Rotary Valves

NYSpeed Automotive
1

gotta say, this is news to me. Figured it would be to some other peeps here aswell. This is one of the most obvious and ingenious things I’ve ever seen (next to the supercooler). :tup: :tup: :tup: from me

http://www.coatesengine.com/

I want to see it up close and check it out.

think about it… if you want more flow on a standard cammed engine you probably want to port the head(s), change the valves, cam(s), springs, ect, ect, ect

with this, if you are already running this system, just swap out the valves and be done with it

edit: I wonder what the drawbacks are though?

2

There was a discussion on this on a few other boards a while back. Seems like a great idea but it dosent really work as well as it is claimed.

The company has never released any actual horsepower figures. When asked they were “unable” to produce any leakdown figures.

The only horsepower figures the company was able to produce is that of an 833 cubic inch 280 hp CNG motor. Thats less than 10 hp/l.

This idea is actually not new its pretty old. Its a variaton of the Cross Rotary Valve System developed in the 1920’s.

http://www.dself.dsl.pipex.com/MUSEUM/POWER/RotaryValveIC/RotaryValveIC.htm

The problems with rotary valves were all the same… They never sealed correctly.

The advantage of a poppet valve is that the higher the cylinder pressure the better a poppet valve sealed because it is pressed against the valve seat.

All other valve systems have the opposite relation. In that the higher the pressure the weaker the seal.

The problem that has not been surmounted yet is how to seal the chamber during the combustion cycle.

3

The only horsepower figures the company was able to produce is that of an 833 cubic inch 280 hp CNG motor. Thats less than 10 hp/l.

damn lol thats pretty bad. I’d like to see it on a standard gasoline engine (same “lift” and “duration” as stock) and see what they get.
I think I’d give it a shot if the price was within budget, but the whole sealing thing does make sense. But with todays technology with percise machine tools, I dont see how they couldnt get a tolerence that would almost eliminate that (then again, that would drive the cost up)

4

They could get the tolerance but it would seize itself as soon as the engine warmed up. As soon as the engine started depositing carbon it would also cause problems.

5

good point… hmmm, I see how it can be a problem. maybe some kind of treated steel/aluminum (heat treated or what have you) and/or some kind of coating

6

actually… I’d like to see this on a small displacement v8 (2-3L)… bet you could rev the piss out of it lol

7

this has been around for a while now and it will rise and fall on its seal design

8

everyone pretty much covered the same conclusions i came to about it and why it won’t work efficiently.

  1. carbon deposits after a short time gumming everything up and increased friction
  2. never a good seal … and definatley not good for a high hp setup where increased cylinder pressures are always present.
9

I dont know, like I said… I’d still lile to see some #'s/test results

10

^^^

We have been waiting since 2003 for those numbers apparently the engine makes so much power that they don’t want to release actual figures for fear that us motorheads would die of a heart attack.

11

I’ve done alot of reading on those valves, and they had a SBF that revved to 15,000 before the bottom end let go. It would be great if the aftermarket bought the technology, but they are pricing it for the OEM’s. It could change what we know about cyinder head design. Its been around for 8 years or so that i’ve known, and i think that it might be a proto only part for many more years.

12

in development since the 70s in one form or another

13

This thing keeps popping up, huh Don. :rofl:

14

fuck you

15

:mamoru: