Manual Injector PWM control

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wheeler_express
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Manual Injector PWM control

Post by wheeler_express »

My engine will operate from sea level to altitudes exceeding 20,000 feet, where the air is much less dense. Also, during cruise it is often very advantageous to lean the mixture to well below the 14.7:1 to extend the range of the flight. The air is so thin at high altitudes, that it often takes 60 to 70% of the power to get the same speed as at lower levels. Also, during takeoff, we often run quite rich to help cool the engine until we get more airflow.

So, I would like to see if I can install a simple POT for this manual adjustment. Center on the pot will be "0", the low range will be lean, the high will be rich.

Which file would be the best for this?
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Fred
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Re: Manual Injector PWM control

Post by Fred »

Put it on the MAT pin, setup a table with a linear slope, and apply a correction based on that data with some limits (+/- 20% ?). That easy. It really is trivial to do something like that, there are other challenges that await you :-)

fuelAndIgnitionCalcs.c is the file for the calcs
TestTransferTable.c you could repurpose for your pot profile. IE, use a linear pot but make it as aggressive/mild as you want, with an arbitrary ramp.
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