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RarlyL8 RarlyL8 is offline
Crotchety Old Bastard
 
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Join Date: Jan 2000
Location: Huntsville, AL
Posts: 13,526
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Every setup has its "sweet" spots. There are so many different cams, turbos, exhaust systems, A/F ratios, variables in general. The timing and CO affect the spool down noise you hear from the turbo when the ignition is shut off. For a "mild" engine the spool down noise goes away when the tuning is dialed in. That has nothing to do with the delayed fuel cutoff of the 930 pumps that can cause the chug to a stop phenomenon, separate issue.
I typically set the timing at 26* initially. Once the CO is set at 3% you can wiggle the timing a bit to find that "sweet spot" where it all comes together nice and does not detonate nomatter what the temperature is or grade of fuel used. Others may chime in with a different method.
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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 08-01-2007, 05:18 AM
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