These arms, if employed, are preferably arranged spirally on the surface of the drum. In order to secure proper atomization with an arrangement of this sort, the drum must be driven at considerably higher speed than would be required for a brushing member provided with closely spaced bristles....
I do not recommend installing the UUC bushings unless you were going to race the car. It also results in a pretty severe driveline boom when changing gears. I will be returning the car to the factory bushings as soon as possible. Unfortunately I made the mistake of throwing the old ones ...