What Size Should I Use?
Knowing why you need spacers leads you to the question of what size to use. The best way of figuring this out is to measure the gap between your tire and the inside lip of your fender. This will tell you how much space you have before the tire will make contact with the fender. Too big of a spacer will obviously give you rubbing issues.
So the answer is - How much space do you have to work with? Measuring your wheel gap is very easy and we have provided some examples below. Turner Motorsport may be the biggest BMW wheel spacer dealer
in the world. As such we have learned not to make assumptions on spacer size. Every situation is different and the best advice we can give is to
measure your car. It's tempting to listen to what everyone else is running but unless they have your exact wheel, exact tire, exact suspension, and exact suspension settings, no one can tell you what spacer size to use. They can only guess... Please keep in mind that spacers that have been installed and tested cannot be returned. This is to be fair to the next customer who expects new, top quality parts from us. Which is all the more reason to be precise about what size you can install.
Here are some easy ways to measure your wheel gap --
Old-Fashioned Tape Measure
With the car on the ground, hang a piece of masking tape from your fender. Stick a quarter or a nickel on the end so that it hangs straight down. Next measure in from the masking tape to the outside edge of your tire. This will tell you how much space you have until the tire would contact the lip of the fender. Pick a spacer that is slightly less than this measurement. This will ensure the tire does not rub on the fender lip.
Even More Old-Fashioned Rulers
Same as the method above but if you don't have masking tape to hang from the fender, you can use a straight-edge or ruler and another ruler or tape measure. Gently hold the straight-edge from the bottom of the fender lip. Measure in to the outiside of the tire. The gap between the straight-edge and the tire is your available clearance. Choose a spacer size slightly less than this dimension.
Wheel Studs and Washers
For this method, you would purchase at least two wheel studs to thread into the hub and corresponding nuts to lock the wheel down (
link to TMS 90mm studs). Remove your wheel and bolts. Thread the studs into the hub. Place washers down the stud to the hub. Slide the wheel over the studs. If it makes contact with the caliper or suspension, add more washers. Once the clearances are set, lock the wheel down with the nuts. Lower the car to the ground and roll - don't drive! - the car back and forth so the suspension will settle. Check your clearances again and also for tire-fender contact. Adjust if necessary. The end thickness of your washers will be your minimum spacer size. If you have space left over before the tire hits the fender, consider going with an even bigger spacer for improved looks.
Remember to remove your studs or install them the proper way before driving.
Studs and washers installed in the hub. Pictured is a BBS 90mm stud and 5 washers (roughly 15mm).
Studs and washers installed with the wheel.
BMW Wheel Pin and Washers
If wheel studs are not available to you, you can use the factory BMW wheel pin tool in your tool kit. More than one pin is recommended. This method does not allow you to set the car on the ground as the wheel pin will not support the weight of the car and there is no way to fasten the wheel to the hub. Don't even try it! Remove your wheel from the car. Insert the pins into the hub. Slide M12 sized washers onto the pin down to the hub. Slide your wheel onto the pins until it contacts the caliper, suspension, etc.. Add washers until the wheel sufficiently clears. The thickness of your stack of washers is the size of your spacer.
Factory BMW wheel pin tool installed with washers.
OK, so now you know what will likely fit. Choose a spacer slightly less than the maximum gap. Remember to order longer wheel bolts too!
Of course, that's not the whole story so read on for a more in-depth look at spacers in general, as well as some helpful tech info on fitments.