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patkeefe patkeefe is online now
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Join Date: Apr 2004
Location: Ringwood, NJ
Posts: 2,850
I have the same problem you described with the IA head and BL WUR. This is the advanced tuning part, I suppose. We have plenty of fuel delivery. Although I have SC CIS, it is the same as 930, more or less. I believe the WUR sees boost pressure on one side of the diaphram, and reference pressure on the top fitting, with reference being atmospheric in the photo of your WUR. Brian Leask's RPM solenoid switch cuts the boost signal to the WUR until a pre-determined RPM. Of course, where we get boost signal pressure from is another variable. You will get different signals from locations either before or after the throttle plate. I have had some discussions with BL regarding this, and I will have to find my notes. I think if you were to connect vacuum to reference, it would make the WUR believe it was under boost, as it would want to pull up on the top of the diaphragm, as opposed to bosst, pushing up on the bottom of the diaphragm.
Patrick E. Keefe
78 SC
01 Boxster
Old 03-14-2009, 10:21 AM
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