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Old 11-02-2011, 10:56 AM
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Fudman Fudman is offline
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Originally Posted by bluebee View Post

That description makes it sound more like a 'valve' than a 'fitting'?

Wow. I just realized, reading your explanation, that the big fat drum that is in 'most' cars for power brakes, doesn't exist in the E39!

Does the SJP take the place of that thing?
It is literally a fitting, like the F connector. It is not a valve because it does not open or close. It is always open. However, instead of a smooth inside channel of consistent diameter, the fitting has a nozzle like constriction. This causes the airflow to accelerate to squeeze through a smaller opening. The faster airflow causes a pressure drop (much like faster airflow above a wing surface causes a pressure drop and lift to occur). The SJP doesn't replace anything and draws a vacuum on the "big fat drum" which does exist. See Steve's post for the picture.
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