From Bob's site....
03/04' WEIGHT REDUCTION
Spare tire...................................-26.4 lbs
Jack/crow bar..............................-6.6 lbs
Trunk pad...................................-6.0 lbs!
Mott bar (under diff).....................-7.8 lbs
Front sway bar/brackets................-12.4 lbs
Rear seat bottom.........................-11.0 lbs
Rear seat back.............................-25.6 lbs
Rear seat head rest.......................-5.6 lbs
High flow catted midpipe................-22.6 lbs! (stocker=36.0, High flow=13.4)
Odyssey battery/bracket................-22.2 lbs (stocker=37.6, Odyssey=15.4)
Front 3.5" ProStars w/ ET Fronts......-49.6 lbs (stock chrome w/ F1's=49.8, Skinnies/spacers=25.0 each)
Rear Diamond R 16" w/ ET Streets...-10.8 lbs (stock chrome w/ F1's=49.8, Diamond Racing Wheels/ET Streets=44.4 each)
UPR K member kit.........................-65.0 lbs
Front Passenger Seat.....................-43.0 lbs
Total Reduction....................... - 314.6 lbs.
To further reduce the amount of weight on the Cobra, the following items may be removed:
Rear seatbelts: 5 lbs
Supercharger pulley guard: 2.0lbs
Mach460 head unit: 5 lbs
Mach460 rear enclosure w/amps: 22 lbs
Mach460 front speakers: 5 lbs
Front driver seat: 62 lbs (replace with lightweight seat)
Front passenger seat: 43 lbs (replace with lightweight seat or just delete)
Lighter wheels: (maybe 25 lbs. for the street and 70 lbs. for the track)