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Is 11:8:1 too rich for BBSC?

23 October 2000
Saint Augustine, FL
I am going to do a little tuning with the car. Currently it runs about 11.8 at WOT.

Where should it be?

Basically yes, that is a good air/fuel for a FI stock motor'd car, assuming its a stock compression motor... It leaves a little safety room for durring a long multi gear pull where your temps may rise...
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The rule of thumb that has been posted many times on PRIME (and I read in an independent forced-induction tuner's guide book) is between 11.8:1 and 12.2:1. Due to the dynamic nature of air-fuel ratio data points, there will never be a "flat line" of AFR value. You can import the data from your engine management controller.....Split Second, AEM, Haltech, Motec.....into Microsoft Excel. Therein, you can perform a few keystrokes that will calculate the arithmetic average of AFR over whatever RPM range is desired. However, just because the overall average is, say 12.0:1, there will be a few spikes above and below. A couple of spikes around 11.7:1 and a couple of spikes around 12.3:1 generally may not be avoidable. What is very important is to make data logs of the wide-band O2 sensor, and look for an extended "trend" of being too lean nor too rich.....concentrate on these RPM bands.