This is something I have been watching from afar for a couple years and am somewhat dis-heartened that it hasn't become more available or publicly tested. A truly high-tech upgrade away from the conventional "poppet" style vale head. I stumbled across it when I had a similar idea and started jotting down rough draft sketches. I thought I would share it with the board and see if anyone else has seen it or something like it. Maybe if someone is in the New Jersey area they could take a recon trip and post their findings. click herehttp://www.coatesengine.com
is this the one that removes the parasitic drag of the cam and valve train and puts in the head with the use of special valves. chaz
Yeah, it removes the cam, lifters, pushrods, and replaces them with balls on a shaft that have holes cut in them to allow intake/exhaust. They claim it eliminates 90% of the drag and parastatic loss of a traditional camshaft set up.
I think this was tested about 10 years ago on indy car style engines (high reving) If I recall correctly they were running into problems completely evacuating the cylinder of exhaust gas. something about the valve not being able to open long enough in relation to the stroke. and they would run out of room on the ball to fully seal the chamber in relation to the duration of the stroke. however It may have been an engine where the same ball opened the exhaust and intake ports. it is a very neat idea however. -nate
There are a few statements on the Technology page like this one: "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." Most running at 12 to 1? Really? That is a bit different from the factory info of 9.5 to 10.25 to 1 for most every V8 produced during the 60's and up to 1970. Or this one: "...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." Turbos and superchargers DO NOT significantly increase the speed of the mixture. They primarily increase the VOLUME thereby creating pressure and power. Or this last one: "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." Yes, most of these systems have additional moving parts and, yes, they will eventually wear. I have to believe however, that these systems have been engineered with piston/valve interference issues considered and resolved. This kind of exaggeration really puts me off of a product. If it is as good as the manufacturer says, why in the world would these statements be necessary? It's like the old snake oil or magic medicine salesmen. All kinds of claims for how wonderful the product is. I guess I would have to see an independent test by a trusted person such as Jim Burek or the guys at TA to believe the claims made on the Coates web site. o No:
I have one of their brochures from about a dozen years ago. Most of their prototype engines were Fords. Yeah, the cut-away photos were cool.
Awesome feedback GS, I understand some mechanics, but not enough to accurately judge stuff like this or to raise too many intelligent questions. Schurkey, I have some info coming to me in the mail as well, it would be interesting to see if it has been updated over this timeline. I did call them and asked them for the info. The receptionist said at this time you could buy a license ????? to put it on your vehicle (what ever that means). I also sent Dr. Evans an e-mail in which I asked for some dyno data comparing poppet vs shperical valve, since they are marketing v-twin bikes i would expect them to have this information.
Another instance of the PHD mechanical engineer friend of mine's .02. According to him just about everyone at some point played with these rotating cylinder type intake/exhaust arrangements. If I remember correctly the problems are: 1. The flow rates are not good 2. The opening event is too "soft". You need a certain amount of turbulance to keep the fuel/air mixed. Someone probably made an engine that ran on this principal 60 years ago and ditched it for a reason. regards
1. The flow rates are not good yeah, looking at the way the port path twists through the valve, it doesn't look to me like there's a good way to get airflow velocity... but ianae :idea2:
kinda the same concept a corliss steam engine.. KINDA... those were MUCH more effecient than the regular stephenson link valve gear.. i dn't know how much more effecient they were over a poppet valve steam engine though... here i am comparing steam engine technology with infernal combustion technology ou: wes
I had the same thought, that's why my original idea would be that the spheres would have a straight through hole. The hole in the sphere would be turned 90 degrees from the piston for the compression stroke. Any thoughts??
The hole in the sphere would be turned 90 degrees from the piston for the compression stroke. Any thoughts?? o No: what i thought of a couple of years ago was a cylindrical rotating intake log over the cylinder bank. obviously fed by forced induction from the ends. more than two cylinders/bank would probably result in starvation issues for the center cylinders though. i don't know if the check-valve like arrangement you're considering would result in enough time on the valve opening. if something like that were implemented i think i would want to go with independent ball/cylinder valves actuated by a computer for fully control of valve timing throughout the rpm range.
I finally got a reply from Coates regarding their product. Here is my e-mail to them and the reply, read into it as you like Dr. Evans I am writing in inquiry to the spherical rotary valve system you have produced. I have been wondering when we could expect to see this in a mass produced market to the general public. I am just a car guy that is fascinated by the obvious potential in the spherical rotary valve system. I didn't know if you already have some direct bolt on replacements for some motors, as I assume could be done on an overhead cam model engine, or if there are plans on converting a cam in block motor to the overhead spherical valve type of induction. I am personally involved with working on mostly small block Chevy's and big block Buick motors. I do see that there is a motorcycle engine that is on the market. I would love to see any kind of information on dyno tests before and after the Coates conversion if available. Thanks for your time and I anxiously await your reply, Sincerely Jim Moore May 11, 2007 Mr. Moore, your May 9th email reached us, and it is a pleasure to hear from you. At this time we are unable to tell you when the general public will be able to purchase the CSRV system. Our auto program is on a temporary hold so that nearly all our efforts are being directed into other projects: industrial generator motors for use in gas/oil fields, pumping a large truck engine, home generators, and complete motorcycles. We have not printed any product catalogs or pricing sheets for use in soliciting orders from individual motoring enthusiasts, and there are no plans for making ones or twos of single engines because the cost to the consumer would be exorbitant. We regularly receive emails from motorists who seek the SB Chevy or various larger CD GM engines, but until we finish a large portion of the workload associated with the other applications mentioned above, we will be unable to revisit the IC auto engine vista. In time it is likely that we will return to this category, but no action has been taken by the Board of Directors about opening the Coates Motorsports Division, which is unfunded at present. Our bikes are still being evaluated by an independent laboratory so we are unable to make any comments about their performance characteristics: RPM, BHP, torque, mileage, emission, etc. When the data becomes available, it will be placed on our website. Thank you for contacting the Coates organization. Please visit website www.coatesengine.com so that you may read the postings that will appear there to inform the public of changes in our product development. Sincerely, Dr. Richard Evans, Director ***this is them ----->:blast: shooting it down
Shooting it down for a while at least. Maybe by the time gas gets to 8 dollars a gallon they'll "fund" the auto division. As a stockholder tho it sounds promising. Their putting all their eggs in the utility and large transport engine basket. Still I was hoping to be able to do some cheaper and faster:3gears: sometime soon with these vavles. I've been watching Coates for a long time and for the same reason you have been, my idea was a disc shape laying flat but using oil for lubrication. I got all jazzed up when they went public that i'd be seing an ad for their conversion kits in the gearhead mags at wal-mart soon. So much for that.
As an FYI, I am still waiting for the literature they said they would mail to me....... what a disappointment
