This document discusses formulae considered applicable to aircraft engines having integral supercharging without aftercooling, and using gasoline introduced at the entrance to the supercharger or directly into the cylinders. Such engines are normally designated as single and two speed engines. Correction formulae for engines having two stage or exhaust turbo supercharging will not be discussed. Corrections for engines having a high degree of integral supercharging will be discussed in general terms only and no specific formulae will be presented.