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Question about the poppy valve system for an internal combustion.

Question about the poppy valve system for an internal combustion.

Question about the poppy valve system for an internal combustion.

(OP)
Question about the poppy valve system for an internal combustion.

I see lately that more and more people are getting concerned about the environment.
Many companies including the auto industry are jumping in on this movement with eco friendly cars such as elect and hybrid models.

My question is this, why haven't they done more to improve the valve system that is currently in use ( Poppy valves with springs) ? With all the springs that eat up horse power one would think that they would come up with a zero float valve system by now.

Is it simply the cost of re-tooling and training?

I would think that creating a new elect or hybrid model would be more expensive.

Lennyc
 

RE: Question about the poppy valve system for an internal combustion.

A poppy is a flower.  The resin from its buds has more commercial significance than the flower itself, and is more responsible for its worldwide cultivation than is the beauty of the flower.

The word you seek is "poppet".  Like the flower, it is the result of many generations of evolution.  Alternatives have been tried, and surely more are possible, but they will have to deal with the same evolutionary stresses.

Springs do not dissipate significant amounts of power.  Engines have been built without them, and have met with modest commercial success, despite other related problems.  Google "desmodromic" or "desmo" or "Ducati desmo".  

Re-tooling is but one of the evolutionary pressures facing any technology.  You clearly mis-assess its significance with "Simply ...".  It's not just a question of equipping the worldwide set of service operations with appropriate hand tools.  Tooling also includes the machinery that's necessary to make tens of thousands of units a day in order to support a reasonably successful vehicle line.

 

Mike Halloran
Pembroke Pines, FL, USA

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