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RarlyL8 RarlyL8 is offline
Crotchety Old Bastard
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Join Date: Jan 2000
Location: Huntsville, AL
Posts: 13,527
What instrument are you using to measure your A/F ratios?
Do you have a precise way to measure and record boost vs RPM in all gears and situations?

The reason I am asking these questions is that in order to optimize the RPM trigger setting you need to know the absolute lowest RPM that your engine will see 0.4bar of boost. That RPM will change given variables such as ambient temperature, what gear you are in, and intercooler efficiency.

Once you know that target RPM you can set your trigger and lock everything down. It's a crude device but it does reduce the enrichment spike that can hit in the 10's for some engines.

To directly answer your question, 13.0 @ 4000 rpm is probably OK. That is where mine is at as well. By 5000 rpm you should be in the high 11's to low 12's and stay there to redline.
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 05-31-2007, 07:02 PM
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