Anyone know how to figure out an equivelant BSFC?
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You can make an attempt at monitoring it using the following formula (the validity of the result will depend on how close your sensors are to ideal)
HP = IFR * 8 * DC / BSFC
BSFC = IFR@(Baro-MAP kPa) * 8 * InjDutyCycle / HP
(if you use HP values from a chassis dyno the values will not be comparable to normal BSFC values).
Alternatively you can try using the delivered torque paramter on the pcm as such
BSFC = IFR@(Baro - MAP Kpa) * 8 * InjDC / (Torque * RPM / 5250)
The units are normally expressed in lb/(hp*hr) (in the US anyway) - depending on what units you use for your injector flow rate, well, you will get the resultant BSFC in terms of those units.
I have no idea how accurate the formulas above will be, as I have never tried them - but without an engine dyno that is the best you can do.
You can replace the fuel injector term (IFR * 8 * injDC) with your MAF rate and calculate your BSAC the same way also.
Chris
HP = IFR * 8 * DC / BSFC
BSFC = IFR@(Baro-MAP kPa) * 8 * InjDutyCycle / HP
(if you use HP values from a chassis dyno the values will not be comparable to normal BSFC values).
Alternatively you can try using the delivered torque paramter on the pcm as such
BSFC = IFR@(Baro - MAP Kpa) * 8 * InjDC / (Torque * RPM / 5250)
The units are normally expressed in lb/(hp*hr) (in the US anyway) - depending on what units you use for your injector flow rate, well, you will get the resultant BSFC in terms of those units.
I have no idea how accurate the formulas above will be, as I have never tried them - but without an engine dyno that is the best you can do.
You can replace the fuel injector term (IFR * 8 * injDC) with your MAF rate and calculate your BSAC the same way also.
Chris