we still dont know the full extent of the 8 tails power thou it cant be greater then the 9 tails but if the chakara protects him like it protects naruto it would be hard for piccolo
they have trouble beating giant apes now what about a giant ox?
listen DBZ chaters powers are inconsisten one minute they are monsterously strong and the next they seem to have down graded
i think the 8 tails would win because he has full control of his bijuu