i have seen the 8 3/4 mopars in big horsepower cars that hold up very, very well!!!!---i prefer the 9" because i have proved them on several violent reacting cars and have very little problems if any-plus i drive my cars on the street and strip and can change the pumpkin out for the street gears quickly---THE FACTORY WAR CASE AND NODULAR CASES WILL TAKE ALOT OF HORSEPOWER WHEN THE GEARS ARE SET UP RIGHT-[ I HAVE HAD MORE TROUBLE WITH THE U-JOINTS THEN ANYTHING ELSE]--BUT THEN I AM A FORD FREAK :lol: :lol: :lol: ---LIVELY