INANE

I've spent a few weeks now researching what would be involved in replacing my 97's OEM sized wheels. I'm looking to go to 18/19. What's driving me nuts is finding wheels I like with the correct size/offset.

To that end I think/hope I've narrowed it way down.

For the rear I'm looking at wheels that are 19x10 with an offset of 56

For the front it's between:

18x9.5 with an offset of 50 or 18x8.5 with an offset of 56.

I'd really prefer the 18x9.5 but when I use this calculator it says the 50mm offset would cause the wheels to extend 19mm over OEM. That just seems like a little much but that's one reason I'm here, to ask what others think. The new rear 19x10 would just extend an additional 7mm which seems reasonable.

I have some tire questions as well but I think some of that will depend on which wheels I end up getting. Thanks for any feedback.

INANE

OK, so moving on. If I decide to just go with the 18x8.5 front rim:

Front 18x8.5
255/40-18 = By my calc is 1.36% larger diameter than OEM (26.03inch) (OEM = 25.68inch)

Rear 19x10
285/35-19 = By my calc is 0.72% larger diameter than OEM (26.85inch) (OEM = 26.66inch)

To my eyes that means my front to rear difference would only be 0.64% off from OEM.

I asked Tire Rack about this, they thought that would be a problem. They either wanted me to change the front to a 265/35-18 (2.19% total difference) or the rear to 295/35-19 (0.40% total difference):
What am I missing here. At this point I'm more interested in understanding this all than anything else. I know you can look at it from just an inches perspective but wouldn't a percentages perspective be the same?

VETFEVER

Lots of people here have used TSW wheels on their C5 and C6's. They are well-priced, well-made and have perfect offsets for these cars.

Do a search in the general C5 or C6 sections using TSW and you will get many hits with examples of TSW wheels.

The have done the fitment math for you...