(engine with Coates rotary spherical valve system [CRSV])


(pic of the spherical valves in the cylinder head)

I was lookin through some engine developement stuff i had layin around, and i stumbled across some papers on Coates spherical valves. I was wondering if anything ever got put together for chevy engines. Basically the heads designed by Coates eliminated the cam, pushrods, lifters, rockers, cam gear, valvesprings, retainers, locks, and valves themselves, and replaced them with spherical roller valves that are setup similar to the way DOHC's are. Due to removing a TON of weight by practically eliminating the valvetrain, and by lessening friction and wear, this system is extremely efficient, and can result in HUGE power gains. I know Coates developed a Ford version of this system, but i don't think it was ever produced. I guess this is basically just to inform you of it and ask why this never took off, i'd love to get my hands on it

http://www.coatesengine.com/technology.html

 

$$$$ would be my guess.

 

Cool setup, but after you give them your arm and both legs, how are you going to drive it??? LOL

 

That's pretty cool. If anyone has any info on it, I'd definately be interested too

Matt

 

money is always an issue, i'm sure it wasn't cheap having 4v heads made either, but it was done. you'd think that they'd have race teams jumpin all over them wanting this setup.

 

Re: heads



, your March 2nd email was received, and it is a pleasure to hear from a potential customer. The auto program is “on a temporary hold” as I write this reply, and no automotive catalogs or pricing sheets have been prepared. Right now all resources are dedicated to mating the worldwide patented and protected CSRV system with a line of large industrial engines which will run on a variety of fuels. Only when management brings these engines to the market will new initiatives be announced. While most of your questions will have to wait until auto engines are released to the public, I can tell you that the intake manifolds are an integral part of the Coates design and should require no undue amount of maintenance. We recognize the merits of the L 98 small block Chevy engine you’ve inquired about, but the time for CIL to jump into this market hasn’t yet arrived. Thank you for contacting the Coates organization, and periodically check in with our website www.coatesengine.com to watch for postings which will inform the public of changes in our product development schedule.



Sincerely,



Dr. Richard Evans

Director

DRE: jmg

This was the reply I got when I email them

 

PHR had a decent article about these heads on a SBF 3-4 years ago. Coates then stated they had SBC heads "in the works" and should be available for a little over $15,000!

 

A little to rich for my blood. Then again, for the prototype highend exotic stuff that kind of price tag is expected...

 

The reciprocating valve train mass is eliminated as well as the rotational camshaft mass, but what gets added is a lot more rotary mass in the form of those golf ball spherical valves. I don't know how it compares math-wise because I haven't analyzed both. Those spherical valves are going to act like balance shafts that aren't intended for balancing purposes, so there will be frictional loss added. (Balance shafts are known to absorb some of the engine power, and balance shafts don't have friction-causing seals on them, whereas the spherical valves shown here do).

I can also imagine that keeping the exhaust side valves de-crudded from combustion products would require some special seals. It's a neat idea, but it's not obvious to me that there is an advantage. I'll have to look over the web site for more details.

 

OK I looked their web site over.

This article was interesting:

http://www.coatesengine.com/lookmom_noCamshaft.htm

but I have a few questions. First, they compared the 5.0 liter Ford engine to the same engine using the Coates cylinder head with the rotary valves, and showed huge gains in hp and torque (260 hp and 249 lb.ft of torque on the stock Ford, and 475 hp and 454 lb.-ft of torque when using the CRSV head). The differences in the tests are vague though, because:

1. cylinder head combustion chambers (stock vs CSRV) are different, and so both the swirl and compression are likely to be different. They should have explicitly stated the differences.

2. the stock Ford engine uses stock valve timing so the flow into the engine is limited by the stock cam (stock duration, stock lift).

3. the CSRV head uses a valve duration for intake and exhaust that were not specified, so we have no way of knowning just how much extra duration the CSRV test got. The flow characteristics of the CSRV head could be compared directly with the stock Ford head/cam by showing the profile of the coefficient of discharge for each valve as a function of the crankshaft angle, as well as showing the actual flow vs crank angle.

3a. AFR heads on a stock 5.0 liter (Mustang) Ford have been dyno'd at over 400 hp (a recent auto rag did this) so better heads obviously yield better dyno numbers --- so perhaps the difference in Ford vs CSRV is more due to the superior flowing CSRV head and bigger IVO/IVC EVO/EVC durations than it has to do with rotary valves.

4. what were the engine efficiencies for both test configurations? What were the BSFC for both as a function of rpm? They used a dyno, they claim superior emissions, so this should be child's play for them to measure and report the results.

The CSRV head is clearly innovative (based on an old idea btw --- rotary valves are not new), but there are details missing and I'm a skeptic. I also wonder how it would function for 100,000 miles in real world situations. My $0.02.