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View Full Version : What Is The Ideal PE A/F Ratio?



n8dogg
July 17th, 2010, 06:39 AM
I've heard some people suggest using 12.7 A/F ratio, some say 12.2 in hopes to get a true 12.7, and then I've read most power is found typically at 13.2-13.4. So that would mean 12.2 and 12.7 is too rich.

So what is a good target PE A/F?

johnv
July 17th, 2010, 07:14 AM
I usually aim for 12.8-13.0 AF and a touch richer at peak torque (4800-5200rpm).

But idealy you would use a dyno and see what your engine combo likes best.

WeathermanShawn
July 17th, 2010, 09:43 AM
For street I keep it 12.6-12.7 AFR. My engine seems to like it a little richer.

On the Dyno I kept it at 13.0, which generally equates to ~12.7 on the street (more load on street).

As stated, your own engine combo may be unique and require richer or leaner.

Good luck.

wesam
July 17th, 2010, 12:04 PM
I usually aim for 12.8-13.0 AF and a touch richer at peak torque (4800-5200rpm).

But idealy you would use a dyno and see what your engine combo likes best.
Do you make it richer at the peak torque from the PE based on rpm B3618 table or in the VE table or in the commanded fuel vs RPM B3647?

The Alchemist
July 18th, 2010, 07:18 PM
I aim for 12.7:1 at peak torque then lean off to 13:1 as you move past peak torque to the limiter. Every engines different though...you have to try it our really on the dyno. Seat of the pants dyno not quite good enough to tell the difference lol :)