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Old 01-18-2013, 12:58 AM   #253 (permalink)
christofoo
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Quote:
Originally Posted by t vago View Post
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However, if we assume that we keep available work per firing cycle constant, we have to increase the available work per firing cylinder to cover the lost available work from the deadbeat cylinder. This requires that the firing cylinders' produced work must increase, which means more fuel being consumed by the firing cylinders in the firing cycle.
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I don't think we've reached the same page just yet. We're still stuck on the step: going from 4 cylinders firing to 3 cylinders firing.

With 4 cylinders firing, the available work and pumping losses are exactly met by the produced work.

We're not going to change fuel input yet (EDIT: fuel input per cycle), we're going to redirect fuel from 1 deactivated cylinder to 3 active cylinders.

Pumping losses have not changed yet. We had 4 cylinders before deactivation and there are still 4 cylinders after deactivation that are all experiencing the same pumping loss. Inlet and outlet pressures have not changed yet. Total cycle pumping loss has not changed yet.

Produced work is dictated by a set amount of combustion components, which are not going to change because the fuel per cycle hasn't changed yet. The AFR is broken right now but we're going to fix that in the next step.

The next step is to adjust manifold vacuum to correct the AFR.

Last edited by christofoo; 01-18-2013 at 01:34 AM..
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