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RarlyL8 RarlyL8 is offline
Crotchety Old Bastard
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Join Date: Jan 2000
Location: Huntsville, AL
Posts: 13,551
No, what I am saying is the RPM switch is a good bandaid but does not actually fix the problem, it masks the symptoms.

The problem is that as the WUR ages it goes off spec. In order to recalibrate you need to go inside the WUR and do some adjusting. Once back in spec you re-gain the full spectrum of the threshold adjustment.
The RPM switch simply delays the onset of boost by hiding the signal until a preset RPM, effectively overriding the threshold system by shifting the threshold to a point requiring less adjustment. The resulting A/F graph looks better but the WUR is still off spec.
RarlyL8 Motorsports / M&K Exhaust - 911/930 Exhaust Systems, Turbos, TiAL, CIS Mods/Rebuilds
'78 911SC Widebody, 930 engine, 915 Tranny, K27, SC Cams, RL8 Headers & GT3 Muffler. 350whp @ 0.75bar
Brian B. (256)536-9977 Service@MKExhaust Brian@RarlyL8
Old 04-02-2008, 02:00 PM
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