Originally Posted by Korey Harbke

They make it so the servo must travel further to give full steering throw. It increases resolution and makes the steering feel more precise and smoother. Similar to the way the tamiya knuckles effect our car, but these are designed specifically for our car and fit properly.

-Korey

Edit... I thought you meant the steering blocks and knuckles. The wider suspension blocks make the front end have a higher roll stiffness. Usually wider suspension blocks give you more initial turn in, and a little less steering through the middle and exit of the corner.