PILLOWBALL VS RUBBER TOP MOUNT
PILLOWBALL TOP MOUNT
Pillow ball mounts are solid metal mounts that are used in areas such as the upper strut mount. The rubber normally used is replaced with a metal spherical bearing. Rather than deflecting from the cornering forces like a conventional rubber bushing, pillow ball mounts do not move at all. This translates into a far more precise feel from the suspension and steering.
Pillowball upper mounts are designed for coilover system and improve responsiveness for any application. These mounts replace the stock rubber or plastic mounts to reduce flex and improve performance. The angle of the contact patch of the tire is changed improving handling when installed on the coilover. Camber can be adjusted by the pillowball top mount on McPherson applications only. Pillowball top mount also give your car a wider suspension tuning capabilities for on the road use and also track racing use.
RUBBER TOP MOUNT
Almost all cars use rubber bushings in the suspension. The reason for this is that rubber bushings absorb much of the force produced by the vehicle's suspension when it is driven over bumps and road imperfections. This in turn isolates the occupants and provides a more comfortable, compliant ride. One of the issues with rubber bushings though is that, because they deflect more, the suspension can lose precision. This is generally not a problem for normal driving, but if a car is modified for better handling, a more rigid setup may be desired. Among the solutions to make a suspension more precise are urethane bushings as well as a more extreme solution, which are pillow ball mounts. In other words, rubber top mount is more practical to use for one the road because it is so much less noise and comfortable as it absorbs better.