Quote:
Originally Posted by Holander
Not, or do you have fact? There is car named Ferrari F40 and it have 50:50 weight distribution. But anyway only weight distribution not say anything, it depends so much were the weight is and are weight divided evenly on each corner/wheel.
|
The best fact I can provide is a technical explanation:
For an object to pivot around an axis, the total moment of inertia of that object needs to be accelerated around that axis. The moment of inertia is proportional to the mass times the square of the distance of where the mass is located relative to the reference point
I = m x d^2
If an object is pivoted around its center of gravity, then only the natural moment of inertia of that object needs to be considered. If the object is not pivoting around its center of gravity, the mass of the object times the square of the distance of the center of gravity relative to the pivoting axis needs to be added to the natural moment of inertia.
On the vast majority of cars, only the front wheels are steered. So when a car is turning in a corner, the car actually pivots around the middle of the rear axle (not considering tire slip angle) and not around its center of gravity. Therefore, the closer the center of gravity is to the rear axle, the easier it is to pivot the car; hence the better handling dynamics.
This is a major reason why mid engine cars are so nimble, first the natural moment of inertia of the car is lower because the mass is closer to the center of gravity and second because the center of gravity is closer the pivoting point between the rear axle.
However, it is also a reason why mid engine cars can snap oversteer and are difficult to bring back. While on oversteer, the pivoting point is now in the middle of the front axle (or somehere around it) with the CG way in the back thus increasing the total moment of inertia (think 911 for an extreme example here).
Other benefits of a rearward weight bias is increased traction on acceleration for RWD cars and a more balanced weight distribution on the tires when braking as the weight shifts forward.
BTW, I have always believed that the F40 weight distribution was more in the 60/40 range…
EDIT:
Found this: