That quick engine running the Dog Bone is a hybrid Marx 1998 frame, motor and wheels with a Lionel NW2 cut down shell with a repaint job.
The Marx1998 and this hybird Marx 1998 / Lionel NW 2 switcher are a great running engines and always beats other engines in racing through the oval and figure 8 and the Dog Bone. The Marx 1998 is the best running engine I have for racing. It has a two way e-unit and is light and will out accelerate all and stay on 027 curves and go thought Marx 1590 switches. It helps that is is a 2-4-2 with front and rear integrated trucks. My kids, now adults still love to race them as I have another one too.
Charlie