Shmurzik

I am about to buy replacement rear tires for my S4. I usually use tirerack.com – and their automated tire selection feature specified tire size as 245/45-16 yet I seem to remember that the tires currently mounted are 245/50-16. Question: who’s right (PO or tirerack) and will this make any difference? Thank you, all.

GlenL

tirerack

Bigger tires are, umm, bigger and will make your speedo read low.

shaaark89

245/45/16 is the stock recommended size for the s4 rear. if you use a 245/50 it will change the rollling diameter from 24.68" to 25.64" which will make a 3.9% difference in the registered speed on the speedo (it will read low). otherwise may not notice any difference in the handling or way it drives.

Jim bailey - 928 International

the 245 x45 has a sidewall height of about 110 mm the 245x50 has a sidewall of 122.5 mm ........so the extra 1/2 inch or so of rubber between the rim and the road "looks" funny makes the car look like a drag racer with "bigs and littles" with the rear up in the air . Get the correct size tires 245x45 .......for the 8 inch rims .

mark kibort

you can safely go to the 255x45 16 tire, as i was able to do the 245x50x6 on a 7" rim, so the rear S4 rim of 8" will fit that larger tire fine. on my 84, on the old 7" pan rims, it looked very good. no dragster look there. it nicely fit the fat old 928 rear end much better than the stock 225x50s and certainly better than the even larger 245x45s on the 8" S4 rims.

we commonly put a 275x40 on a 9" 18 or 17" rim, so a 255x45 is not a stretch for a 8" rim. the bmw guys do this often.

mk

Gregg K

Mark,
Where does one find 255x45 16 tires? I'm looking for them, but they don't sell them at the Tirerack.

By the way, what year did you graduate from Cal Poly. 1990, here. M.E.

Shmurzik

two 245/45-16 tires coming right up! thank you, all