 As a result of the tendency of the engines to smoke and hence give away the tank positions, Harry Ricardo was brought in, and devised a new engine which replaced the sleeve valve starting with the Mark V tank.Among the companies using Knight's technology were Avions Voisin, Daimler (1909–1930s) including their V12 Double Six, Panhard (1911–39), Mercedes (1909–24), Willys (as the Willys-Knight, plus the associated Falcon-Knight), Stearns, Mors, Peugeot, and Belgium's Minerva company that was forced to stop their sleeve-valve line of engines as a result of the limitations imposed on them by the winners of WWII, some thirty companies in all.Itala also experimented with rotary and sleeve valves in their 'Avalve' cars.