I am now leaning towards getting another Crown Vic. (Sport model) because there is little to nothing you can do to the LS.

I know some of the mods you can do to the 4.6's but go ahead and list off the ones that are most effective for the money. Keep in mind this will be a new car so I can not do any crazy shit like a blower that will kill the warranty.

Feel free to list off more than one.