Jeff Spitzer wrote:

At 11:19 AM 6/3/99 -0700, you wrote:

Ken Powell wrote:

I am trying to decide if a small header tank (say 1/2 gal capacity)
will cause a significant rise in fuel temps for an EFI engine.  Since
the fuel pump will deliver apprx. 40 gallons per hour and the engine
will be burning apprx 8 or 9 gallons per hour, the refresh rate of
fuel from the main tanks is about 20%.  This means that 80% of the
fuel has been thru the EFI fuel manifold up to 4 times.  Do these
numbers look reasonable?  Since the manifold is hot, the fuel will be
heated on each pass.  Is this a potential problem or maybe only a
cause of a small lose of power due to a lower fuel density.

     Thanks,
     Ken Powell

Don't forget about the heat from the fuel pump itself.  These little gems
typically convert less than 20% of the electricity to pressure and flow.
Further, the pressure and flow that you bleed across the regulator becomes
heat.  Hot fuel has higher vapor pressure and is susceptible to
cavitation/vapor lock.  Recirculating too much fuel to a little tank is not
a good idea.

Jeff Spitzer

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