This problem for me has been an absolute pain, I originally had my flow scan mounted in the tunnel, after the boost pump and before the mechanical pump.After reading a previous post I decided to move it to the engine bay after the mech pump. But on my engine with horizontal induction it was not possible to put it in the recommended position between the fuel servo and the flow divider, so I thought I would put it in the second best place as recommended, that is, in the line from the mech pump to the fuel servo. But this also proved to be also extremely difficult. In the end I decided to put it back were it started, in the cabin. Safety was the main consideration here.
The other reason for moving was that it was reported that readings were inaccurate with the boost pump on, but I have to ask why this would be so? A flow meter measures flow and as such the transducer would not know what pressure it was operating at (and within reason wouldn't care). On reflection, I would say that if the readings go up with the boost pump on, it is because more fuel is flowing hence no inaccuracy. Thoughts on this please