[mustangII460]

The insulators are basically a cheap way to lift the front end up without a taller spring. With 1/4 inch your providing basic protection between two parts, without adding height. The higher your car is the higher the center of gravity is, not good.

I would call and tell them what you want in performance. There are alot of different types of springs and combos. Factor in a sway bars too.

I like a progressive rate spring with heavy sway bars. So striaght line is not harsh, but I can turn hard with minimal body roll. This is the best of both worlds, drag and turning performance.