So I'm thinking of buying these to lower my car, i do have the performance pack on my v-6 so im not sure if this will be a upgrade or downgrade. Please feel free to throw some wisdom my way. Also, will i be needing anything else?

http://www.americanmuscle.com/sr-springs-0513gt.html

 

mach951,

The SR springs will definitely be an upgrade over any stock set up. Installing a set of SR Performance Progressive Rate Springs will lower your Mustang's center of gravity, which will reduce squat during acceleration, body roll in the corners, and excessive nose-dive under hard braking. These are great for daily driving, street, and even occasional track use.

This is just my opinion. Let me know if I can be of any assistance!

-Dan