SU
SU carburetor catalog. Includes SU carburetor kits and other related carburetor parts.
In Stock
ID .176" OD .316" THK .070"
Part Number G273
(1)
$1.95
If you are a true classic car connoisseur then
SU carburetors will be familiar to you. If not, don't worry. The team of
specialists at Mike's Carburetor Parts has prepared this short article for your
enjoyment.
Although the Skinner brothers, Herbert and
Carl, patented their innovative variable venturi design in 1906, it was not
until 1910 that they finally succeeded in founding Skinner Union Company
Limited. This is how the famous SU carburetors were officially born.
Unfortunately, the company began its
activities in a stormy era, just before World War I which forced the Skinner
brothers to make the decision to sell the business in 1936 to their main
client, Morris Motors. The new company, SU Carburetor Company Limited, part of
the Morris organization was much more fortunate, as it soon became the official
supplier of MG vehicles, as well as a major supplier of Rolls-Royce, Bentley,
Rover, Riley, etc. Turner, Austin, Jaguar, Triumph, Volvo, and the Saab 99.
Its high quality and reliability, in addition
to being a major supplier of the most luxurious and sophisticated vehicles of
its time, earned SU carburetors a reputation that they retain to this day.
Carburetors were once responsible for
delivering the right amount of air/fuel mixture to the engine, and to achieve
their mission, they had to overcome many challenges. Possibly one of the
biggest of these challenges had to do with how to regulate the mixture under
different driving conditions, idle, cruise speed, acceleration and
deceleration.
In that sense, SU carburetors provided an
innovative yet bold solution. Constant depression technology.
Constant depression carburetors like the SU
are based on a variable venturi that is controlled by a piston. In turn, the
piston worked as the metering rod (needle) whose seat was the orifice that we
know as "jet" and whose movement was controlled by the air flow that
passed through the carburetor. This simple system made it possible to control
the amount of fuel that entered the carburetor under the different driving
conditions in an efficient way, since it automatically "adapted" to
driving needs.
Among the main advantages of SU carburetors
are:
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Ease of adjustment, thanks to its
“pseudo auto calibration” ability.
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Simplicity, since they do not
require multiple jets like conventional “fixed-venturi” carburetors
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Fewer moving parts which translate
into higher reliability
Although SU carburetors were perfect for daily
driving vehicles, their principle of operation was not without some
disadvantages
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Since SU carburetors restrict free
air flow, they are rarely used on high performance applications.
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The lack of an acceleration pump
further reduces the viability of these carburetors in high-performance
vehicles.
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The piston requires to be filled
with light oil that has to be replenished in a timely manner.
Between 1937 and 1972, SU introduced a wide
variety of carburetors to the market, most of them aimed at the most
prestigious British car brands.
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H type carburetor: the original SU carburetor
introduced in 1937 by the S. U. Carburetor Company Limited and used in many
Morris cars.
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HD type carburetor: introduced in 1954, the
new design included a rubber diaphragm integral with the main jet.
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HS type carburetor: four years later, in 1958,
the design changed again to include an external flexible pipe to transfer fuel
to the carburetor (in previous designs fuel went through the arm into the
carburetor body)
?
HIF type carburetor: a radical change was
introduced in 1972 with the incorporation of an integral horizontal float bowl.
Looking for parts for your precious classic
car? Then look no further. At Mike's Carburetor Parts we offer high-quality,
hard to find parts such as SU Carburetor Needle & Seat, SU Carburetor Kits
for Austin, Hillman, MG, Riley, Jaguar, Morgan, Rover, Triumph, Vanden Plas,
Volvo, Wolseley, and more.
Your car deserves the best, specialists who
are passionate about restoring your carburetor to "like new"
condition. At Mike's Carburetor Parts, we have the best advice for all kinds of
requirements you may have.