I dont think the wheels make a difference. I was going 70 on the highway the other day. GPS says 70, but SPEEDO said 75. So it is about 5 MPH off. If you do a search you will find alot of info on this.
2015 335xi | Mineral Grey Metallic | Black Dakota Leather | NAV | SportLine | ZPP | ZDA | ZCW | Munich Build
Retired: 2008, 2011, 2013 328xi