Why do you use billet wheel spacers on your car?

Billet wheel spacers create a proper wheel fit and achieve a particular wheel appearance on vehicles such as hot rods. For safety reasons, automotive technicians generally recommend using spacers made of billet aluminum in sizes of 0.313 inch or less, with plenty of mounting surface.

Spacers that are made of pot metal or that are four-, five- and six-hole types that fit all wheels typically do not work well and may create vehicle safety problems. After mounting a spacer and a wheel on a car, an installer should make sure the right amount of thread engagement of the stud and lug nut is still available.