Forza mods

forza 4-6 unlimited money,and any car free,insane speed

Is that a question or a statement?
Forza 5 and Forza 6 are XBONE games, so at the time of this writing, no exploits exist.
As for Forza 4, Yes.You can mod Credits, LvL, and XP, Unlock Liveries and Paints, Max out Affinities, and add Unicorn Cars.