To me the toughest part about weight is inertia. Sitting at a dead stop and accelerating hard is where weight challenges motion the greatest. While true with the aid of good gears, converter, or massive amount of torque can mask this effort to look effortless, science facts aren't changed. Thinking on my Duster, or any vehicle for that matter, a motor can seem bigger with nothing changed except weight loss. A 120 hp is enough to go 10's if it's in a light motorcycle. The only reason cars are faster from 0-60 than they are from 60-120 is simply because of gearing, and maybe some wind resistance. It's why machines with variable drive clutching will simply not take off if the clutches are messed up and the belt is all the way at the bottom of the driven pulley, but once moving will gain speed with them in the same position. Inertia.
