REFLECTOR: Fuel Flow Sensor

[NMFlyer1 at aol.com]

I have a question on my fuel flow sensor placement. 

My setup is a little different than most Velocities. My 173 FGE has a 
2-electric fuel pump manifold with an inlet line, engine line, and regulated return 
line. The regulator keeps the engine pressure side at 25psi, the rest "T's" 
back in before the inlet line but after the filter. 
My fuel Injection is on TOP of my aluminum V-6. All the plumbing is on the 
cabin side of the firewall except from the bulkhead fitting to the fuel servo. 

The instructions on the flow sensor say that it needs to be placed with the 
wires in the "up" position, and that a "reasonable" straight section of tubing 
proceed the sensor inlet. 

It also recommends that it be placed after the fuel pump(s). 

I don't have a reasonable area where I can meet all the requirements and the 
recomendation that it be after the pumps. 
I can place it in front of the sump, 6" downstream of the sump elbow, with a 
straight run after that meets all the requirements. The flow is then up to the 
fuel filter, through the recirculation "T" and to the pump inlet. What it 
does not do is place the sensor after the pumps.  I do believe it is far enough 
away from all the pumps/recirculation line and filter to avoid any turbulence 
that would confuse it. 

Since the recirculation takes place after the sensor, and returns after the 
sensor (and well downstream), It measures the amount of fuel that leaves the 
sump. This should equal the amount of fuel that the engine is using (barring a 
big leak!).

 I can not think of a reason that would require the flow sensor be after the 
pumps in my setup, unless there is some flow concern that I am missing. 

The exit line from the pumps runs upward from the pumps, through the pressure 
sensor "T" and to the firewall bulkhead connector. 

Any input would be appreciated. 
Kurt Winker
173 FGE.... bending fuel line.
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