well the 03 z06 (both cars bone stock) is a hare faster around the track because of the little better tires that gm puts on them. but from my opnion i would have to say you really can feel the g's better in the 03 z06. but my dads 05 is probly faster because he has long tube headers x pype and a corsa exaust as well as a ram air intake. the z06 is stock excecpt for a diablo tune.
ohh and as for your amd that sounds rite