Some specs I have from my digital bathroom scale:

17" Volk CE28N with Kumho Victoracers:
Front - 36.0 lbs (225/45/17)
Rear - 37.5 lbs (255/40/17)

Stock '03 wheel with stock S02:
Front - 39.0 lbs
Rear - 41.5 lbs

Stock '04 wheel with stock '04 RE050:
Front - 40.0 lbs
Rear 48.0 lbs

Keep in mind that the Kumhos rears are down to slicks, and the S02s are 1/2 to 3/4 worn. Even so, that's a huge weight difference with the '04 rears.

(I weighed both left and right sides and the readings were identical, so the scale is perfectly consistent.)

Has anybody else tried this?