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Old 12-16-2008, 10:00 PM   #1
jmlaser
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Default interesting head concept,... NO VALVES

Check these guys out
Coates

I am in now way associated with these people btw. Just found this and thought it to be interesting

discussion>?
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Old 12-16-2008, 10:34 PM   #2
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This has been around for a long time. It's a great concept.... as long as you can get everything to seal. I'm not sure if Coates is producing anything at the moment, but the last I heard there were some issues with lubrication and having to use exotic metals to get it hold up.
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Old 12-16-2008, 11:22 PM   #3
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It seems they use cylinder pressure to seal the valves. I could see extremely high loads and surface scarring being biggie right off the bat.
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Old 12-17-2008, 12:09 AM   #4
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I read an article on these heads a while back in a super chevy magazine. I think they cost somthing in the $10,000 dollar range. They only build the heads for engines with in line valves like a small block chevy. I don't think they even get any oil flow to the top end, the valve/cam shafts are sealed with some kind of ceramic seals. You get rid of all the valvtrain and you're supossed to get some outrageous power gains. The moment the spherical valves open they have maximum flow and the duration is a lot longer than with any cam lobe.
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Old 12-17-2008, 12:30 AM   #5
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Valve inertia is no longer an issue, so your "lobe lift rate" can be defined by the angular speed of the cam alone, without regard to the ramifications of trying to change a poppet vlave's direction at the same rate.
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Old 12-17-2008, 12:41 AM   #6
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pay to play, i guess.
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Old 12-17-2008, 12:44 AM   #7
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There is a catch, my guess is cost/durability, otherwise these things would be sweeping the ICE industry.
On another neat note, I suppose the lack of valves would also leave you a ton of freedom in respect to combustion chamber layout.
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Old 12-18-2008, 02:48 PM   #8
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I think this technology will make it especially in industrial and racing applications first.

I checked them out. They have a motorcycle co. and are building ind. stationary motors already. The stock price has gone from a .11 to a .58 high the past 12 months and it will probably swing some more, if it goes down again it will probably be a good place to put some of your kids college money. I would check it out, it looks better to me than gm right now.

Last edited by charliew; 12-18-2008 at 03:49 PM.
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Old 12-18-2008, 08:44 PM   #9
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Now giving stock advice based on an experimental engine technology might be a bit of a stretch.

the tech is old. 15+ years as far as I know. At this point if it is was currently viable, an OEM or major race team would have picked it up. Or a sanctioning body would have expressly forbidden them.

I don't mean to sound negative here, but my money would be on this company staying as a niche market.

I'm just going to say this one more time. Please don't invest your kids college money in this.
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Old 12-19-2008, 12:04 AM   #10
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Quote:
Originally Posted by strong_auto_concepts View Post
Now giving stock advice based on an experimental engine technology might be a bit of a stretch.

the tech is old. 15+ years as far as I know. At this point if it is was currently viable, an OEM or major race team would have picked it up. Or a sanctioning body would have expressly forbidden them.

I don't mean to sound negative here, but my money would be on this company staying as a niche market.

I'm just going to say this one more time. Please don't invest your kids college money in this.
Coates stock has been in the dumper for a long time.

IIRC my father in law has 5k shares. That he bought at $2.00 a share. Guess what its worth now.

I think coates main problem is cooling of the heads and that he wont run coolant thru them or something to that effect.
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Old 12-19-2008, 02:00 AM   #11
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Originally Posted by strong_auto_concepts View Post
Now giving stock advice based on an experimental engine technology might be a bit of a stretch.

the tech is old. 15+ years as far as I know. At this point if it is was currently viable, an OEM or major race team would have picked it up. Or a sanctioning body would have expressly forbidden them.

I don't mean to sound negative here, but my money would be on this company staying as a niche market.

I'm just going to say this one more time. Please don't invest your kids college money in this.
No kidding! This technology, even if it works, was created by a guy who has ZERO understanding of fluid mechanics and engine tuning. Look at some of the quotes I've pulled off his website:

http://www.coatesengine.com/technology-document.html
Quote:
Air traveling in through the venturi and into the cylinders of a combustion engine that is normally aspirated, travels in at a constant speed between 450 to 500 ft. per second and does not exceed this speed regardless of the RPM’s or throttle position. This is subject to the variation in barometric pressure and will only exceed this speed if a turbo charger or blower is incorporated.
^^^That just shows a complete lack of understanding regarding fluid flow. Not only does the air NOT travel at a constant speed (not even CLOSE), but turbocharging, or supercharging, does NOTHING to increase the speed; it increases the density only.

Quote:
If the volumetric efficiency of a normally aspirated engine exceeds 100% VE the results are in error.
^^^Again ... showing complete lack of knowledge regarding engine tuning and fluid flows. Almost ALL race engines go over 100% VE at some point in their power band, and many tuned street cars do as well.

Quote:
...no engine oil is present in the head of the C.S.R.V. Engine. This means the engine oil does not see the hottest parts of the engine, which was the exhaust Poppet Valves. These extremely hot components usually are engine oil spray cooled. This heat would breakdown the atomic structure of the engine oil, thus lowering the oil viscosity, therefore, oil changes are recommended every 3,000 to 5,000 miles. On the other hand, with the (C.S.R.V) incorporated in the engine design. Oil change intervals are extended to approximately 50,000 miles or more.


...The lubrication of the rotary valve assembly is accomplished by bronze shaft bearings.
50,000 miles or more? Yeah right. The cylinder head is NOT the main source of oil breakdown, and what about normal cylinder blow-by? Then you're going to "lubricate" these spherical valves, which endure full force of combustion, with no oil and just some bronze shaft bearings?! Holy f*** this guy is a TOOL.

Quote:
Hot exhaust valves in the conventional valve train system create "hot spots" which are the primary cause of pre-ignotion unless lead additives are present.
Lead additives had NOTHING to do with preventing pre-ignition. (lol @ "ignotion") What the heck is wrong with this idiot?!

Quote:
Reduced Lubrication Requirements - The use of seals and shaft bearing make oil lubrication of the valve heads unnecessary and lower the overall oil requirements of the Coates engine in comparison to a conventional engine. Without the component wear that characterizes typical poppet valve systems, engines using the spherical rotary valve design also produce fewer metallic particulates. As a result of these factors, the spherical rotary valve engine can realize longer maintenance intervals than conventional engines.
This just makes me want to punch someone in the face. This is SO BLATANTLY STUPID that it's almost beyond belief. AJKLSADJISAODKLDNASKLDASNJKLASNKAXUIRNEL!!!!!!

Just to show that this idiot can be even more idiotic:

Quote:
INTERNAL COMBUSTION
The nucleus of the atom is held together by an electromagnetic force. ((WRONG- it's the Strong Force)) The electrons rotate around the nucleus at the speed of light ((WRONG- only mass-less particles can go the speed of light)), and are negatively charged.

When the fuel and air mixture of elements are compressed and forced together in a combined sealed space. As the pressure and heat reaches its detonation point the trillions of electrons jump from one nucleus to another ((WRONG- electrons are not part of the nucleus)), this is called a (quantum leap) ((WRONG- it's called ionization)). This also happens at the speed of light((WRONG- these particles have mass)), creating tremendous force; one of the by products is heat. Heat is a ray of tiny excited atoms that penetrate all other elements at various rates((LOL!! VERY WRONG- how stupid do you have to be to think heat is "a ray of tiny excited atoms that penetrate all other elements"??! )). It is invisible and cannot be seen under a microscope, but in a desert heat rays may be seen in the distance ((WRONG- you can only see the effects of heat on light moving through the air)). Heat rays can be felt by just holding a hand close to a candle or fire. Fire is external combustion, so is any other explosion that is not sealed in a chamber. ((WRONG: detonation and deflagration are NOT the same thing ... example: C4 plastic explosive doesn't need to be confined to blow-up, and confined engine combustion is a flame despite confinement))
All that I've quoted isn't even the HALF of this person's idiocy. Just read the whole page and see if you can make it all the way to the end without wanting to punch this person in the head.

This guy EXEMPLIFIES the reasons I think degrees are overrated. How does someone like this get ANY sort of degree, let alone FUNDING?! UGH!!!

-Adrian

p.s. Just for fun, this might be the funniest thing anyone has ever written in total seriousness:

Quote:
HEAT RAYS

There are many types of rays:

* Light Rays
* Ultraviolet Rays
* Infrared Rays
* Microwave Rays
* Laser Rays
* Radioactive Rays
* Solar Rays
* Sun Rays
* Radio Wave Rays
* Xrays

There are many more.

The most powerful constant force on earth and in the universe is gravity. You cannot see it, but we can feel its pull.
That might be the single most inane thing I've ever read ... just wow.
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Old 12-19-2008, 02:16 AM   #12
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I think it is a better investment than gm or chrysler. I am sure it is a good solution to the antique valve train of the pushrod motor even with the ls1 motors. How many times were the rotary motors badmouthed. This looks like a great valve for a two cycle motor. The problem they will have is the ability to continue r&d with the economy on the way down for most of next year. This is way past the experimental stage as they are making and selling stationary motors and motorcycles. This technology can be applied to any inline valve motor very easily compared to making a completely new motor. This valve design and total seal rings might make the greenest gas motor yet. 50,000 miles on an oil change is believeable to me if the chamber is filled more precisely and the overlap is zero. A stationary motor that makes enough power at 2000 rpm runs much cooler and cleaner than a vehicle motor that needs varying rpms.
Only time will tell. .58 a share is pretty cheap. It's been as low as .11

Last edited by charliew; 12-19-2008 at 02:34 AM.
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Old 12-19-2008, 04:50 AM   #13
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Originally Posted by charliew View Post
I think it is a better investment than gm or chrysler. I am sure it is a good solution to the antique valve train of the pushrod motor even with the ls1 motors. How many times were the rotary motors badmouthed. This looks like a great valve for a two cycle motor. The problem they will have is the ability to continue r&d with the economy on the way down for most of next year. This is way past the experimental stage as they are making and selling stationary motors and motorcycles. This technology can be applied to any inline valve motor very easily compared to making a completely new motor. This valve design and total seal rings might make the greenest gas motor yet. 50,000 miles on an oil change is believeable to me if the chamber is filled more precisely and the overlap is zero. A stationary motor that makes enough power at 2000 rpm runs much cooler and cleaner than a vehicle motor that needs varying rpms.
Only time will tell. .58 a share is pretty cheap. It's been as low as .11
Anything is a better investment than GM or Chrysler right now.

But maybe I can make this simpler: those rotary valves will have to hold back THOUSANDS of psi in pressure during combustion. Since they have more than one square inch each, thats thousands of POUNDS pushing against each individual valve.

Now do you really see un-lubricated bronze metal-on-metal bearings making LESS metallic dust, having LESS friction, and lasting a long time with brief hits of 10,000+ pounds of force?

See, those valves are a great idea for gas pumps. Very simple, the biggest problem is the force and heat of combustion, which is not a problem in a simple gas pump. And nevermind that, even with total seal rings, piston blow-by is the largest detriment to oil contamination by far.

I have a hard enough time coming up with wild excuses that *might* make that engine last more than a few minutes. With how little that guy understands about physics, and engineering, you'd be better off betting on the lottery than betting on him making it work.

-Adrian
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Old 12-19-2008, 05:33 AM   #14
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He may be an idiot but it seems like it could be the start of something promising. Who knows, maybe someone with a little more know how and common sense can come along and perfect his setup.
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Old 12-19-2008, 07:59 AM   #15
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He may be an idiot but it seems like it could be the start of something promising. Who knows, maybe someone with a little more know how and common sense can come along and perfect his setup.
The idea of rotary valves has been around for a looooong time. Lubrication and sealing have always been the biggest problems. Because he has some running models does not mean it really works as a successful, reliable, engine. You can make a "jet engine" with a turbocharger and a flame tube, and you could use the thrust to push a really small object. But you couldn't fly with it.

That concept just isn't the ideal rotary valve, frankly. The trouble is that the surface which slides against the seal is the same surface which is exposed to combustion pressures. The way metal erodes, or even ceramic (though slower), means that it will stop sealing well very early on if the engine is actually run for enough full-power-hours.

A best-case-scenario would have them lasting a tenth as long as the apex seals to a Wankel Rotary ... and those seals aren't nearly as complex in terms of shape: they simply sit at the corner of a larger shape. The seals on this engine have to precisely match the shape of those "spherical" valves, or they will leak. Again, rotary valves may eventually have a good application, but this can't be it.

The other problem I have is lack of actual data. He says it runs a 14:1 compression ratio, but that's not the dynamic compression, which they do not disclose. It's said to be more efficient than a poppet valve engine, but where are the brake thermal efficiency maps? Where are the dyno-sheets? The engine is supposedly tested on a dyno ... so where's the data?

Doesn't it bother any of you that this guy hasn't even taken a highschool physics course, I mean I just can't like someone who claims to be "revolutionizing" ANYTHING when they think "silicone" is an element, that electrons travel at the speed of light, and that the heat from combustion is transmitted via "heat rays that are tiny excited atoms that penetrate all other elements".

All the "independant testers" were people who had degrees IN OTHER FIELDS OF RESEARCH. He was "cherry picking" for good reviews. Then, when interviewed, he just keeps repeating the same things without facts, measurements, or data of any kind. This sort of pseudoscience just bothers me.

*sigh* I just hate the way people seem to fall for the BS. Just use some big words most people don't understand (make sure you don't understand them either), mix them with some simple words that sound related which everyone can understand, but don't actually explain anything, then let bake in the minds of all the people who want to "jump on the band-wagon" any time a new, complex, idea comes out. They want to appear smarter than they really are by "understanding" this new idea before it's widely accepted. Just happens too often for my taste ... I like my science!

-Adrian
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Old 12-19-2008, 08:00 AM   #16
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Quite interesting concept but why not simply cool and lubricate the head?

Otherwise I fully agree with some of the criticism mentioned above.
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Old 12-19-2008, 03:11 PM   #17
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Adrian your critique sounds pretty logical. But if you look at the picture that comes up of 1/2 of a head you don't see a bronze bushing. You see a ballbearing and about a 1.0 shaft the valves are mounted on. I agree the valves appear to have a 1.0 inch square area that appears to be exposed in the combustion chamber. If the application is a stationary engine that runs 2500 rpms then the valve shaft would only be turning 1250 rpms. A sealed ball bearing will turn 1250 rpms all day long.

It seems to me the long internal combustion write up is a ploy to get idea stealers astray. The finished products that are shown seem to be well made to me. He says he started with this idea in 1961. Thats a pretty long developement cycle. I will bet there are plenty of people around to finish this idea and make it work if it doesn't already. The motors may have different pistons that utilize oil squirters and the combustion chamber may be in the liquid cooled cylinderwall for all we know.

I wonder if the patent rights and the economy have kept the big three from jumping on it. Coates claims it will be in europe first.

To me because of the efficiency possibilities this might make gas powered cars last a little longer in our culture.

I looked at the sec filings and he has one investor thats in big time.

Well to Wire Energy must not think there's too much smoke as they signed a 50 mil. liscensing agreement and also are buying a bunch of pumpmotors from Coates.

Coates got a 10 mil. loan in 2007 which was done in company stock. I can't find any stock market stuff that goes back past jan 07. The stuff I saw showed only a little over a dollar as the high.

Last edited by charliew; 12-19-2008 at 03:45 PM.
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Old 12-20-2008, 08:47 PM   #18
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Originally Posted by charliew View Post
Adrian your critique sounds pretty logical. But if you look at the picture that comes up of 1/2 of a head you don't see a bronze bushing. You see a ballbearing and about a 1.0 shaft the valves are mounted on. I agree the valves appear to have a 1.0 inch square area that appears to be exposed in the combustion chamber. If the application is a stationary engine that runs 2500 rpms then the valve shaft would only be turning 1250 rpms. A sealed ball bearing will turn 1250 rpms all day long.
I noticed that inconsistency. The design must have been changed after that was written.

In any case, the seal at the port itself is concerning: it's a "sliding" seal, and good seals at high temperatures rarely, if every, slide well.

Remember that various types of rotary valves have been tried on piston engines for a long time with little, if any, success. I wouldn't get my hopes up about this system, especially after reading what that guy has to say, and hearing the interviews.
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Old 12-20-2008, 10:10 PM   #19
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Originally Posted by SaabTuner View Post
I noticed that inconsistency. The design must have been changed after that was written.

In any case, the seal at the port itself is concerning: it's a "sliding" seal, and good seals at high temperatures rarely, if every, slide well.

Remember that various types of rotary valves have been tried on piston engines for a long time with little, if any, success. I wouldn't get my hopes up about this system, especially after reading what that guy has to say, and hearing the interviews.
Exactly what I've been trying to say. This has been tried, and tried again. There's a reason it's not popular, or successful, and that's probably not going to change.
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Old 12-21-2008, 02:12 AM   #20
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Originally Posted by kappathirteen View Post
He may be an idiot but it seems like it could be the start of something promising. Who knows, maybe someone with a little more know how and common sense can come along and perfect his setup.
Just to add to this thread what little I know:

1) Coates has been advertising their SRV design for at least 5 years or so since I found them. Their website has not changed much, if at all, during that time.

2) They have some pics on their site about car engine heads, but apparently aren't making or providing them to anyone. That's another big red flag.

3) At one point in past years, they claimed they were going to make aftermarket heads for Harleys. I have seen no progress, updates, nor anything else on this in at least 2 years.

4) The reason they don't lubricate the head is because this system makes wet lubrication unnecessary (if it actually works). The rotary valves spin in bearings, and have no other loads to speak of. This does make engine lubrication simpler.

Honestly given that they have not demonstrated any functional heads or support for any major manufacturer, something must be wrong with their technology. That's the most likely explanation I can think of.
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Old 12-21-2008, 10:21 PM   #21
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meh...............mazda has been using valveless motors for years. heck they even won the 24hrs of LeMans with a valveless motor.
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Old 12-22-2008, 06:12 AM   #22
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meh...............mazda has been using valveless motors for years. heck they even won the 24hrs of LeMans with a valveless motor.
And that motor has always had some sealing issues DESPITE the seals being partly lubricated by oil.

Putting a seal in the kind of focused, high temperature, high intensity, high flow, environment a piston exhaust valve sees, then expecting that seal to both slide, and adhere, to a steel alloy rotary valve, to seal with it ... is unrealistic at best.
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Old 12-22-2008, 09:40 AM   #23
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A lot of high alloy steels tend to gall when sliding past each other. If this thing is unlubricated, there is no way in hades that it will work.
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Old 12-22-2008, 05:32 PM   #24
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There was an article in Race Car Engineering magazine about why valves are still used in race cars. (Nov 08). It discussed various alternatives to valves. I didn't read the entire article so I don't have the details.
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Old 12-22-2008, 10:52 PM   #25
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Originally Posted by SaabTuner View Post
And that motor has always had some sealing issues DESPITE the seals being partly lubricated by oil.

Putting a seal in the kind of focused, high temperature, high intensity, high flow, environment a piston exhaust valve sees, then expecting that seal to both slide, and adhere, to a steel alloy rotary valve, to seal with it ... is unrealistic at best.
of course we are talking about motors with 3 moving parts. what's it take to rebuild one? i rebuild my rx7 every 30k, if it needs it or not.
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