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Old 01-24-2008, 07:34 PM   #4 (permalink)
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Originally Posted by plym49 View Post
In order for the engine to produce the same power, given the smaller valve opening, then I will need a larger throttle opening. This reduces pumping losses, slightly improving volumetric efficiency.
It may improve volumetric eff at certain loads, but in terms of the pumping losses that result in the largest efficiency drop in gassers, it won't do anything because those are a result of limiting the amount of air to enter the cylinder. This can be done via a throttle, or valve, but as long as the cylinder can't completely fill up with gases efficiency will suffer. Honestly, the only improvement I think you could count on from something like this would be what you could see from limiting your right foot.
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