Definition
Stoichiometric gasoline is about 14.7:1; richer mixtures cool combustion under boost.
Wideband sensors provide accurate AFR feedback for tuning.
Automotive Wiki
Fuel
Air-Fuel Ratio
The mass ratio of air to fuel in the intake charge, critical for power and engine safety.
Related terms
- Fuel InjectorAn electronically controlled valve spraying atomized fuel into the intake port o…
- CarburetorA mechanical device mixing fuel and air using jets, venturis, and throttle plate…
- Direct InjectionFuel injection directly into the combustion chamber at high pressure.
- Port InjectionFuel sprayed into the intake port before the valve, mixing with incoming air.
- Octane RatingA measure of fuel resistance to knock under compression and heat.
- E85A blend of roughly 85% ethanol and 15% gasoline offering high knock resistance.
Category: Fuel · Updated August 31, 2026