Is targeting a 14.6:1 air-fuel ratio under all conditions a valid tuning strategy?
Not at wide-open throttle.
- Cruise and idle: stoichiometric (about 14.7:1 on pump gas) is the normal closed-loop target. The computer deliberately swings slightly rich and lean around it, which is what lets the catalytic converters work (HP Academy).
- Under power enrichment: the WOT target is much richer than stoichiometric (HP Academy). Factory calibrations run a little richer than best power as a safety margin against lean damage and low-octane fuel (LSX Magazine).
Holding 14.6:1 at wide-open throttle would go against both. See tuning fundamentals.
Want to do it yourself? See who tunes it, and how to learn.
Confidence: medium — sources disagree or are limited; check the sources below.
Community discussion
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Sources
- 199 | Optimising Your Tune Using Short & Long Term Fuel Trims (STFT + LTFT) — High Performance Academy
- LS Tuning For Optimum Performance — LSX Magazine