8 3/4 742 or 489 is good ! But to put real power to it in a pretty heavy car ! Have a friend with a dart with 451ci big block ! He could get a year on his 742 case no problem running 6:70 1/8 mile ! He started spraying it and it ran 5:70 1/8 mile. He started cracking the main caps on the carrier !! So if you going to being do that Dana 60 or a 9 inch !!
