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Old 05-10-2008, 12:25 AM   #75 (permalink)
Duffman
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Quote:
Originally Posted by LostCause View Post
Also, I don't understand why a turbocharger doesn't decrease pumping losses, at least on the intake stroke. If the intake manifold is above ambient, doesn't that mean the absence of pumping losses?

- LostCause
Because gasoline engines are throttled to limit power when low power is desired. The manifold is still under vacuum up until 100% volumentric efficiency (its probably 85% because most NA engines cant fill thier cylinders 100%) so there is still pumping losses.

I write this under the assumption we are comparing the same engine pre and post turbo.
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