The LR trailing arm has a significant effect on rear steer associated with excess squatting on acceleration. If the car squats on exit, that motion can be utilized to promote rear steer and increased forward bite. It can also cause the car to be loose. With the arm uphill (front higher), the left rear will move back, providing rear steer to the left and making the car tighter. If it starts out level, the squatting motion brings the left-rear wheel forward, causing rear steer to the right and making the car loose.