Originally Posted by MKE_M3
First, the car would be 333lbs heavier if the engine wasn't lighter (using your numbers). Lighter is better.
Second, Acceleration is a function of power (to the wheels), weight and traction. Although the engine has little effect on traction (smooth power delivery helps, but both engines have that in spades), but all else equal, more power and lighter is better.
If you can add power and save weight, that is good, so why wouldn't people be excited about BMW's new (six years ago) engine being significantly more powerful 414 vs 333, and also lighter?
i think his point was the lighter engine isnt helpful if the car weighs more anyway. the goal should have been the entire car being lighter. only advantage is possibly to allow a better front to rear weight distribution because the engine load is carried on the front axle.