Cold fuel

[Tom Sharpe]

Fuel system is mostly 3/8 steel tubing w/ flare ends from your local auto supply
joined to AN fittings and press on 300 psi hose - the goodyear blue stuff - for
vibration/connection to fuel rails. The tubing flare is 45 deg and the AN is 37
deg but never had a drip and it's been apart a-lot.  There is a ferrule joint in
the middle - didn't have to flare the tube.  The tubing has a make connector,
but when you cut off one end and remove the threaded pieces, you can use the AN
female tubing ends...

Bruce wrote:

> You've hooked up a visual flow guage and have seen this, or are guessing?.
> If you vapor locking fuel at 35 PSI there are some serious issues.
>
> Last I hear the low end aromatics were about 130dF flash temps., and that's
> at atmospheric pressure.
>
> If you fuel temps are approaching an actual operating temp of 120, I'd be
> looking for some Firebraid.  Are you using lots of AN?.  AN has been
> nicknamed the Heat Magnetic with some people.
>
> Some oem fuel routing is just flat dumb, ie in 3rd gen Fbods (CCC), the fuel
> line runs with in 2" of the trandy for 2'.  Up in the tranny tunnel is great
> place for heat to accumulate.
> Bruce
>
> ----- Original Message -----
> From: "Tom Sharpe" <twsharpe at mtco.com>
> To: <diy_efi at diy-efi.org>
> Sent: Wednesday, October 17, 2001 10:22 PM
> Subject: Re: Cold fuel
>
> >
> >
> > Bruce wrote:
> >
> > > With wet manifolds, might have a problem with the fuel being too warm
> (also
> > > remember in carb applications you have to allow for fuel volume).   So
> they
> > > can have ****TOO**** much of a good thing (vaporization).
> > >
> > > On EFI (port), just about the opposite is true.  You can have trouble,
> er,
> > > you can sometimes improve performance by aiding with fuel vaporization.
> > >
> > > If you look at the latest GM manifolds, and heads you can see where they
> are
> > > making a real effort to get as much fuel on the back of the valve head
> as
> > > possible.
> > >
> > > Honda F1 in years last ran a fuel preheater, to aid in vaporization.
> > > Bruce
> >
> > On a 95 deg summer day running around elkhart lake for 60 min., after 45
> min.
> > everything was hot - track temp > 120, the fuel in the rails boils when
> you let
> > off the gas going into a corner and the fuel pressure drops to match the
> engine
> > vacuum. When you step on the gas exiting the corner, it's just like a carb
> w/
> > vapor lock. it takes about two seconds full throttle to clean out the
> rails....
> > maybe my bigger fuel pump will make the problem worse.  IMHO, heating the
> fuel
> > will produce better mileage/power/combustion, I like the new, non-recycle
> efi
> > fuel systems. The bypass ones really heat the fuel... Tom
> >
> > --------------------------------------------------------------------------
> --
> > To unsubscribe from diy_efi, send "unsubscribe diy_efi" (without the
> quotes)
> > in the body of a message (not the subject) to majordomo at lists.diy-efi.org
> >
> >
>
> ----------------------------------------------------------------------------
> To unsubscribe from diy_efi, send "unsubscribe diy_efi" (without the quotes)
> in the body of a message (not the subject) to majordomo at lists.diy-efi.org

----------------------------------------------------------------------------
To unsubscribe from diy_efi, send "unsubscribe diy_efi" (without the quotes)
in the body of a message (not the subject) to majordomo at lists.diy-efi.org