Originally Posted by seapar

use the offset calculator see what how your potential wheels would differ in fitment with your current ones. you can see how your current ones "sit" within the arch and how much more you can tolerate if tire comes out more laterally by either different wheel/offset or spacers.

Originally Posted by dbman

I have a similar question. I am the second owner of a 2007 C4S and would like to buy a second set of wheels for the track.

According to my manual, my wheels are either:
8 J x 19 H2 front 57mm 235/35ZR19
11 J x 19 H2 back 51mm 305/30ZR19
or
8.5 J x 19 H2 front 55mm 235/35ZR19
11.5 J x 19 H2 back 67mm 305/30ZR19

The stamps on the OEM wheels say "8 57" front and "11 51" rear, which matches the first specs. Would the wider (8.5" and 11.5") wheels support the same size tires better, thus improving handling? Is there any advantage to the narrower wheels?

I assume it's best not to mix 8" fronts with 11.5" rears or 8.5" fronts with 11" rears?

Thanks, dave

Originally Posted by frontside720

I'm interested to know as well. I'm looking at a set of wheels for 2006 C4S but they are 19 x 8.5" Front And 19 x 11 Rear is it o.k. to not follow the 8/11 or 8.5/11.5 rule?

Thanks

( ^ WHEELS LOOK GREAT BTW ^ )

Originally Posted by jhbrennan

8.5 and 11.0 widths will work just fine but you have to make sure you have the correct offsets.
OEM widths on the 997.1 turbo (widebody like the C4) are 8.5 front and 11.0 rear.

Originally Posted by p's pcar

So can you take 997.1 turbo wheels and put them on a 997.1 C2S without any problems? Looks like it will bring the wheels out 7and 16 mm according to the wheel calculator. Thanks.