Fuel Consumption calculation accuracy

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Fuel Consumption calculation accuracy

Postby Spinner on Thu Mar 01, 2012 8:29 pm

If you use Fuel Inj duty % to calculate fuel used, what is the estimated accuracy of this calculation?

I'm using 6 x Bosch 340 cc/min injectors.
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Re: Fuel Consumption calculation accuracy

Postby TunedByShaneT on Wed Apr 04, 2012 5:39 pm

Anywhere from quite accurate to not at all.

This largely depends on;

Linearity of your fuel injectors throughout the dynamic operating range
Accuracy of battery voltage offset for your injector at the fuel pressure you are running
Flow variation of your injectors to each other throughout the dynamic operating range

Better accuracy if you calculate the injector duty cycle using Effective Pulsewidth rather than just the reported duty cycle. Still need the above items to be correct however.
Regards,
Shane Tecklenburg
Technical Consultant
ST Consulting
21602 Surveyor Circle
Huntington Beach, CA 92646
714-318-5845
shaneteck@yahoo.com
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Re: Fuel Consumption calculation accuracy

Postby Holmz on Wed Apr 04, 2012 8:33 pm

TunedByShaneT wrote:Anywhere from quite accurate to not at all.

This largely depends on;

Linearity of your fuel injectors throughout the dynamic operating range
Accuracy of battery voltage offset for your injector at the fuel pressure you are running
Flow variation of your injectors to each other throughout the dynamic operating range

Better accuracy if you calculate the injector duty cycle using Effective Pulsewidth rather than just the reported duty cycle. Still need the above items to be correct however.


Is there a write up or webinar on this?
I got 4 graduated cylinders, and would like to go through the process.
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