There are only four factors that affect the amount of weight transferred:
* The total weight of the vehicle--more weight means more weight transfer, all else being equal
* The force acting on the center of gravity--more force means more weight transfer
* The height of the center of gravity aboveground--higher centers of gravity transfer more weight
* The track width (for cornering) or the wheelbase (for acceleration and braking)--narrower track widths or shorter wheelbases mean more weight transfer
Nothing Else Affects the Amount of Weight TransferLet's look closer at each of these factors. We have already discussed total weight. Since we want to run as light as possible--or at minimum weight--this is a constant factor that we cannot change unless we are over the weight limit. The traction force of the tires determines the force acting at the center of gravity. Reducing the traction or driving below the limits of tire traction are certainly contrary to our goal of getting around the track as fast as possible, so this is not really a factor.
Illustrations 5 & 6: These...
Illustrations 5 & 6: These illustrations compare a car at rest to the same car in a corner. Weight moves to the outside.
Maximum track width is always set by rules, and unless you are running at very high speeds where aerodynamic drag is a big factor, you want to run the widest track width possible, so again, this is not a controllable factor. But the center of gravity, the point within the car where it, if suspended at that point, would be in perfect balance, can be altered. Maybe it can't be changed much on some cars, but enough to affect performance. Simply keeping weight as low as possible in the car will lower the center of gravity, thus reducing weight transfer. This is extremely important to consider when building a car or adding a ballast to the chassis.
There are many misconceptions about weight transfer. Only the four items listed affect the amount of weight transfer. Body roll has a very minimal effect and should not be considered a factor. Dive and squat are not factors, and neither is the phase of the moon. So, do not be misled to believe that anything other than those four factors have an effect on the amount of weight transferred while cornering, braking, or accelerating (Illustrations 5 & 6).
The Driver
Often overlooked as a race car dynamics factor, the driver is actually a major factor. The driver controls when dynamic events occur based on when he uses one or more of the controls. The driver determines--at least in part--how quickly dynamic events occur based on how fast he uses the controls. Many drivers are too abrupt with control inputs and upset the dynamic balance of the chassis, which degrades overall vehicle performance.
The Overall Goal
It is important to keep in mind that the singular goal is to get around the racetrack as fast as possible, whether for a single lap or an entire race. Race car dynamics relate ultimately to tire traction at the tire contact patch. Optimizing traction on the complete car means faster lap times. We can do this by manipulating the chassis components and the driver's steering, braking, and accelerator inputs. The team doing the best job of this will be in the top five. From there, tactics, strategy, execution, and maybe a little luck will determine the winner.