From my own experiences i learned that measuring corneringweights for an rc car doesn't work.
Every time i lift the car and place it back i get different readings from the scales. It's almost impossible to balance the car. And when you have the car close to a good balance and then check it with the normal tweak method or tweak board, it;s not even close to a balance.
And before you start tweaking a car by using scales you have to balance the chassis on a set of pins, and make sure you are using matched springs.