Graham Knight writes:
> What is the theory of operation on an SU Carb??
SU's are a "constant depression" carb. For a real feel on this British
phenomenon, you must read (or see) the "Hitch Hikers Guide to the Galaxy"
series (or movie) by Douglas Adams. Refer your attention to Marvin the robot.
In breif (very), constant depression, or constant vacuum carbs vary the air
opening to maintain a constant vaccum- To see what lifts the piston you need
to follow the air passages, and think about vacuum created by airflow...
Lifting the needle out of the jet richens the mixture by "enlarging" the jet
opening (skinnier at full lift.)
Alternatly, the first chapter of the Haynes SU manual has a very good theory
of operation. I'll get around to my own version one of these days...
________
/___ _ \ Roger Garnett (Roger-Garnett@cornell.edu)
/| || \ \ Agricultural Economics | The Wayward Sports Car Centre
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