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Old 06-08-2010, 06:14 PM   #2 (permalink)
dcb
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ok, vacuum computers are painfully slow compared to electronic ones. They don't make a whole lot of o2 sensors that output in vacuum so you have to add electronics to a carburetor just to make a rough approximation of stoich.

A wideband o2 sensor with the right EFI software can hold stoich, or any mixture that makes sense, over almost the whole operating range. A pure carb cannot adapt, if you change elevation you run lean or rich. If it is moist out, your mixture is affected, or if the temperature changes, or if the composition or temp of the fuel changes.

feedback is a good thing when done right. and a EFI can also "lead the target" in some cases, rather than lagging the airflow, with some random amount of additional fuel squirted in when you move the pedal.

I'm not saying all EFI were done terrifically, but all were able to pass emissions that a carb couldn't touch, due to much finer control over the fuel delivery.
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Last edited by dcb; 06-08-2010 at 06:29 PM..
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