a/f ratio concern

[neon angel]

14.7-15.0 stock right?
13.5 is rich or lean?


on a aem what is idle ,wot and criuse?

[INVUJerry]

You have an NGC car. Your A/F will always be at or close to 14.7:1. 13.5 is rich. You will not make any more power tuning your a/f richer, of even if you do, you will not feel it due to your ATX.

[neon angel]

yes i relize i have an ngc but look at my dyno sheets i add fuel and made it to 13.5 cuz for some reason my upstream o2 is shot even when i replace it ,it still run super lean/

[racer12306]

numerically less than 14.7 is rich

numerically higher than 14.7 is lean

[DaveHill]

Actually, If you want your car to be optimized for performance, 13.0 or 13.2 :1 is what you're looking for a NA setup.

14.7 is the stoechiometric value for a perfect mixe of O2 and Hydrocarbon. But with a 13.0 or 13.2:1 You will have faster flame propagation in your combustion chamber.

[turbodudey]

14.7 is the stoechiometric value for a perfect mixe of O2 and Hydrocarbon. But with a 13.0 or 13.2:1 You will have faster flame propagation in your combustion chamber.

Eh... no.

Running richer than stoich will result in slower flame propagation. That's one reason some people run richer to help avoid detonation.

Any engine (turbo or N/A) will always produce maximum power at 12.8 AFR, and max torque at 13.2 AFR.

If fuel quality is good enough (high enough octane rating to avoid detonation) 12.8 - 13.2 would be the richest you'd ever have to run. Often though, to avoid detonation a richer mixture is required.

Cruise afr can be as lean as 15 -16, depending on timing.

Idle afr depends on temperature. Cold idle = 13.5 or so, hot idle = stoich. (approximatly)



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