this topic has already been made. i say raikage wins because he can match Gai's strength and best his speed in 8 gates. however raikage can use his fullpower however long he wants. gai can only use it for a short period of time. so raikage will outlast 8 gates gai and then kill him. furthermore chidori was only able to manage a weak wound against raikage's lightning armor. so i'd say gai's punches wont kill raikage. furthermore in 8 gates gai needs to end the battle quickly and that wont happen since raikage is faster than gai in 8 gates.