In addition to its size (which is a big one).
- Integrated aluminum bell housing (No scattershield)
- Double overdrive (5th and 6th gears. Camaro/Mustang .8? & .6? or Viper .7? & .5? options. You'd be better off with a 5 speed with 1 overdrive. Late model cars with computers and efi can live down low much more efficiently than carb'd cars)
- They are only rated at 350 ft/lbs (Viper one is rated at 450)