At this point in the discussion we need some way of qualifying how much the changes affect the car's handling characteristics. Roll Couple Distribution (RCD) is a way of comparing setups. Example, to show which setup understeers more. RCD is simple the the dynamic weight in percentages of each end of the car. A higher percentage of change at an end of the car means that end is being loaded quicker and may slide first.

The theory is;

After making changes to a car, if the Roll Couple Distribution is unchanged. Then car will basically drive the same as it did before. Example: change all springs to be softer because of a rough track. Make the RCD the same and it will still turn in the same. Pretty Kool!

TransWt is short for Transferred Weight

Find Transferred Weight (Equation 7) in the Math section in the left menu;. Use it front and back and then use this formula.