The Speedway arm are for round track cars, and the drivers side upper arm is longer to change the "pitch" of the wheel.406Monte said:What is the reason that some of you are running two upper right side upper arms and not one of each.. I am wanting to do with upper and lowers but am undecided on them. Now, I am rading that some of you are running two rights and now I am confused. I need some clarification on this. I am using my car 90% track and 10% street if that hlps any also. :-k