This assumes you are focusing on or original Xbox modding , as XISO is the standard disc image format for the original Xbox.
(expected May 2026), meaning no further major feature updates or new cars are planned for the 2023 title. how to convert forza motorsport xiso updated
Often considered the series' peak, updated XISOs for FM4 focus on enabling all DLC cars and tracks which are otherwise inaccessible. This assumes you are focusing on or original