Question about Zero float valve design in Desmodromic valve actuation.

Here's a link below if anyone needs to refresh there memory on what's a Desmodromic valve actuation is.
http://www.wheelsofitaly.com/wiki/index.php/Desmodromic_valve

My question is this, if this zero float valve system saves on horsepower just how much horsepower does it take to work the conventional poppet valve system? Say on a 6 cylinder engine each cylinder having 4 valves.
Also does anyone know of any research reports I can see or download on zero float valve systems for the internal combustion engine?

I very interested in learning about just how much horsepower can be saved using this system and what other benefits there are.

A desmo valve system is better in some respects and worse in others, than a conventional coil spring and cam system.

The desmo system has lower friction losses while the valve(Reducing Valves) is being opened and closed, at most engine speeds, since the cam-to-follower friction losses are only as high as the valve inertia forces.  On the other hand, a spring and cam system has friction losses that are higher than necessary at low engine speeds because the spring force (or rate) is optimized for high speeds.

Conversely, the desmo system has higher friction losses during the period when the valve is closed, since the closing cam and follower must always maintain a force on the valve to keep it seated.  A spring and cam system does not have this loss, since the spring keeps the valve seated and no contact is required between the cam and follower.  Thus it has no friction losses during this period.

Overall, the desmo system is likely slightly more efficient.  But not normally enough to offset its greater cost and complexity.

With regards to valve float, this is not usually a problem for modern poppet valve engines, except at very high operating frequencies.  But if you're truly concerned about valve float, I'd suggest that a pneumatic valve spring system would outperform a desmo system, and would be less complex.

No matter what the design is, a conventional coil spring, ovate, bee hive, multi spring etc. will always have surge at various frequencys. That can add to valve train loading etc. I think desmo has a conventional spring beat as far as stability goes. A conventional valve springed valve can chatter ie bounce on the seat, also causing such things as valve head separation, seat face hammering etc. 

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