Thats the fun of dirt racing. Deciding what will make those four little rubber contact patches work better.
Its not always cut and dry.
Knowing when to increase/decrease load on a particular corner is the hard part.
Why is one or more corners of the car not working? Is the load on that tire too much or not enough? Is the spring too stiff thus shearing the contact patch? Is the tire too soft or too hard?
Deciding on whether a tire needs more or less load for a particular track condition is the trickiest part.