I did fuel flow tests on my old pump gas Duster due to not being able to jet it up rich enough to slow down the MPH in the 1/4 mile. I had a Magnafuel 275 (suppose to feed 750HP)pump on the car and bought their 300 pump that was rated at 900 HP, my moto had a six pack set up on it so I flowed the pumps with all three flex lines into a five gallon plastic fuel jug for 10 seconds three times on the 275 pump first and then the 300 pump after swapping them out, no noticeable differences in the flow
I call Magnafuel the next morning and told them what I had tested and they told me that I needed to either do the tests with the fuel bowls attached to the lines or put a restrictor in the lines to load the pumps, don't test unrestricted. I decided to hook one line back to a carb and redid the flow test three time, it gain over 40 % flow increase through two lines on those three tests
I ended up finding out that the 10 micron fuel filter I had mounted between my gas tank and the fuel pumps was restricting the fuel flow into the pumps
I ended up putting the 275 pump back on the car and it worked fine plumb like Magnafuel said to plumb it
Sometimes we need help on figuring things out, huh