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Rotary Valve Heads!!!


Moridin

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I have been thinking about this for years. I read about this type of valve when I was in high school, from one of my dad's high school text books. It is supposed to be extremely efficient, but as they said in the other thread, no one has been able to make it work for long periods of time due to wear and other issues. I would love to see what kind of power an engine with that type of head could produce.

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pic06.jpg

 

This from coatesengine.com. The RV heads were discussed in a Car Craft or Hot Rod article from over 5 years ago. I remember it pretty well and it stated that the engines can wind like no tomorrow because the heads are no longer holding them back. Think about it: no more "in & out" action, only spinning--what is the rpm limit?? :D

 

Here is another picture:

 

pic03.jpg

 

Davy

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They are currently used in heavy industrial use. The new-age Mustang guys (4.6L OHC design) are really pushing them to produce a set of heads. The 4.6L would actually fit in a Z, because the heads are so much smaller by the looks of it. I bet you could even fit a 5.0L or 5.4L cammer in there, making some insane amounts of power. No more worrying about adjusting timing to compensate for the time it takes to open a valve. Everyone should email them to push along an aftermarket set for a Ford.

 

Don't forget that they are producing a V-Twin Harley type bike with these rotary valves. SOOOOOO sweet!!!!!!!!!!!!!

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RPM limit???What RPM limit? :D:lol::D

 

It's probably based on the capabilities of the bottom end, a drop off point in efficiency of the rotary valves, or the flow capabiles of the head itself. In one of the articles, they said this:

 

"Since horsepower is defined as work over time, the CSRV allows for an extremely high rpm potential. Test run at Coates' facility have seen a Ford 5.0 liter engine spin to 14,750 rpm! Though the CSRV removes the valvetrain rpm limitations, the need to have a rotating assembly that can withstand the engine speed becomes the essential element. Another benefit of this design is the extended oil change intervals, with the lubricating system not being exposed to the rigors and pollution from the poppet valve."

 

About the power potential:

"Where the CSRV really shines is in its airflow potential compared to a poppet valve Bench-marking a 5.0 L engine from a Lincoln, the stock Ford casting (when tested at 28 inches of H2O) flowed approximately 180 cfm on the intake port at static. The rotary valve for the engine in comparison flowed a whopping 319-cfm at the same test pressure. Equipped with the poppet valve head, the Lincoln engine dynoed at 260 hp and 249 lb.-ft of torque. When equipped with the CSRV head at the same 5,500 rpm test protocol, it made 475 hp and 454 lb.-ft of torque, with no changes to the block or rotating assembly: The higher power was a result of diminished frictional and pumping losses, but the inherent airflow benefit of the spherical valve was the major contributor. With a conventional poppet valve, it can take 34 degrees of crankshaft rotation or more to reach a fully open position, wasting energy and limiting volumetric efficiency. With the CSRV, a comparable port area is exposed in only 2 degrees of crank rotation. The CSRV allows for superior surface flow coefficients from its spherical shape. With the standard 4-inch Ford bore, the factory poppet valve covers only 15.8 percent of the total bore area, while the rotary valve is measured at 20.5 percent."

 

And for others interested in alternative valvetrain design, try this: http://www.sixstroke.com/pageone.htm

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Equipped with the poppet valve head, the Lincoln engine dynoed at 260 hp and 249 lb.-ft of torque. When equipped with the CSRV head at the same 5,500 rpm test protocol, it made 475 hp and 454 lb.-ft of torque, with no changes to the block or rotating assembly

 

This one triggered my BS detector. No changes to pistons, compression ratio, etc.? This technology isn't new and, so far, it doesn't last. Its a great idea but no one's been able to execute.

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Actually they do execute. A guy on the SVT forums works for an industrial truck company that has an exclusive contract with Coates Engines for their big diesels. I'll look up the name of the company. You can order a motorcycle from Coates that will be out at the end of the year. I believe it's a Harley V-Twin with a set of Coates heads on it.

 

I wasn't sure at first, as my bs meter went off, but as I started to go through there site things became more believable. When they talk about spinning the motor up that high, they stated it would only do that with a properly prepared bottom end. The air flow change @ 5000RPM on the Lincoln motor is immense. I'll see what else I can find.

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  • 4 weeks later...

I first read about this when it came out in Popular Hotrodding.

I asked them about doing some testing for my senior design project. They declined. We had three superflow dyno's, with several V8's in various tune, all of which had the same bottom end. (It was a test for FI vs carbs among other things). In the end, after significant research for what I could find at the time, it was a very, very unproven project. The website is essentially the same as it was 4 years ago. I talked to them back in 99.

It seems clear to me they still have some issues, otherwise the major manafacturers, or at least some aftermarket folks would be jumping on this.

-Bob

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This has been done before. I "invented" this back when I was a co-op at Martin Marietta in New Orleans in 1988. The older British guy who sat next to me informed me that this had been done at various stages in ICE history. Some European automaker (Renault?) had a rotary-valved W-configured engine more recently, in the mid-90s. Nothing new under the sun, eh! It does seem to have a lot of potential. D.L. Potter once told me and a group of Georgia Z-club guys that an L-series valvetrain requires 150hp at 7000 rpm! So seemingly outrageous hp increases *might* be *theoretically* possible with this concept. Apparently it just isn't practical/practiceable. Yet. The piston ICE, she no dead yet!

 

P.S.: You want I should send your gloves to your home address, Bob_H?

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Heh, thats funny Dan. I "invented" this setup in about 1992 as it just came to me one day. A couple years later I saw my "invention" in a magazine and learned that they have been around since the 60's. :P

 

I still think the theory is very sound, and there is a big performance gain available from such a setup. Whether the Coates system is as good as it sounds, I don't know. I would expect sealing to be a major issue around a spherical valve... however, there are lots of industrial ball valves that can seal around a sphere. Heat + Pressure + a good seal might be tough however.

 

Still, a very intriguing concept to me.

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  • 2 weeks later...

Wait a minute. I "invented" this too!!

Actually I saw a 2 minute blurb on a sports news show one time many years ago which showed an F1 or indy car type of chassis blazing by and casually mentioned rotary head testing at a track during some other event. From that I quickly figured out how it might work and designed (on paper) a version for the Briggs and Stratton engine on my go kart. I spent a couple weeks working out the details and put it in my crazy ideas file. With my engineering/manufacturing experience now I bet you could make a hell of a go kart engine outta that that would last long enough for a season of racing.

anyway yea it's a cool idea with production issues. I bet if someone got serious they could make them work nowadays, looks like Coates is close. Who woulda thought the poppet valve would work the way it does after 100 years of development?

Another thing to think about is even if they can't last as long, what's a rebuild gonna cost on a cylinder head with 1 or 2 moving parts?

I'd like to see one with that variable compression system by mounting the cylinders on a pivot and EFI and Cam timing with a supercharger. I bet you could make an engine with great mileage and lots of power and even adjust how aggressive it sounds at idle etc.. to suit your mood.

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I was at a paved hill climb last weekend that had a lot of classic cars. One was a tiny motercycle twin engine with rotary valves. Pre ww2. It sounded really cool and seemed to have a lot of torque for what it was.

 

Douglas

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Actually, Kawasaki has a whole line of motorcycle engines with rotory valve heads, been makin em since the 60's. This is a cool application for a V-8 though. I wonder with modern oils and materials, if we won't see a major manufacturer put out a v6 soon with rotory valves!

 

from Amazon

 

"Kawasaki 80-350Cc Rotary Valve, 1966-2001 (Clymer Motorcycle Repair)

by Clymer Publications Staff, Jeff Robinson (Editor)

 

 

List Price: $28.50

Price: $19.95 & eligible for FREE Super Saver Shipping on orders over $25. See details. "

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  • 1 month later...
Actually, Kawasaki has a whole line of motorcycle engines with rotory valve heads, been makin em since the 60's.

???

Really? Not to be the skeptic, but show me a website about these motorcycles rather than a book. I have had some rather extensive discussions about these valves, but have found no other references. I would appreciate any pictures, etc...

-Bob

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Bob_H

 

You have every right to be sceptical, as I clearly don't know what I am talking about. Well, sort of. As it turns out, the Kawasaki engines are 2-strokes, which, as I am sure you are aware, have completely different valve requirements than a four-stroke. The rotor valves replace the reed valves, and would certainly not work for a four stroke engine. I have just started learning a little more about these engines, as I recently aquired my first motorcycle. I'm getting close to 30 now, and I guess it's an early mid-life crisis thing.

 

Anyway, you're right in that this is not really applicable to this discussion. That'll teach me to go around posting crap I really know nothing about. Good luck with your investigation of the rotory valves!

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