The uncle jack method (works for us, but no guarantees) is to raise the
float level as high as you can without starting the car on fire (or flooding
it). We think we run 4 psi at the moment, but would like to lower it a
tad. We also drilled a couple more holes in the jet tube, I seem to recall.
The Stromberg has a rather shallow float bowl compared to the SU's, and on
the SU you can turn the float bowl so that the fuel pushes on the float in
the direction that gets the fewest g's. What I'd really like to see is the
SU float bowl on the Stromberg carb.
- Tony Drews
Bill Babcock wrote:
> There are kludgy fixes. You can pipe another pickup point between the
> float bowl and the jet holder (the banjo). I saw that done to a
> motorcycle carb (amal monobloc) years ago, and the guy claimed it
> worked. then again, I always thought he was full of shit. But the most
> likely way to get by is raise the float level to the upper edge (or a
> little beyond) of spec, and use a bigger float needle and seat. Raise
> the fuel pressure a little tiny bit--the things that get the float
> chamber filled quicker but still keeps the needle and seat in control of
> level.
>
> I generally run the float level high even on Webers, and then set up the
> jetting so it's right with that inherently richer starting point. It
> reduces the likelihood of fuel starvation. But then you MUST use a fuel
> pressure regulator because you are closer to flooding the engine--you
> can't live with a 3 to 5 PSI swing. The float has a smaller range of
> motion to work through, and therefore has less closing pressure on the
> needle when the chamber is overfilled. If fuel pressure is holding the
> needle off the seat initially, a low float level means the float may
> still be able to shut off the flow as the level rises. The seat pressure
> increases as the fuel level rises because more of the float is
> submerged. If there's enough room before the fuel starts running out of
> overflows or through the jets, then the car will behave semi-ok.
>
> -----Original Message-----
> From: Barr, Scott [mailto:sbarr@mccarty-law.com]
> Sent: Friday, January 29, 1999 3:12 PM
> To: 'Bill Babcock'
> Subject: RE: Fuel System Questions
>
> dang.
>
> > -----Original Message-----
> > From: Bill Babcock [SMTP:BillB@bnj.com]
> > Sent: Friday, January 29, 1999 5:21 PM
> > To: Barr, Scott
> > Subject: RE: Fuel System Questions
> >
> > Yup.
> >
> > -----Original Message-----
> > From: Barr, Scott [mailto:sbarr@mccarty-law.com]
> > Sent: Friday, January 29, 1999 2:35 PM
> > To: 'Bill Babcock'
> > Subject: RE: Fuel System Questions
> >
> >
> > SUs would have this same problem, correct?
> >
> > > -----Original Message-----
> > > From: Bill Babcock [SMTP:BillB@bnj.com]
> > > Sent: Friday, January 29, 1999 4:38 PM
> > > To: Barr, Scott; 'Friends of Triumph' (E-mail)
> > > Subject: RE: Fuel System Questions
> > >
> > > This is a very common problem with certain carburetor designs that
> > > have
> > > the fuel pickup from one side or the other of the float bowl.
> > Raising
> > > the float level or increasing the float needle size (where feasible)
> > > sometimes helps a little, but the only cure is multiple fuel pickups
> > > or
> > > a concentric arrangement of fuel reservoir and emulsion tube. One
> > > would
> > > think that the fuel would not be affected that much, but a cross
> > > section
> > > of the fuel in the float bowl of a car turning at .5 G would show
> > the
> > > fuel surface at a 45 degree angle--the float needle is held shut
> > while
> > > one side of the bowl is dry.
> > >
> > >
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