Strombergs are indeed as British as the London Bridge.
The story is actually quite funny. It started in the end of the 50's
Triumph got their SU carburettors from SU in Birmingham. (SU was already
part of BMC then).
But they charged Triumph twice as much as they did for the same carburettor
set up for MG!!
Harry Webster (head engineering at Triumph) set up an idea of developing his
own carburetor.
It had to be of a constant vacuum design because he thought this was the
best principle.
(and he is right... I think)
The difficulty was that SU had certain patents so some redesigning was
necessary.
In the new carburetor the non patented SU features were carried over. The
rising piston and needle were totally redesigned. This is why the Stromberg
has a membrane. In 1960 the prototype was ready.
It proved very expensive for Triumph to produce the carburetor though and so
the project was handed over to Zenith and this is why the carburetor is
called Zenith-Stromberg. Stromberg was a trade mark taken over by Zenith
some years earlier.
Thus Triumph designed the Stromberg carburettors and handed the design and
production over to Zenith. The first Strombergs were used in the TR4's at
the end of 1962.
The SU is better for performance though because it lends itself better for
polishing and enlarging its ports. It also has far more variety in needles
and such.
Adriaan Briene
http://members.tripod.com/~RoverSD_1/index.html
On our SD1 homepage we are busy with an SU page, coming up soon.
For now check out our Lucas/Bosch L-jetronic pages in the TECHTALK section,
including working principles, diagnosis and testing.
Vereniging Rover SD1 vrienden
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