Re: How to measure fuel use with return to tank sy
To do it the "right way", www.matronics.com makes a return fuel flow computer that can take 2 sensors, subtract their outputs, and send one out to the EMS.
This probably won't work for you, because your EFI setup probably doesn't have a constant return flow rate, but there is a configurable "return flow" number that lets the EMS subtract a CONSTANT FLOW from the actual measured flow. So it's a constant return flow number, expressed in terms of pulses. So if you're looking to tell the system that there is X gallons per hour returning to the tank, you'd take your primary K factor, multiply it by the number of gallons per hour, and that would be your return flow number in the EMS. If you're using the Matronics, you don't use this number at all by the way.