BMW WHEEL REFERENCE GUIDE
BMW Wheel Size Compatibility Guide
Two wheels described as the same diameter are not necessarily interchangeable. Compatibility is a vehicle-specific conclusion, not a single-number lookup.
1. Build the current setup
Record the existing wheel width, diameter and ET plus the complete tire size. Note front and rear separately when the car is staggered.
2. Compare the proposed geometry
Estimate inner position, outer position, overall tire diameter, circumference, ride-height change, and speedometer difference.
3. Verify what calculations cannot
Confirm the chassis, brake package, hub interface, hardware, tire load and speed ratings, body clearance, suspension clearance, and local requirements before buying.