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Re: [Herald] carb fitment questions

To: "Donald H. Locker" <dhl@mrdog.msl.com>, <spitfires@autox.team.net>
Subject: Re: [Herald] carb fitment questions
From: "Wayne Burton" <Wayne_burton@bc.sympatico.ca>
Date: Sun, 15 Aug 1999 20:40:21 -0700
>Donald wrote

>Any good reference material available on 948 Heralds, especially
>under-bonnet stuff?

The factory shop manual for the Herald, Spitfire and Early Vitesse is the
manual
 for you. It is listed under part number 511243

>What did the intake and exhaust pipes arrangement look like on a 948cc
>Herald?  I searched the archives and the web but hits on Herald 948,
>and SU H2 were pretty sparse.  And it looks like H1s were original on
>this motor.

The herald 948's use solex downdraft carbs. The 948TC used the optional HS2
setup, but it was pretty rare. This being the same as fitted to the early
Spitfire4.

>How were the choke links connected?  None of the pictures I have show
>linkage like I have -- the brass arms for lowering the jets are
>identical on the front and rear carbs.  I arranged them to point
>toward each other, but I have no idea how they should be actuated and
>coordinated.  (I'm tempted to connect a loop of cable, one end to each
>arm, and just pull in the middle of that.)


The twin carbs are actuated by rods between the paired throttle plates, and
the
choke actuating plates. The rod rotates in concert with the pulling of the
choke
cable on the rear carb, and operates the front carb.



>How was the accelerator pedal attached to the throttle on this
>vehicle?  (I'm assuming that this really came from an Herald.)  The
>Spit linkage won't fit through the exhaust pipes.  I'm considering
>fitting a cable linkage.  Sound reasonable?


Since the herald used an actuating rod for the linkage, the linkage is by
rod
from under the carbs. The rod pushes up on the center of the actuating rod,
and operates
both carbs. There should not be a clearance problem from under the carbs.

>Should I try to fit the HS2 carbs instead?  I would have to fabricate
>an intake extension to get more clearance between the carbs and the
>exhaust pipes, but the rest looks simple enough.


Yes. This is what they should have. The extension is in the form of an
insulating block,
about 3/4" thick. It is stock on all early spitfires.

>Here's what I have.  1969 Spitfire MkIII, 948cc motor (1296cc motor
>currently in cryo storage, awaiting resurrection,) choice of SU H2 or
>HS2 carbs.  The 948 manifolds appears to be cast steel; intake and
>exhaust are all one piece.  (Looks like a mold was made from a
>fabricated-from-tube assembly and cast; surface is clearly sandcast,
>but weld marks are clear enough wherever pieces meet.)  Intake has
>normal front and rear carb mounting positions which fork on the way to
>the head.  Exhaust looks just like a header, but cast.  And they are
>all cast together.


This is a very strange combination. It sounds homemade. Does this casting
have "Stanpart" embossed on it anywhere??? I doubt it. All manifolds I have
ever seen
have been two part, and the only car triumph used a 'header' on were the Mk
II spitfires.
and the works cars.

Why does your car have a 948cc motor? These are _very_ rare here. Mostly the
early spits
had 1147 motors. What is the engine id number. (Serial No.)  All early cars
had siamesed
intake ports so there were only two intakes to the head.

It sounds like this is an interim solution to the correct motor in the
future. In this case, I would
proceed to make the modifications as required for the 1296cc motor. You will
still need the spacer
but you'd probably be better off getting an OEM header for the 1147 (Mk II)
and fitting it to the 1300
later. And the OEM intake manifold sounds to be in order too. (Sorry, I only
have the Mk I intake/Exhaust
and they are made of unobtanium, so you can't have them!)

I am e-mailing you (off list) the carb set-up from the spitfire4 1147 for
reference. It should help.



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