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      01-16-2012, 07:13 PM   #181
Poor Kid with Dreams
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Drives: BSM 07 E90 335xi
Join Date: Aug 2010
Location: Danbury, CT

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Originally Posted by shiv@vishnu View Post
When viewed as a working system (engine+turbo+induction+exhaust), VE will change. The lower exhaust back pressure (afforded mainly by the big turbine housing) will improve the pumping efficiency of the engine. If the VE of the engine alone will not change of course but that isn't really worth discussing since the engine is just one part of the system.

Ah, gotcha. I didn't think about the fact that it will take less exhaust pressure to push the same turbine at a lower speed that will produce the same amount of boost. I'm not sure how much this would increase VE, though. Does this engine have any overlap while in boost? I would think not...

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