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Old 02-04-2010, 11:58 PM   #16 (permalink)
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Moderate your Moderation.
 
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Quote:
Originally Posted by El Duende View Post

I'm gonna see this WAI thread that you speak of. You can't seriously be putting in one of those for a leaner A/F ratio. I wouldn't feel too comfortable with my car running leaner than it already does from the factory. (14.7 or so) In the event that you do need to run in open-loop, acceleration will surley suffer. How hot do you want your engine to operate, anyhow?
Internal combustion engines, being of the adiabatic sort of beast family, are inherently more efficient when they're "soaked" closer to combustion temp. The hotter intake air is proven to be more efficient per volume of intake because there is less tendency of the combustion heat to soak into the engine (the engine has already reached equilibrium with the intake air, so less heat is pushed into the metal on combustion because of the already higher cylinder wall temp), and less energy from heat necessary to increase the temperature of the intake volume.

There have been published studies which show these, and other examples, as benefits of increased engine temperature and intake air temperature, where efficiency is concerned.

To clarify the term - Efficiency, in this case, is the amount of energy derived from an amount of fuel during combustion, compared to the actual energy content of the consumed amount of fuel.

The WAI in general doesn't lean the A/F ratio - it reduces the dynamic displacement of the engine, and reduces pumping losses. A less viscous fluid is ALWAYS easier to move. (Air is a fluid.) And since less mass will fit in a given volume when the temperature is increased, the engine sucks in less on the intake stroke, further reducing pumping losses.
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