The Spitfire 1500 competition manual does say the 3.5 - 5 PSI, but they also
are talking about quite a few modifications to the ZS carb in conjunction
with this. Plugging holes with epoxy, using modified float spindles,
replacing ZS needle with SU needle, thinning of throttle shaft, and a bunch
of other stuff I understand even less than what I just quoted. I would not
assume that the pressure should be increase in the absence of all the other
modifications they propose.
77 Spitfire (with very happy carbs recently rebuilt by my friendly
neighborhood LBC mechanic - best $60 I ever spent!)
62 TR3B (years away from even needing carbs)
[mailto:firstname.lastname@example.org]On Behalf Of Joe Curry
Sent: Friday, May 01, 1998 7:01 PM
To: Edward Hamilton
Cc: Mark Milotay; email@example.com
Subject: Re: Spitfire Fuel Flow Rate
Does it say what carb. setup that is for? I recall reading (but I can't
for the life of me remember where) that the 2-4 psi setting is correct.
I recently was having a problem of too much pressure and that resolved
it. I checked briefly in the Haynes book and didn't see anything.
Maybe it was in the notes that came with my carb. rebuild kit. I'll
look further as I get time.
Edward Hamilton wrote:
> According to the Spitfire 1500 Competition Preparation Manual, "A fuel
> pressure regulator should be mounted on the firewall to enable fuel
> pressure to be maintained at 3.5 - 5 lbs. sq./in."
> Ed Hamilton
> Joe Curry wrote:
> > Mark,
> > Do you have an electric fuel pump, perchance? If it is one of the
> > late
> > model universal ones, it will put out way too much pressure (on the
> > order of 15psi. I believe that somewhere between 2 and 4 psi is the
> > recommended pressure for SU's. I run my HS2's at 2.5.
> > Joe
> > Mark Milotay wrote:
> > >
> > > I was wondering if someone could tell me the correct fuel flow
> > pressure for
> > > an '80 Spit, running dual SU HS4's? I have a flooding problem that
> > new
> > > floats and grosse jest have not solved. The car is still running
> > like a
> > > broke dick dog. It gets progressively worse the longer you drive
> > the car,
> > > then improves after sitting.
> > >
> > > Thanks,
> > >
> > > Mark
> > --
> > "If you can't excel with talent, triumph with effort."
> > -- Dave Weinbaum in National Enquirer
"If you can't excel with talent, triumph with effort."
-- Dave Weinbaum in National Enquirer