the cobra's have thicker vented rotors with thinner pads/same calipers. the cobra's all came with 3.27:1 gearing. i'm not sure what gears the 94-98gt's came with but the 99up gt's i think come with 3.27 and the 93 5spd had the 3.08 option. i think all the auto's came with 3.27.
-steve