When I went to 4 1/2" pattern I used a adapter. Never had a problem with them on the front. It does as mentioned above, it out sets your wheel the thickness of the adapter. I'm running the adapters on my 67 Barracuda in my picture. I later found a 74 Dart disc brake set up and converted it. The car came with a 8 3/4 and bought aftermarket axles for the rear.