Rotary valves rule, OK!

[SSbaby]

OHVs and DOHCs are yesteryear. This valve system freaked me out, man!

Coates SRV - V-8 Racing Engine


Coates Patented Rotary Valve System


CSRV 6-Cylinder Engine Head & Components


http://www.coatesengine.com

[svo347]

There was an article in Motor awhile ago, maybe 1 yr?..
Went through the workings of the Spherical valve system, also noted a couple of advantages & disadvantages...

[SSbaby]

Well, here's the positive spiel on the system...

In the late 1960s and 1970s, most vehicles combustion engines in the USA were running at a compression ratio of 12 to 1, which resulted in an engine efficiency of approximately 55 percent. The rest of the engine power was lost in friction, pumping and heat loss. When it was found that lead additives in fuel had an adverse effect on the environment, it was removed from the fuel. This caused the poppet valves and combustion chamber on poppet valve engines to overheat, raising the temperature to in excess of 2500 degrees F and damaging the poppet valves.

The answer to this problem was to lower the compression ratio of all engines to 10 to 1 or lower, thus reducing efficiency of the combustion engine to approximately 24 percent. This means less miles per gallon (MPG), lower brake horse power (BHP) and lower torque. The air traveling in through the inlet venturi of a combustion engine inlet travels at a speed of up to 450ft a second. In normally aspirated engines this works fine, but in poppet valve engines, the BHP and torque decreased as the air traveling in does not increase in speed unless a turbo or supercharger is incorporated. At higher RPMs the poppet valve tends to float or bounce and is unable to service the cylinder and chamber to capacity with air and fuel mixture. This is the reason for adding two extra valves to modern engines, causing unburned fuel to escape through the exhaust system which leads to a loss of power, lower MPG and produces significant pollution.

The poppet valves' stems are lubricated with engine oil which is burned off after a short period of running. The stem of the inlet valve system is also lubricated with engine oil, which is washed off and inducted into the combustion chamber with air and fuel mixture. This slows combustion and produces further emissions and eventually clogs the catalytic converter.

Variable valve timing has advantages at lower RPMs as it can shorten the overlap duration of the valves, but has extra moving parts that eventually wear. On quick deceleration, it can cause piston and valve contact where serious damage can occur. Poppet valves, if not activated with hydraulic systems, must have clearance readjusted periodically. The successful poppet valve of the original combustion engine has been used and modified continuously until the present. However, it is the most troublesome part of a combustion engine and has lower efficiency at higher RPMs.

Remedy
The Coates Spherical Rotary Valve Engine is the most advanced in the world, with the most positive valving system ever built. The breathing capabilities of the system are almost double that of a poppet valve. For instance: a static test of a five-litre poppet valve engine on an airflow machine produced a reading of 133 cubic feet per minute (CFM) with valve fully opened. The five-litre Coates Spherical Rotary Valve Engine on the same machine, however, produced a reading of 319 CFMs fully opened; a colossal advantage in airflow comparison. A five-litre poppet vavle engine tested on a dynomometer under the same loads and conditions at 5500 produced 480 BHP and 454 foot pounds of torque. The maximum RPMs on the poppet valve engine were 5700 RPMs; the Spherical Rotary Valve Engine in comparison reached 14,850 RPM's, The Coates Spherical Rotary Valve comprises two spherical rotary valves assembled on two separate shafts - one for inlet and one for exhaust. They rotate on ceramic carbon bearing with no oil lubrication, the spheres do not make contact with any part of the housing. The seals are a floating type and are also made of a ceramic material. They have two piston rings and are floating in a small cylinder-type chamber, they are activated by the compression and the combustion strokes of the engine which allows 100 percent sealing effectiveness, when compressed.

Because the valves rotate away from the combustion chamber and are vented and charged on the opposite side of each sphere, this creates a lower combustion chamber temperature, allowing for higher compression ratios to be used thus creating an extremely efficient engine. Some of the Coates Spherical Rotary Combustion Engines are at 12 to 1, 13 to 1, 14 to 1 and 15 to 1 compression ratios depending on the application.

© Automotive Asia Technology

Originally Posted by svo347

There was an article in Motor awhile ago, maybe 1 yr?..
Went through the workings of the Spherical valve system, also noted a couple of advantages & disadvantages...

Lubrication and wear would be the big disadvantages surely?


O

[SSbaby]

Originally Posted by O-one

Lubrication and wear would be the big disadvantages surely?


O

"They rotate on ceramic carbon bearing with no oil lubrication, the spheres do not make contact with any part of the housing. The seals are a floating type and are also made of a ceramic material."

[svo347]

Increased engine efficiency
adaptable to all fuel types
Reduced lubrication requirements
Lower manufacturing costs
Lower emmissions

[EFFalcon]

someone make one for eseries :P

[Steffo]

I posted about CSRV on the old Ford Forum. And yes, it makes OHV and DOHC look like a total waste of time.

Coates put his Spherical Rotary Valve setup on a stock Ford 302W that was producing 260hp 260ftlbs... and from that simple change, the engine was producing 450hp 450ftlbs, able to spin 14,750rpm, and was driven 275,000 miles (440,000km) on the street to prove its reliability. Bring on CSRV I say!

[Steffo]

Oops... didn't notice what I posed was already in the article on Post #3... :

[xdc351]

Yes, sure. I'll bet any windor could run to 14,000 RPM with just a head change. I mean, what would subjecting any stock (or 99.99% of aftermarket) pistons/con rods/cranks to speeds 2-3x higher than they were intended?

I'll give you a hint.... and it involves engine pieces normally found on the inside winding up on the road underneath.

The technology might be workable one day, but seriously, that is a load of crap.

[Pik0]

would it be that hard to change over for manafacturers eg Ford and Holden?

[Steffo]

Originally Posted by xdc351

Yes, sure. I'll bet any windor could run to 14,000 RPM with just a head change. I mean, what would subjecting any stock (or 99.99% of aftermarket) pistons/con rods/cranks to speeds 2-3x higher than they were intended?

I'll give you a hint.... and it involves engine pieces normally found on the inside winding up on the road underneath.

The technology might be workable one day, but seriously, that is a load of crap.

Its a load of crap eh? That's why Coates has fulfilled a $90m contact for an American trucking company to build them an all new 800ci Diesel engine. And they now have a $575m contract for a Motorcycle company to provide engines for them. I'm sure its all a load of crap... that's why they're winning customers....

[Perana]

Yes but explain how they got stock Wheezer rods/crank/piston to endure 15000rpm? It isnt possbile.....

[Steffo]

The CSRV setup doesn't use the factory piston. It eliminates the camshaft completley for a start.. its a completley new top end, and reduces the rotating parts in an engine by a great amount.

[XRQTOR]

Originally Posted by Steffo

Its a load of crap eh? That's why Coates has fulfilled a $90m contact for an American trucking company to build them an all new 800ci Diesel engine. And they now have a $575m contract for a Motorcycle company to provide engines for them. I'm sure its all a load of crap... that's why they're winning customers....

$575,ooo,ooo is small change esp for a new upcoming company such as this one.








This shit is pure gold, it gives me a fat just thinking about a GTHO that will rev to 14,ooorpm.

[XRQTOR]

Im willing to pull my Boss apart as a test car for these new heads. Who's going to donate them to me.

[Perana]

Pistons may have changed but that doesnt make the rods or crank any more durable... less top end friction would make a slight difference but nothing like 3 times the normal engine speed! its just not possible even as xdc351 said with 99.9% of aftermarket parts...

BTW im not doubting that there are some benifits of these heads..

[Sox]

Originally Posted by Steffo

The CSRV setup doesn't use the factory piston. It eliminates the camshaft completley for a start.. its a completley new top end, and reduces the rotating parts in an engine by a great amount.

You're missing the point Steffo, a 302 Wheezer is not likely to see 15000rpm, no matter what intake system is applied.

It has nothing to do with how reliable or efficient the intake system is, it's to do with piston speed, conrod strength, block strength, etc.

I'm not doubting the system, however the test seems ot be a little one sided if they compare a Wheezer which is only producing 260hp to there head which produces 450hp.
It's pretty common knowledge that a good 5L Wheezer can produce in excess of 500hp (and more) with the right combination.

So whilst there system looks good, it will take a more sensible comparison to prove the sceptics.

Rick.

[Raptor]

Originally Posted by SSbaby

OHVs and DOHCs are yesteryear.....

I suppose you think you've stumbled onto something new and revolutionary here SSbaby? Here's the same concept from the 1930's


Read more here;http://www.dself.dsl.pipex.com/MUSEU...aryValveIC.htm

I agree with those saying it has potential but there are issues that I'm not convinced have been overcome. The main one being the forces created in the combustion chamber acting on the rotary device during the combustion stroke creating friction. Convince me that's not a problem without just quoting the promotional material. In a convential setup (poppet valve) this force acts to seal the combustion chamber and isn't creating any friction.

[SSbaby]

Originally Posted by Raptor

I suppose you think you've stumbled onto something new and revolutionary here SSbaby? Here's the same concept from the 1930's

Not at all. It's just the first I've seen a working example of the rotary valve. Sorry if the story's actually over a year old, folks. Btw, there's lot's of different valve types about, with advantages and disadvantages for each configuration. It's just that the current cam actuated poppet valve system is very inefficient but still the most economical for our purpose. It's taken scientists and engineers over a century to try and better the current OHV and DOHC technologies, though without success.

If the rotary valve technology were that good, I'm sure manufacturers would seize the opportunity to launch it as it has fewer moving parts...

[svo347]

I agree its still interesting technology, I mean so is variable length intakes :P

[mcflux]

I'm still hanging for a flux capacitor (non-ebay) to come out on the market!

That valve concept is fascinating... Even if it is old-skool '30s stuff, by comparison the turbocharger was invented in 1925, and look how long it took before they became truly popular (80s/90s).

-Dave-

[Mike Gayner]

Give me BMWs Valvetronic technology any day. Tried and proven valve and rocker technology with a very interesting method of dynamically varying valve lift. Combine this with BMWs VANOS variable cam timing system and you have dynamically variable lift (0mm - 9.7mm) and dynamically variable cam timing (up to 60'). This, in my opinion, is the next best thing to a camless engine.

[SSbaby]

I wonder why the website hasn't been update since 2003?... http://www.coatesengine.com/news.html

This motorcycle has now passed the emissions test in 49 states and further testing is in the process.

George J. Coates, the Company's founder, stated that this diesel truck engine will undergo further testing and adjustments over the next several weeks.

[EFFalcon]

this is after 2003?

5/18/04

THIS IS A MAJOR NEWS UPDATE:

[SSbaby]

Originally Posted by EFFalcon

this is after 2003?

5/18/04
THIS IS A MAJOR NEWS UPDATE:

There will be approximately ninety days for negotiations, due diligence, contracts, agreements, etc. After which, all details will be announced when the contracts are completed and signed.

Well, that's over 90 days ago...

[outback_ute]

There was a rotary-valve head for Holden grey sixes in the fifties built by a guy by the name of Dunstan in South Australia, allowed the Grey motor to see 9000rpm apparently.

[Gammaboy]

My RG500 has rotary valves, however thats a slightly different form of the technology...
The thing I see that I don't like is the port shapes, and the fact that you can't control how fast the "port" opens... Its one of the reasons why rotary valved 2strokes were over-run by reed valved 2 strokes....
Sure, you can make the ports huge to overcome the poor shaping, but then you get low flow velocities etc. Nice Idea, sure it has applications, but not in high po cars

Bish

[MrSparkle]

If you can't get valve bounce with this then you're NOT TRYING HARD ENOUGH!!!

[svo347]

Originally Posted by MrSparkle

If you can't get valve bounce with this then you're NOT TRYING HARD ENOUGH!!!

There had to be someone...