 |
|
 |
|
|
|
|
  KEEP M3POST ALIVE BY DOING YOUR TIRERACK SHOPPING FROM THIS BANNER LINK! |
|||||||||
Post Reply |
|
|
Thread Tools | Search this Thread |
| 02-17-2012, 11:58 AM | #1 |
|
New Member
4
Rep 29
Posts |
new wheel/tires - adjust speedometer?
My first purchase was to upgrade from the 18's to genuine OEM ZCP 19's. Do I need to make any adjustments after moving up in size (speedometer, etc.)? Does it depend more on tire size? My new tires are PSS XL - 245/35ZR on front, 265/35ZR on back.
|
| 02-17-2012, 02:44 PM | #2 |
|
Brigadier General
 
199
Rep 4,318
Posts |
Those are stock size, no need to adjust anything (not that you could adjust the speedo if you wanted to...)
__________________
GT3 RS | Desperately seeking the next great M car...
|
|
Appreciate
0
|
| 02-18-2012, 08:57 AM | #3 |
|
M3Post Supporting Vendor
87
Rep 964
Posts |
As long as the total diameter of the wheel and tire together is the same (it is in this case) nothing changes on the speedo. The speedometer is often off by several percent from the factory, so even if you have small changes in tire size most people don't worry about it.
Generally, a difference of 3% or less in rolling diameter is considered negligible.
__________________
_______________________________________________
I have accepted a new position at Tire Rack and am no longer in the sales department. gary@tirerack.com is available to assist with M3 questions. |
|
Appreciate
0
|
| 02-18-2012, 11:02 AM | #4 |
|
collecting toys
41
Rep 810
Posts |
If you have a smart phone with a GPS application, you can measure your true road speed vs the speedometer output while you are on the highway sometime.
Allows you to know the true offset. Stock wheels and tires often 4% high in speedometer reading in US for M3.
__________________
2011 e92 M3 Monte Carlo Blue ESS 535 - gone but not forgotten
2015 cayman GTS - new toy 2006 SLK 55 AMG sold  |
|
Appreciate
0
|
Post Reply |
| Bookmarks |
|
|
