> If you are going
> to have a boost pump (highly recommended if your RV-3 is using wing tanks)
> --------------------
>
> ===>  Hi Ed.  So I guess they have more suction than advertised.  I will
be
> using wing tanks, with no header tank, so why do you highly recommend a
> boost pump?  I don't see the purpose, especially if the EFI pumps are
> located below the fuel level.
>
> Rusty
>
 Good question, Rusty.

   I guess I do it because I'm kind of a belt and suspenders type guy.  But,
here is my rationale,

Reason 1: is that I found on a few occasions when I used MOGAS on a HOT day
with a longer than normal ground time, I could tell the fuel was percolating
(fluctuations in fuel pressure).  Turning on the low pressure boost pump
provides enough head pressure to eliminate it. Your set up may be such that
you don't need to be concerned about vapor lock - but, I have that small
header tank on the firewall.

Reason 2:  Should your line go dry (run a wing tank dry - I umm have done
that on occasion - sometimes even intentional {:>)), the boost pump seems to
fill the empty fuel line quicker - could be just perception since I've never
timed how long it took to get fuel pressure back by either method..

Having stated that, by your decision to mount your tanks on the floor below
the level of your wing tanks, I wouldn't think you would have problems.

Ed