pumpedTSI

Posted this on the S55 forum but not much action over there...........
Im about to fit some 19" wheels on my S55 and wondered what size tires can I go with that wont affect speedo or tranny input ratios and set off any warning lights?
The wheels are 8.5" front and 9.5" rear. I want the widest tire I can run front/back but DONT want the ultra low profile type 35 series......am I making sense?

babyboigsxr

Try this...

http://www.1010tires.com/Tools/Tire-Size-Calculator

Enter your current OEM tire specs.
Then enter different sizes you'd like to use.
There's a percentage bar to give you a pretty accurate idea for change in speed.

Dublinoh

If you go wider but don't go to a smaller aspect ratio (like 35) you will have a bigger circumference tire and you will affect the speedometer.

Dublinoh

So if you go tirerack the stock size for your car's rear is 265 40 18. If you go to a 19 inch rim they suggest a 275 35 19 size. You said you wanted the profile to be greater than 35. The next size is 275 40 19 which is the same width as the suggested tire but will make your speedometer read approximately 5% slow. You need a 35 profile with 19 inch rims or a narrower tire than recommended.

HeissRod

No way to upsize to 19s and keep the speedo correct, without going to a 35 series tire.....unless you were to run a 235/40_19, which would look ridiculous and end up being the same sidewall height anyways.

pumpedTSI

Thanks guys.....got it!

ap10046

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