noun
theoretical air-fuel ratio; stoichiometric air-fuel ratio
Technical term used in automotive and combustion engineering. Refers to the chemically ideal ratio of air to fuel for complete combustion.
ガソリンエンジンの理論空燃比は約14.7です。
The theoretical air-fuel ratio for a gasoline engine is about 14.7.
Compound of 理論 (theory) + 空燃比 (air-fuel ratio). The exact historical derivation is uncertain; the term is a modern technical coinage.