The invention relates to a method for producing a value T being representative of the mean engine torque generated on a crank-shaft of an internal combustion engine, comprising 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 P.sub.x, 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*P.sub.x, where k is a polynomial constant. The invention also relates to a device for producing a value T.