Ok, well I bought some 17x 7.5 et 35 wheels (used) they came with some hub centric rings but they dont fit the 97" C230, I would like to know what size do I need for the inner of the ring for it to fit on the mercedes? I know that the outside is 72.2 which fits the wheels itself but the inside is 57.1 which doesnt fit the car itself(to small).
Anybody know what size I would need?

Also the original studs for the wheels I was told are to short and that I need to get extended studs for the car. Anybody know what size I would need the extended studs to be???
Thanks,

The Mercedes hub is 66.56mm. So, look for a ring with 66.56 inside and 72.2 outside. To determine the lugbolt needed:

1. Put the OEM lugbolt through the OEM wheel and measure how much thread sticks out the back. One inch = 25.4mm (example: 18mm)

2. Put the aftermarket lugbolt through the aftermarket wheel, measure how much thread sticks out the back. (example 13mm)

3. Since the aftermarket lugbolts are too short, subtract the measurement from step 2 from the measurement in step 1. (18-13mm = 5mm)

4. Add that difference to the known length of the aftermarket lugbolt (example 23mm aftermarket bolt + 5mm = need 28mm lugbolts).

The lugbolt length is a measure of the threaded portion starting at the bottom of the head (conical head I assume?)

On a side note, my black 18" HRE wheels for sale would be a direct fit.

Follow the link to the Classifieds posting:

https://mbworld.org/forums/wheels-tires/259311-fs-18-hre-446r-w-pirelli-nero-s-c-clk-slk.html

I will be glad to contact HRE and confirm fitment for your car (including lugbolts) if you're interested.