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Simulated injector pulse output


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Is it possible to simulate an output that would show injector pulse width?   I’m looking for a digital dash output so my cluster can calculate fuel mileage.   The factory dash takes into account the fuel in the tank, as well as the injector duty cycle to calculate miles remaining and MPG.    I’m running a link Thunder with sequential injection and COP for a 8 cylinder.   The factory ecu and dash are coded for 19lb injectors but if I could get the signal and modulate it to take into account my ID 725’s and dial it in.

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It might be as easy as sharing a Injector output. We do this on the GTR R34 to keep the center consul display happy.

The catch with this is it wont scale for the bigger injectors. SO the next step would be to use a GP PWM and se the table up to span off injector duty. 

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A couple of GP PWM examples below, the first one will send out a pulse that matches the injector pulse (roughly once every 2 revs, roughly same duty cycle as the injector).  

Since you have bigger injectors and want to tell the instrument that there is more fuel flowing than it appears from the duty cycle I think I would try adjusting the frequency table (so it sends the pulse more often - since you cant send more than 100% DC anyway).

This first set up would give the same signal as effectively "teeing" into an actual injector wire:

CepioDk.png

 

 

Since your new injectors have about 3.6X the flowrate of original, we could send the "pulses" 3.6X more often by doing this:

Y9hY47C.png

 

It's hard to know if this will work as we dont know if the instrument already takes RPM into account from the tacho signal or it uses this same fuel used pulse.  But worth a shot.  

 

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