There is a setting for motor type selection-the can motors in the SD-80's be a small or large motor. I would say the pittmans in a steamer would be a large type, the ones in a sd-80 are medium in size in compared to those pittmans and the cheapies that Lionel uses in their starter sets that are small.
I guess the Nudge mode operation only works on the Cruise M board engine and not on the Lionel odyssey engine if you put those 2 engines together to run. I don't want to mention that L-up word so I don't cross over Rich Melvin's line!!!