I just finished the first round of mods to my 99 GTP and i am crazy happy!!!
started with a stock GTP for $500. New HD tranny, some new 18" katana's and 40th anni stuff i found at the pick n pull.
Drove it like that for a min than added speed daddy headers and gutted the stock air box. In just the last two weeks i started to mod... =o)
Installed 1.9 rockers, 90# springs, NGK tr6 plugs, 180* stat, zzp PCM, 3.4" pulley, a full zzp lowering spring/stut kit, 20010 impala duel piston break calipers and 11.9" rotors.
My car is soooo much more fun to drive now! The next thing i want to do is add a W body or zzp intercooler and drop to a 3.2 pulley. Man o man, i can't wait!!!