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Old 08-06-2009, 12:57 PM   #31
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Quote:
Originally Posted by Spanrz
That "MPGe" figure is there because the car runs on ethanol, so the extra "e" on the end signifies the energy equivalent to a gallon of regular gasoline.
So 100 MPGe = a reality of 80 MPG of normal fuel.

And this is bad???

I mean sure it's not the 100 but 80 is still a hell of a lot better than what's out there at the moment.

Even at a decent 10l/100km you're talking about roughly 40ml/gal so then 80ml back to km is around 5l/100km on par with most of the current Direct Injection Diesel engines out on the market at the moment.

Hey Dan I'm not arguing with you about where the Ethanol comes from but what by product of corn is used, the sugar beet and cane is the pulp but what pulp from corn and wheat (just asking)?? The flip side of that is that the cane growers/ethanol producers in particular are getting subsidised to produce Ethanol, so essentially we still pay the difference in the end.

As for tolerances, not sure but I would have thought that the tighter an engine runs the more efficient, I mean F1 engines are all hand built so as to be able to run minimum tolerances. Sure they get rebuilt quite regularly but that could also be because they rev at around 12-15,000rpm.

There are other technologies that could be used and if this guy is an electrical engineer then there is one other way that I can think of that I actually put to an engineer many years ago to which he said it could work. Essentially it's a wasted fuel burn off set up but rather than just burning off remaining fuel in the cylinder you would actually fire two cylinders simultaneously. This would work best in a V8 as it essentially runs the engine as a twin bank 4 cylinder engine, but because you fire two cylinders at once you'd need less fuel in each, in theory half as a minimum but with proper tuning and timing you would use up to half that again. So you would have roughly a 50% fuel saving but with little to no drop in torque which is where the real power is due to the simultaneous firing of 2 cylinders this would make up for any losses in a single cylinder fire system.

Think about it, it would work.



just to add: I think the Revenge article pretty much tells the story, the big boys look at everyone as a crackpot first, expecting them to do their own R+D then look at it again if it actually works. Revenge have essentially bought into the rights so that when they show it does work and the demand from the consumer is there they have a big stake in the rights buy out when the big boys want in. On the upside they have a great economical engine that they can plonk into their own production model that saves fuel and gives you outstanding peformance at the same time, plus the US Government is giving huge subsidies to companies researching and promoting "Green Tech", so they are making money from all sides. Smart people.

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Old 08-06-2009, 02:03 PM   #32
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Quote:
Originally Posted by XRQTR
This would work best in a V8 as it essentially runs the engine as a twin bank 4 cylinder engine, but because you fire two cylinders at once you'd need less fuel in each, in theory half as a minimum but with proper tuning and timing you would use up to half that again. So you would have roughly a 50% fuel saving but with little to no drop in torque which is where the real power is due to the simultaneous firing of 2 cylinders this would make up for any losses in a single cylinder fire system.

Think about it, it would work.
Yes it can work, but......
Running less fuel in each cylinder is running the engine lean isn't?
Lean running engines create more heat, more heat, the greater chance to burn out a valve, incepting greater running costs and reduced realiability.
As Doug claims of "creating more thermal energy", this might be right.
But in the name of reliabilty? Come on.
But running lean, won't give you the power or torque as Doug claims.
As well with the extra NOx emissions it creates, he didn't mention that.

The concept of Learn Burn has been around for ages, but has dwindled off.
I wonder why.
http://en.wikipedia.org/wiki/Lean_burn

I've seen what engines do from running lean (on LPG/NG), burnt valves happen a lot and a costly repair.

This E85 concept is a great thing, the problem with people (business people), that market and solicit goods, with no backed up hardcore evidence of their claims is prone for critisim in my books.
(Just like Telstra saying we care for a Telecommunications industry, when all they do is wrap open copper cables in water laden pits with plastic bags to keep the water out.)

Now below is what I call, coming up with the goods and marketing it in the right way.
http://www.youtube.com/watch?v=a2JkMCzjTVE

Now if Doug had this plan, He would "Own".
But there is no base to his claims. Ok, his secret is solid then, but if you are not open about (to a certain degree), to me all you are doing is stalling.
Stalling = No base to claims.

The only base that he has is that he is building an engine plant, that went "Open" this month.
We will have to wait and see what becomes of it.

http://autoxprize.typepad.com/
All I can say, is that an Inventor that applies to run in a National Competition, touts that he has the goods for months, then all of a sudden his application is null and void, and does not fight his rights to stay in the competiton, has no base of his claims in my book.

For the Skeptics :
http://ecomodder.com/blog/amazing-11...cattle-manure/
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Old 08-06-2009, 03:59 PM   #33
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This whole thing reminds me of an infomercial they run in the USA all the time.

http://www.youtube.com/watch?v=vQAln...e=channel_page

Sorry, this is a bit of a butchered link to the ad, only because I couldn't find the original.
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Old 08-06-2009, 04:10 PM   #34
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Originally Posted by ltd
This whole thing reminds me of an infomercial they run in the USA all the time.

http://www.youtube.com/watch?v=vQAln...e=channel_page

Sorry, this is a bit of a butchered link to the ad, only because I couldn't find the original.
Hahaha ROFL.... I think this guy was in the ad (on the street)
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Old 08-06-2009, 05:35 PM   #35
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Quote:
Originally Posted by Spanrz
Yes it can work, but......
Running less fuel in each cylinder is running the engine lean isn't?

Are you sure about that??

By firing both banks simutaneously you effectively only need half the power from each bank, so think again whether you're actually running it lean or perhaps, just maybe rich.

To make 400hp you would only need to make 200hp on each side as they work in unison to make a combined power figure of 400hp, you're still thinking about making 400hp but forgetting that it takes less effort to make that per cylinder.
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Old 08-06-2009, 06:42 PM   #36
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Mate, your theory is a joke and simply doesnt make sense.

You would be trying to rotate 2 cylinders with half the fuel, you are not going to get the same power as 2 individual cylinders. Its pysically not possible.
You have to propel double the weight, double the friction with half the fuel, its simply going to produce much less than half the power.
There is no hidden power gains in a conventional combustion engine.

Using your theory you could have 100 cylinders firing at the same time with 100th of the fuel and youd expect the same amount of power as 100 individual cylinders and the appropriate amount of fuel? :
It wouldnt even move, the friction and the weight would be too great to be impacted by 100th of the fuel (explosion).
You really need to go back to school and take basic physics
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Old 08-06-2009, 06:58 PM   #37
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Also if you only putting half the fuel into a conventional cylinder, it simply wouldnt combust properly, they are designed specifically for the appropriate amount of air/fuel mix. Are you forgetting petrol needs a specific mix with air, to actually explode? You reduce that by half you simply wont get an explosion.
You reduce the fuel by half, you are going to have to reduce the cylinder by half, which gives you half an engine, half the power....
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Old 08-06-2009, 07:42 PM   #38
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Come on, this crap has been well-and-truly debunked a long time ago.

Some reading: http://www.corner-carvers.com/forums...ad.php?t=38411
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Old 08-06-2009, 08:03 PM   #39
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Hee... Hee.. told ya he was a CRACKPOT!!!!!... Pot(SMOKER)tery
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Old 08-06-2009, 08:13 PM   #40
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Quote:
Originally Posted by XR6 Martin
Mate, your theory is a joke and simply doesnt make sense.

You would be trying to rotate 2 cylinders with half the fuel, you are not going to get the same power as 2 individual cylinders. Its pysically not possible.
You have to propel double the weight, double the friction with half the fuel, its simply going to produce much less than half the power.

Really??

I didn't realise that once you fire two cylinders you suddenly double the rotating mass of a single engine :togo:

As for making sense I've put the idea to engineers who have all said it would work, and you do what exactly??
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Old 08-06-2009, 09:47 PM   #41
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Quote:
Originally Posted by XRQTR
Really??

I didn't realise that once you fire two cylinders you suddenly double the rotating mass of a single engine :togo:

As for making sense I've put the idea to engineers who have all said it would work, and you do what exactly??
Because you are only using half the fuel per cylinder, you are in effect making the energy produced from the combustion, push twice as much rotating mass and twice as much friction, as opposed to a conventional engine.

Yet you somehow think thats irrelevant?
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Old 08-06-2009, 11:25 PM   #42
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I like this piece from that other site (www.corner-carvers.com)...

"And with four bolt wheels. I guess all that tech stuff used up his brake budget. "

Wouldn't u feel happier with at least five bolts on each wheels with 400hp under the hood?
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Old 09-06-2009, 12:12 AM   #43
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Quote:
Originally Posted by XR6 Martin
Because you are only using half the fuel per cylinder, you are in effect making the energy produced from the combustion, push twice as much rotating mass and twice as much friction, as opposed to a conventional engine.

Yet you somehow think thats irrelevant?

You're firing two cylinders simultaneously, even if it is half the fuel "per cylinder" it's the same amount of fuel as firing just one cylinder, so again how are you doubling the mass??

If anything you would be lessening the mass by sharing the work load.
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Old 09-06-2009, 01:55 AM   #44
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Quote:
Originally Posted by XRQTR
You're firing two cylinders simultaneously, even if it is half the fuel "per cylinder" it's the same amount of fuel as firing just one cylinder,
I can see where you are coming from, but it's just not logical.

Your rule of thumb only works when you are working with the same amount of capacity (a very large 5.4L 4 CYL or a 5.4L V8).
True, you are using the same amount of fuel for the 2 cylinders vs the 1.
And the air displacement is the same.
As your working on the theory that 2 cylinder's (8cyl) light at the same time, you would have a very very lumpy V8 that would need a huge heavy flywheel to take the crank over to the next firing. Because there are only 4 powerstrokes, not 8.
If you've done some engine work, you'd understand why a 4cyl has a heavier flywheel than an 8cyl.
Heavier flywheel would give it some massive torque, but not so sure on the HP/KW base.

However, going on the 4 Vs 8 in reality, the capacity (Volume) of air would be different. If based on todays engine sizes. 4Cyl vs an 8Cyl.
Thus giving you a leaned mix for the 2 cylinders (on the 8) and the right ratio (stoich) for the 4Cyl, that is if you are using the "same" amount of fuel on the one cyl (4cyl) as to the 2cylinders (8cyl).

In any case of displacement, it has to carry the right mixture (stoich).
If it's not stoich, then it don't run as well or at all. You can have a range of ratios from 12 to 16, but that's under engine operating ideals.
http://books.google.com.au/books?id=...um=2#PPA322,M1

I do remember the Mythbusters having trouble a few times getting the mixture of fuel to air right, on a few of their episodes (Exploding house using bug bombs and the Cell Phone Destruction) I think are good cases.
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Old 09-06-2009, 02:26 AM   #45
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Quote:
Originally Posted by Ohio XB
I live in Ohio and just going from what I remember reading about this last year, it gets about 80 mpg on E-85 fuel, bottom line. That's great, if it is true.

The guy is an electrical engineer and he claims that is what enables him to achieve this; high tech electronics that he designed himself.

I am still awaiting for proof positive evidence; labratory confirmed fuel consumption and dyno figures. I'll have to look into this to get caught up on the progress since last year. It was in the local news then but hasn't been since then.



Steve


Ahh sounds like modern day Polariser talk!



80mpg, in what car? Sounds like it might have a 2 speed diff, maybe a 10 speed spicer behind it.
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Old 09-06-2009, 08:10 AM   #46
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Quote:
Originally Posted by XRQTR
You're firing two cylinders simultaneously, even if it is half the fuel "per cylinder" it's the same amount of fuel as firing just one cylinder, so again how are you doubling the mass??

If anything you would be lessening the mass by sharing the work load.
Lets say the rotating mass of one cylinder is 2kg, and two cylinders is 4kg.
Lets say the energy from a combustion in a converntional cylinder is 10000Kj.
So you would have 20000Kj of energy across those 2cylinders weighing 4kg.

Now you want to halve the energy produced per cylinder, so 5000kj per cylinder, but the mass of the rotating cylinders is staying the same, 4kg.
It doesnt matter if you fire the cylinders at the same time or not, the rotating cylinders still weigh the same, and the energy produced is still less.

Theres no trick to the fundamental laws of physics, as far as I know your scenerio still occurs of planet Earth and those laws still apply.
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Old 09-06-2009, 09:32 AM   #47
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XR6 MArtin is Spot on, but added to his point is that the two pistons sliding up and down in the cylinder are actually reciprocating masses, meaning that they have to not only overcome their weight, but the added pressure of compressing the air/fuel mix. If you apply Newtons first law of physics which is that force equals mass times acceleration or F=MA, then you find that say a 2kg piston at idle of about 750rpm in a cylinder which travels 10cm on the upstroke and 10cm on the downstroke; it works out that the piston is moving at 2.5m/s.

Now, apply this to the weight of 2kg which equals 20 newtons and you have 50 Newtons of force required to overcome just the weight of the reciprocating mass. Now, with 2 cylinders firing simultaneously you'd require 100N of force, and this is not taking into consideration the load from compression and the friction against the cylinder.

Now, lets say that X amount of fuel is sufficient to get one piston (50 Newtons) to do its thing. Halving that will produce 0.5X which in a perfect world will give you 1.25m/s of one piston; so half idle of 375rpm. Now, double the weight to 100 Newtons as you want two cylinders to fire simultaneously, so you have 0.25X as the fuel component trying to overcome the 100N of force required to move the reciprocating mass meaning that it will travel at 0.625m/s or idle at 187.5rpm.
As anyone will tell you, it would not be possible to idle any reciprocating engine small enough to fit into a car, especially considering the weakness of the power stroke. Further, that weak power stroke would not be able to overcome the other forces applied to the piston such as friction, compression, thermal efficiency and a host of other issues. Basically, what these guys are proposing is bogus.

As for leaning of fuel burn; do you may remember a case about 12 years ago of a commuter airplane crash in Whyalla SA?
In this case it was found that as pilots have leaning procedures of large capacity engines, the junior pilot in this case overleaned the two turbo charged 6 cylinder AVCO Lycoming engines to the point that the cylinders got so hot, he burnt holes in 3 of the pistons, burnt valves and melted the electrodes off the spark plugs (2 in each cylinder). Subsequently, both engines failed and he crashed killing all those aboard. No, I refer to my earlier post about EXTENZE as to the veracity of the claim made by an amateur website at best.
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Old 09-06-2009, 01:04 PM   #48
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F=ma is Newtons second law

a = acceleration, not velocity. Instantaneous acceleration for opposing pistons will be different because of the angular acceleration (rad/s²) is governed by rod inclination. So you can't apply a linear analogue of two times mass times average velocity.

more relevance would be application and summation of (dØ/dt)²cosØ, (dØ/dt)²sinØ, (d²Ø/dt²)cosØ , (d²Ø/dt²)sinØ variants, depending on centreline of the pins and various journals for all component forces in the train.
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Old 09-06-2009, 05:49 PM   #49
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F=ma is Newtons second law

a = acceleration, not velocity. Instantaneous acceleration for opposing pistons will be different because of the angular acceleration (rad/s²) is governed by rod inclination. So you can't apply a linear analogue of two times mass times average velocity.

more relevance would be application and summation of (dØ/dt)²cosØ, (dØ/dt)²sinØ, (d²Ø/dt²)cosØ , (d²Ø/dt²)sinØ variants, depending on centreline of the pins and various journals for all component forces in the train.
As for your first point I concede that it was indeed Newtons second law, but your assertion that it is velocity I disagree with entirely. Pistons are constantly changing direction and accelerate from one point to another. Something that changes direction constantly in the same plane is under constant acceleration through inertia; even at all positions in the stroke. It may seem infinitessimal the acceleration component but in a conventional ICE, the inertia of the moving piston is overcome by other forces acting on it throughout the cycle.

In my example I am referring to the claim that the PP made regarding the pistons simultaneously being at the same point in the cycle. He was talking about two cylinders firing at once on half the fuel so therefore my example was designed to be simplistic; ergo position of the crank and frictional forces so the COG of the reciprocating masses and other components in the drivetrain was left out. Again, the PP was talking of two cylinders firing at once on half the fuel; not sequential and therefore no reciprocal motion.

Inertia from other rotating mass components within the engine as well as various other components on the calculation I deliberately left out, as there frankly is far too much guess on the variables to sufficiently demonstrate that the original theory of a V8 firing 2 cylinders at once on half the fuel is anything other than ludicrous.
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Old 09-06-2009, 06:32 PM   #50
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Without getting into semantics, the piston does not travel at a constant speed, nor acceleration. You can visualise this simply by considering the speed TDC and BDC. The rod inclination tends an ever changing angle over the stroke. The acceleration figure is quite substantial in a typical car engine.


I also contend you can't substute velocity for acelleration in the formula. The "a" is acceleration and velocity is it's integral, just as displacement is the integral of velocity. Velocity and acceleration vectors are different tensors.

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Old 09-06-2009, 06:39 PM   #51
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Pass me the red cordial please....PB
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Old 09-06-2009, 06:46 PM   #52
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Pass me the red cordial please....PB

LOL

It quite easy stuff really, and I'm sure there's plenty of explanations on the web that put it in simpler terms with pretty graphics.
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Old 09-06-2009, 10:11 PM   #53
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Quote:
Originally Posted by XR6 Martin
Also if you only putting half the fuel into a conventional cylinder, it simply wouldnt combust properly, they are designed specifically for the appropriate amount of air/fuel mix. Are you forgetting petrol needs a specific mix with air, to actually explode? You reduce that by half you simply wont get an explosion.
You reduce the fuel by half, you are going to have to reduce the cylinder by half, which gives you half an engine, half the power....
actually the fuel burns very quickly, if it explodes then its detonating... :
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Old 10-06-2009, 09:48 AM   #54
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PISTON ACCELERATION
The force it takes to accelerate an object is proportional to the weight of the object times the acceleration. From that it is clear that piston acceleration is important because many of the significant forces exerted on the pistons, wristpins, connecting rods, crankshaft, bearings, and block are directly related to piston acceleration. Piston acceleration is also the main source of external vibration produced by an engine. (Torsional vibration is discussed separately on another page.)

Acceleration is, by definition, the first derivative of the velocity curve, or in other words, the slope of the velocity curve at any given point along the reference. More simply, it is a measure of how rapidly velocity is changing, usually expressed with reference to time. If velocity does not change with respect to the reference, there is no acceleration. Conversely, if velocity changes very rapidly with respect to the reference, there is a large acceleration. (See Velocity and Acceleration for a more thorough explanation.)

It is clear from Figure 7 that the piston velocity is constantly changing with respect to a constant value of crankshaft rotation. Therefore, In order to move from the zero-velocity point (TDC) to the maximum velocity point, the piston must be subjected to a large acceleration function which varies with the angular rotation of the crankshaft.

Figure 8 shows the acceleration, velocity and position plots for the example CCP under discussion. (All numeric values presented are for the R / S in this example.)



The maximum positive value of acceleration (100%) occurs at TDC. Between TDC and maximum piston velocitty (74° in this case), acceleration is positive but decreasing toward zero (the piston velocity is still increasing but less rapidly). At maximum piston velocity (74° at this R / S ), the piston stops speeding up and begins to slow down. At that point, the acceleration changes direction (from a "plus" number to a "minus" number), and in so doing, momentarily passes through zero.

Figure 8
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Old 10-06-2009, 10:50 AM   #55
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OK so now we are on the same track, lets investigate the issue of firing up two pots simultaneously as opposed to one:

On any engine, when the power stroke occurs it is not only applying force on the associated piston, it is applying force on all pistons via the crankshaft. So at any instant the mass of the all the pistons are being accelerated/decelerated. All will be experiencing different opposing forces due to valve position, side wall loading, compression, blowdown etc., but the piston mass will be be constant.

If indeed two pots were fired simultaneously the liberated energy would be roughly the same for the same power. It's questionable if there wouldn't be any AFR change, because, say with a V8, it would be like two four pot engines sharing a common crankshaft.

The core of the claims 100MPGe is that the current control of the engines is so poor there is an opportunity for a manifold increase in efficeincy, merely by precise calibration. Somewhere I think he mentions factory engines have an efficiency of figure of 10% or 15%? That simply is not true. Simple maths tells otherwise..e.g.

lets say petrol has a specfic energy value of 35mJ/litre and an average specfic weight of 0.72. At 30% engine efficiency that works out to ~70mg/kW or 0.096cc/kW at stoich. Check that against the actual fuel rates currently required and it's pretty close. In other words significant gains in the order of magnitude claimed, just don't stack up.
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Old 10-06-2009, 05:04 PM   #56
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Plus any engineer/scientist knows that the Otto cycle engine has a theoretical limit to its efficiency anyway, by nature of its design.
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