doesn't work is expecting to boost the output of an automotive engine by 50% and then do a terrible job designing the gearbox and other systems. This is the reason they have a poor record. Those who have done their homework have proven over and over automotive engines can work just fine. After all, they have a long track record in boats, which completely negates the entire argument about why they can't work in an airplane.
 

Malish

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Russia. City of Volgograd
Again, I suggest the article added elsewhere in this site:
'Power struggle: Why car engines won't fly', by Don Sherman, Smithsonian Air and Space Magazine, Jan 1997, pag 72 on.
'Man is the only animal who stumbles twice on the same stone' (Spanish proverb. Or not Spanish?)
Blessings +
Most automotive engines have RPM "red line" at 6500 RPM's. In aircraft use they could be set limit RPM's 4500-5000 for takeoff and 4000 for the cruise, then automotive engines will have TBO as same as aircraft piston engines. And more, automotive engines in aircraft will be more economical and much chipper to mountain or overhaul ;)
In today post in this tread guy said that it cost him 3 times less to operate his C-172 with automotive V-8, then regular C-172...
 
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Urquiola

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That article was nothing but a bunch of anecdotes, and has no basis in engineering argument. Automotive engines operate at higher rpm to achieve their output. The parts are sized accordingly. Coupled with a well designed gearbox they work just fine. The dyno testing modern auto engines endure is at 100% duty cycle and much worse than anything an aircraft engine could endure. I get really tired of seeing this article quoted. Aircraft engines do NOT operate at 100% duty cycle. If they are normally aspirated, and flown at altitude, they are well below 50%. What doesn't work is expecting to boost the output of an automotive engine by 50% and then do a terrible job designing the gearbox and other systems. This is the reason they have a poor record. Those who have done their homework have proven over and over automotive engines can work just fine. After all, they have a long track record in boats, which completely negates the entire argument about why they can't work in an airplane.
Automotive engines work most time at less than 20% of nominal top power, opposite to aircraft engine, rarely going below 50% to 60% of top power.
Some basic info exists in
'How much overall energy does the Automobile require?' SAE Journal Automotive Engineering, vol 80, n 7, pp 36-38, Jul 1972
'How much Energy is needed to produce an Automobile?' SAE Journal Automotive Engineering, vol 80, n 7, pp 39-40, Jul 1972
I won't use an automobile engine in my homebuilt airplane, I guess it are heavy, not reliable enough, not economical, besides a Wankel, but the line now could be an hybrid approach, a Wankel or Turbine powered generator, power sized a bit over cruise power needs, low weight, low cost fuel, with an small battery as 'buffer', for some higher power demanding situations: take off, climbing,...
Small turbines seem having a Reynolds number drawback, making impossible hacing a los SFC low power turbine.
But sports aviation is an sport, a hobby, not a bussiens where economy rules.
btw: Are you aware of comment by Henry Mignet, patriarch of sports aviation?
'Sport aviation being a lonely sport, no one should think in going sunday morning for a fly with his girlfriend'
Today, soprt airplanes allow flying wit your girlfriend, your kids, your pets,...
In front of a Bubble Car, a british car writer said: 'You'll be in trouble in case of parking near a wall, and other situations, to have your girlfriend out of car, but if you have this type of cheap car, you won't have a girlfriend'
I started thinking H Mignet was wrong after having a look at: 'The fabulous, furry, freak brothers', 'Country life', some girls went with them. A movie is about: 'Where the boys are', Henry Levin, 1960.
Blassings +
 

Monty

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Automotive engines work most time at less than 20% of nominal top power, opposite to aircraft engine, rarely going below 50% to 60% of top power.
Some basic info exists in
'How much overall energy does the Automobile require?' SAE Journal Automotive Engineering, vol 80, n 7, pp 36-38, Jul 1972
'How much Energy is needed to produce an Automobile?' SAE Journal Automotive Engineering, vol 80, n 7, pp 39-40, Jul 1972
I won't use an automobile engine in my homebuilt airplane, I guess it are heavy, not reliable enough, not economical, besides a Wankel, but the line now could be an hybrid approach, a Wankel or Turbine powered generator, power sized a bit over cruise power needs, low weight, low cost fuel, with an small battery as 'buffer', for some higher power demanding situations: take off, climbing,...
Small turbines seem having a Reynolds number drawback, making impossible hacing a los SFC low power turbine.
But sports aviation is an sport, a hobby, not a bussiens where economy rules.
btw: Are you aware of comment by Henry Mignet, patriarch of sports aviation?
'Sport aviation being a lonely sport, no one should think in going sunday morning for a fly with his girlfriend'
Today, soprt airplanes allow flying wit your girlfriend, your kids, your pets,...
In front of a Bubble Car, a british car writer said: 'You'll be in trouble in case of parking near a wall, and other situations, to have your girlfriend out of car, but if you have this type of cheap car, you won't have a girlfriend'
I started thinking H Mignet was wrong after having a look at: 'The fabulous, furry, freak brothers', 'Country life', some girls went with them. A movie is about: 'Where the boys are', Henry Levin, 1960.
Blassings +
I put my faith in hardware, not words. Go look at Ross' airplane plus many others successfully doing what you are saying can't be done.
 

PMD

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Martensville SK

Malish

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Messages
839
Location
Russia. City of Volgograd
Automotive engines work most time at less than 20% of nominal top power, opposite to aircraft engine, rarely going below 50% to 60% of top power.
Some basic info exists in
'How much overall energy does the Automobile require?' SAE Journal Automotive Engineering, vol 80, n 7, pp 36-38, Jul 1972
'How much Energy is needed to produce an Automobile?' SAE Journal Automotive Engineering, vol 80, n 7, pp 39-40, Jul 1972
I won't use an automobile engine in my homebuilt airplane, I guess it are heavy, not reliable enough, not economical,
This B-29 replica will use automotive 4 cyl. Honda engines and reason builder using them on this aircraft - he use same Honda engine on his Piper cub for 10 years now without any problems with it(yellow Piper cub on background) :)

116251-22f73dc3c65a6fe7687c4fdce409ba3f.jpg
 

Bigshu

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KCMO, midwestern USA
Just to put a little historical perspective to this discussion: The Ford V8-60 flathead was a fully certificated aviation engine.

I have seen the cast iron Ford produced on at Cole Palen's IIRC

Then there was the aluminum one: The Flying Ford Flathead… | The Jalopy Journal The Jalopy Journal

There was also a fully certified air cooled derivative: Church V-8 - Wikipedia

And, of course a lot of pietenpols used the inline 4
Seems like there are a few Piets with Corvair power too.
 

Urquiola

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Messages
316
Location
Madrid, Spain
This B-29 replica will use automotive 4 cyl. Honda engines and reason builder using them on this aircraft - he use same Honda engine on his Piper cub for 10 years now without any problems with it(yellow Piper cub on background) :)

View attachment 128915
As my grandmother Lola, tortured to death in a Madrid Army Hospital used saying: 'The better is enemy of the good', but this was not her sentence, it is in the Old Testament.
You have the freedom for this, if FAA or equivalent gives you the permission, but I won't fly with automobile avionized engines, besides Chevy Corvair; VW 'Käfer', (Ladybug); and Wankel.
But some 'Aircraft engines' were not at all good, you know the only Steam Engine Aircraft successful in flying, besides very early attempts, was the Besler steam machine installed in a Travel Air 2000, having as original engine a Curtiss OX-5, they say something flying with an OX-5 would fly with anything.

Steam engines, also Stirling engines, heavier than steam machines, are both external combustion engines that can burn anything, with nearly zero emissions, but its thermodynamic cycle is inherently less efficient than any ICE.
Image is of a model Stirling engine 'Smurf 88', offered in AliExpress.Motor Stirling Smurfs 88.jpg
Blessings +
 
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