there are alot of Mercury Grand Marquis
" MARAUDER " models running around with some impressive tweaks AND SUPERCHARGER by Trilogy
. Maybe they have some stuff that will work on the Crown Vics too. These cars are sleepers and run strong , see :
http://www.trilogymotorsports.com/products/index.php
laugh if ya will, but if ya want a big boat that can surprise some folks, this would do it . Bill.