what is the car being used for? If you aren't frag racing dropping the hammer at 6k the 8.75 will be fine. If it makes you feel safer back brace it. Looks like a road racing car, a dana adds weight. My old 440-6 Charger went 11.20's @ 121+ had a 8.75 and 3.91's no issues at all. That was much more than 450...not too mention the added torque of a 440.