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Old 08-24-2009, 08:51 PM   #15 (permalink)
Christ
Moderate your Moderation.
 
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Quote:
Originally Posted by Frank Lee View Post
I've already made my decision.



That energy used to compress springs, minus friction, is largely recovered when the springs decompress.
I don't think this is correct, Frank - the valve stems don't act on the cam to keep it in motion, the springs only act as a way to keep the valves seated and closed unless the cam is acting on them. This is part of the reason that solenoid engines are so much more efficient (not by any means 50%) than cam driven engines.
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