Calling all circuit racers..
It would help to know what type of racing we are talking about.( road racing, circle track )But from the setup, and the marks on the sway bar. I would have to say its to keep the rear end out of the fuel cell. Just look at the marks on it,and see how much the sway bar moves, the rear has hit it more than once. I'm sure it helps ty in the rear frame also.