i just picked up my 04 gt yesterday, and i just had 2 flowmaster 40s installed today, and ran them out to 3 1/2" tips. i had flows on my old 95, and my old 02, then on my hemi. ive always been a fan of the flowmaster sound. loud, aggressive and throaty, with a little gurgle as you down shift. as long as its a vintage muscle car note, then the louder the better, and ill be adding headers and an h pipe later on, but i needed some sound to get me by in the mean time.