i need to be able to run with or at least close to m3 im thinking about a roush kit any better suggestions. right now stock but i need of major mods and ill be doing this by my self in a parking lot,and also the car see over 125 mph daily 05 gt

 

Well a BMW M3, from the ground up is a totally different car. It was designed to be the way it is, from the body to the engine to the suspension, etc.

You can make your cars suspension perform as well as the M3 suspension, but NEVER handle as well. By perform, I mean taking corners as quickly, alot of grip, etc. By handle, I mean driver feedback, steering response, driver confidence, balance... thats something that wont be duplicated with any mustang...

Items I'd look into are:

1. springs
2. adjustable shocks/struts (tokico d-spec)
3. Swaybars (eibach makes a great kit)
4. Panhard Bar/Control arms
5. Front control arm bushings

Sincerely,