There's better stuff out there such as Caltracs but with me being on a budget on my old Duster I took Monty Smith's advice and added one leaf to the bone stock leaf springs I had, which strengthened the front segment of the springs. I used Rancho 5way shocks and a 275/60/15 drag radial. I was able to drive the car to the track with 3.23 highway gears, run 10.60's-10.70's and drive it home. It never spun the tires.