The MT and RS4 RTR 3 both use 13t input gears and a 38t ring gears which is a 2.92 ratio. The big difference is the Evo has a tire diameter of around 2.5" while the MT is around 5". Thats why the gear ratios are so different. They do have 2 speed clutch bells for 2 speeds that were made for the MT. This was the part number that came with the 2 speed kit.

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