[ausgeflippt951]

As others have said, it asymmetrically biases a bit more spring rate to one side of the car.

I'm typically not a fan of preload, as there are often more effective means of achieving the same results, and too much preload can really mess with the car's transitional capabilities.

The only exceptions I can think of, in recent history, are at MidO and Lime Rock. The types of corners in one direction are distinctly different than those in the other direction, so we played with preload as a means of fine tuning the spring rates. At Lime Roc, however, I also ran different springs L-R.