Hello, I own a 99 Crown Vic and beefing up the suspension was the first place I started. Get rid of that girly .67 inch rear sway bar, and put in an Addco 1 incher. You'll notice a significant improvement in high speed cornering, and use the Energy Suspension poly bushings, I recommend swapping out the stock zinc coated hardware and using stainless steel fasteners. 3/8" bolt, etc. Next look at steel or aluminum rear control arms to replace those adequate, but mushy rear bars. Look at adtr.net. | 
