A method for producing a value T being representative of the mean engine torque generated on a crankshaft of an internal combustion engine includes the steps of producing a speed vector including values being representative of instantaneous speeds of the engine during a sampling period, determining a mean engine speed n during said sampling period from the speed vector, determining a value Px, being representative of the frequency contribution of the speed vector at the frequency x*n, where x is a pre-selected order, and producing a value T being representative of the mean engine torque on the crankshaft during said sampling period, wherein T is derived from a mathematical expression including a polynomial having at least a term k*n*Px, where k is a polynomial constant. A device for producing a value T is also disclosed.