Originally Posted by
Greg Amy
They're an "nth degree" thing on the scale of all the stuff you want to do. Springs/shocks/swaybars are all more important. Sphericals' primary function is to reduce the flex and movement (to improve geometry) and to reduce "sticktion" so your shocks and springs are more repeatable and consistent. In some limited case (e.g., Nissan 240SX) they allow a larger range of unbound movement, but for most cars that's not such a big deal.
Sphericals "can" make a big difference, but IMO only once you've taken care of all the big stuff first.
GA