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RarlyL8 RarlyL8 is offline
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Join Date: Jan 2000
Location: Huntsville, AL
Posts: 13,410
Garage
Yes, the pressures should be set to the middle of spec for the engine type number if the engine is stock. My factory manuals don't go to '86 but I was not aware that any 930 had a stock control pressure greater than 95psi. What is different about the 930/86? Typically you need a higher system pressure for high performance. The '86 US has less HP than the Euro '79.
In this case though it doesn't matter. The WUR is not adjustable. If the warm pressure is off, the engine is stock and and you wish to keep it stock then you must purchase another WUR with the same part number.

The mixture screw only affects idle mixture/baseline. You need to check the warm pressure then the boost pressure to determine that the WUR is in fact faulty.
As for the cold start issue, a high cold pressure is lean and vice verca. How does your engine act when started cold? Does it put-put-put to life or fire and idle slightly high as normal, but taking longer to do so?
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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 07-08-2008, 01:43 PM
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