Originally Posted by wstar

The best bang-for-the-buck weight mod is definitely light wheels/tires, and there's no real "tradeoff" there, it's all win. Going right along with that would be lightweight (2pc) brake rotors, but they're a little pricey for what you get, and probably mostly only worth it on the front pair. Light seats are obvious. Pricey, but also hold you in better.

A good cheap one for dropping front weight is to ditch the whole windshield-washer-sprayer system. Or you could just empty out the tank completely dry to get most of the same benefit without permanently removing anything.

You can drop a pretty decent chunk of static weight from the car by doing the combo of emptying out the trunk (subwoofer, spare, foam, plastics, etc), removing the big heavy battery up front, and relocating to a smaller battery like the PC680 mounted in the newly-empty trunk area. I list this as one big combo-upgrade, because if you just empty out the trunk and don't do the battery work as well, you're shifting the car's weight balance in the "bad" direction.

If you do both, the weight balance is basically unaffected (if anything, it goes barely in the "good" direction), and you get a significant net weight drop. Going off an estimate from one of my own old posts, you'd get just under 70lbs of weight drop from this, with a slight bias towards front weight drop.

(EDIT: the old numbers I came up with were 35 from the front and 29 from the rear, but that didn't include plastics/foam/etc from the trunk, just the big ticket items: spare, subwoofer, and battery swap)