1. Get some lightweight aftermarket wheels. You have the most common bolt pattern for any older car, 5x4.75 inches. A used set of Weld or Centerline wheels will save you probably at least 10 pounds of rotational mass per wheel.
2. Electric fan. Lose the factory clutch fan. Electric fuel pump will help too.
3. Lower it. All G-Bodys look better lowered a bit anyway lol.
4. If you want to spend more money, then an aluminum driveshaft, aluminum radiator, and aluminum intake manifold.
5. Pull the carpet, and take out all the sound deadener, then replace the carpet. That stuff is heavy, especially is the inside of the car has ever gotten wet, it soaks up water and holds it.
6. If the vehicle was not going to be used on a public road *cough cough*, I will say that the hydraulic struts that the bumpers attach to are really heavy, they compress in an accident. I have heard that people remove them and replace them with a simple piece of aluminum or steel. Said people have also been know to cut the steel crash bars out from behind the bumpers (which are already steel), and some even the impact beams out of the doors. They are 20 or so pounds a piece. Apparently. But such actions are obviously irresponsible!!
