Mark.. I ran my Roedel models CT114 Tutor with the smoke outlet in the scale position ,, never had a problem , made great smoke ... I simply ran a 3/8 0/D brass tube right down the pipe in between the outer and inner pipes out to the end of the exhaust tube and then curled the outlet up into the center of the the exhaust stream about one 1/2 inch out from the end of the pipe and installed a brass cap with side outlets made from a Robart schrader valve air inlet , looked scale and worked very well......MK