What we
need is some expire mental measurement of flow rate under actual
conditions (which will involve a flow meter in the system) and then,
with the engine at rest (the pump is the only moving part in the
system), we can see how much current it takes to achieve that flow rate.
Sadly, the pivotal instrument, a flow meter that doesn't disturb the
system too much, is probably not available.  If someone could come up
with a flow meter in a 1.25" line, we could do some expirements.
Other than that, we're guessing at numbers like PL and the bumblebee
folks ... Jim S.

I agree.  Everyone keeps talking about all this head pressure that the pump is having to face.  It must be stealth pressure, because my pressure gauge doesn't see it. 

As I type, I'm also looking for a suitable flow meter, and I'm open for suggestions.  The plan will be to rig this into my system, and find out once and for all what sort of flow I've got with both the mechanical, and EWP.   I doubt there's any way to have this in place during flight, so Ernest will say it's not valid :-) 

So don't make this too painful, but lets here some options for suitable meters. 

Rusty (Todd has already done all this of course)