What if...
you forgot the fuel flow sensor, since it's unreliable after all. And is hard to find... And replace that with a vacuum sensor that gives voltage according to how much engine is loaded.
Plus take rpm reading as mentioned above. Combine those signals in MPGuino code and you might have a economy gauge of some sort. As you might know the "modern EFI systems" often relay on vacuum x rpm signals (and temperature and AFR) when controlling the fuel amount.
What would still be missing is the use of a choke. That is difficult to measure. And of course the carbs are not too linear gadgets supplying the fuel...But anyhow you could do A-B-A testings with warm engine.
I have an old Zemco fuel computer in my summer vehicle. And I have been trying to calibrate it for about 5 years. Most of the false readings were caused by bubbles in fuel (heat) and the mechanical pump and the displacement of fuel filters and everything else.
Once you think it's quite accurate, it will stop reading in the middle of your most important test run ever.
