The year was 1986 or so....car, was a Tamiya HOTSHOT, Option Parts from .....something from Japan, a center shaft with a DIFF.....I brought it cause it is an option.........does not make my HOTSHOT run faster or better, same as before.
I believed at 1 time I saw the exact same option (a shaft with a diff) for HPI Pro 4........forgot where, but of course, everyone knows that the 3rd diff does not work or serve no use....
This is belt driven, so i don't know is there any different then Shaft car....