Thread: Super MPGuino?
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Old 08-20-2009, 01:54 AM   #9 (permalink)
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Originally Posted by gtkid2002 View Post
The multiple injectors was just an idea I threw out. If it would help make the gauging even more accurate, why not? But if it's not going to make much of a difference, who cares. I could possibly see the need of something like this on a V-8 that has the cylinder shutoff, but i'm assuming that would require a lot of code tweaking and a lot of vehicle-specific engine data.
As i understand it, you only need one injector pulse per cycle, because you are calibrating the # of pulses over an entire tank of gas. It makes no difference whatsoever to your calibration, whether you pulse once per 360 degrees (on the distributor), or once per cylinder. The value will either be 1 * N, or exactly X * N, where X = # cylinders and N = # times cylinder 1 fired over the calibration period.

You raise an interesting point with the cylinder shutoff option. Just throwing this idea out there, for comment by those who would know better than I:

Could each injector be tied to the single 'duino input line, by placing a protective diode onto each one? If so, your calibration and tracking would be based on the exact # of pulses, as required by 'shutoff' engines, instead of the once-per-cycle that most of us need. Would the diodes prevent the separate injectors from cross-talking or shorting each other out?
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