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Old 09-10-2012, 04:34 PM   #17 (permalink)
Daox
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Quote:
Originally Posted by Diesel_Dave View Post
The benefit is coming from two places.

First, increased vol eff decreases the pumping work. This is because as the piston moves down during the intake stroke it's being pushed down by the incoming air. The higher the air pressure during the intake stroke, the lower the pumping losses. Higher vol eff means higher in-cylinfer pressure during the intake stoke--even though the pressure in the intake manifold may be the same. The second source of the benefit is from the increased combustion efficiencies due to the higher AFR.
Is there really measurable gain there? Deisel engines optimize both of those thing better than most other engines already.
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