OK, car is an '02 C4S with what I believe are stock turbo-twist wheels, but I'm not the orignal owner so can't be sure. So anyway I'm replacing the rear pads today and got to looking at the wheels from the back. The spokes have deep grooves in the back, presumably to reduce the wieght.

Does this mean they're the "hollow" spoke wheels?

 

Screw in valve stems, but the only holows on c4s cars were the sport technos, all the rest are solid. The grooves you describe are a trademark of solids I believe.

 

Two ways to tell, (1) Metal valve stem = hollow spoke, rubber = solid (2). Grab the spokes, if you feel ribs in the back of the spokes then it is solid, if feel smooth then it is hollow spoke.

 

With hollow spoke the back of the spokes are smooth. Groves means solid spokes.

 

All the above. Plus, the C4S comes standard with the solid spokes.

 

OK, pretty definitve answers - I've got solid spokes.

Thanks!

 

Ribs in the back. Solids here too

 

hollows... bend easily, be happy you have solids!

 

...uh, I don't think so. I have a set of both; the solids(for winter use) that came with the car and a set of hollows (for summer) bought off a 996 TT. My rear solids have bent, but not the hollows.

 

Anyone know the weight difference between solids and hollows?

 

996tt mostly use hollows... however the 996gt2 use solids.... they are stronger and heavier! In NY/NJ area winter is def harsher than driving in the summer.

 

The 2001 996 TT came with solids.

Factory 996 Turbo Hollows
8x18" at 22 lbs 2oz
11x18" at 26 lbs 5 oz

Factory 996 Turbo Solids
8x18" at 26 lbs 2 oz
11x18" at 31 lbs 6 oz

Factory 996 GT2 wheels (earlier years, Turbo Solids):
8.5x18" at 28lbs 11 oz
12x18" at 33 lbs 0 oz

Factory 996 GT2 wheels (later years, GT3 style)
8.5x18" 25 lbs 2 oz
12x18" 29 lbs 0 oz

and for some comparison

Factory 996 GT3 wheels
8x18" 22 lbs 10 oz
11x18" 27 lbs 11 oz

Factory Carrera S 997
8.0 x 19 - 22 lbs. 4 oz.
11.0 x 19 - 27 lbs. 12 oz.

 

http://www.944racing.de/reload.php?u...elweights.html

Good site w/part numbers.