 Only peasants drive around in cars with stock wheels. So, today's Cobb CQC is all about wheel specs and measurements, so you can turn your car into a king's carriage. Try to remember some of the basics of CQC. Here are the key details to research when shopping for wheels. The first is bolt pattern. Knowing the bolt pattern tells you if these holes line up to these studs, or they'll be bolt holes if it's a German car on the hub. And if these don't match these, then you can just stop right there. If you don't know, it's easy to measure. For four or six lug wheels, you simply measure the distance between the center of one stud to the center of the stud across from it in millimeters. And for five lug, you measure from the center of one to the back side of the stud across from it. The total number of studs, along with the measurement, equals your bolt pattern. This is center bore. Usually your hub will have a small circular lip, and ideally the outer diameter of that lip will match the inner diameter of this hole or center bore on your fancy new wheels. Naturally, if the center bore is too small, then you can't even put it on the car. But if it's too large, no worries, you can usually find a hub-centric ring that's designed specifically to fill in that gap. Those two specifications will determine if you can even mount the wheel on the car. Then you can move on to determining fitment and clearance. Starting with knowing the wheel width and center line. To check the width, you do not measure from the outside edges. You measure from the bead seat for the tire just inside of the lip to the other bead seat. So this is a nine and a half inch wide wheel. Once you confirm that, then measure halfway or 4.75 inches in this case from one side and then boom, that's your center line. Knowing your center line is really important for understanding offset and backspacing. And lots of people tend to misunderstand or interchange those terms but they are different from each other and they're important for different reasons. Offset is simply the measurement, usually in millimeters, of the relative distance between the wheel's center line and the mating surface in the middle of the wheel that contacts the hub on the car. If they line up perfectly, the offset is zero. If the hub mating surface is closer to the inner lip of the wheel, the offset is negative. And if it's closer to the outer lip, then the offset is positive. The most obvious difference you'll notice with various offsets is how it affects the look and shape of the wheel face regarding how flat, convex, or concave it appears. But it can also play a significant role in the vehicle's handling and driver feedback when changed by large amounts, so it's not only about style. Backspacing is all about fitment or more specifically about clearance on the back part of the wheel. Backspacing is the distance between the hub mating surface on the inner lip of the wheel, which lets you know how far the wheel goes inward once mounted, which could potentially make contact with things like suspension parts. It's not the same thing as offset, but the combination of the wheel's width and offset will determine the backspacing. And luckily, there's a helpful chart that does the math for you. If backspacing becomes an issue, then using a wheel spacer is an effective and safe remedy as long as you do it correctly. Wheel spacers are their own topic that I'm not really going to go into, but just keep in mind that any time you use a wheel spacer, it is going to change your offset and your backspacing. Lastly, diameter. Most people just assume that the measurement of diameter is from the outer edge of the lip across to the other. But that's not correct. That would be too large. It can be difficult on some wheels to find a clear visual reference, but similar to width, the accurate point of measurement is from the spot of the tire bead seat to the other. And for choosing the appropriate size, that's ultimately up to your priorities. Are you trying to be a hot boy with that flush lip tuck for style? Or do you want a functional setup that maximizes handling weight and grip with the ideal performance tire? As long as the other measurements work out, it will make you happy. Or at least what you can afford. Plus, a lot of the measurements that I talked about are actually stamped right on the inside of the wheel. So you can always double check that when shopping second hand to be sure you're getting exactly what you need. Coptuning has teamed up with Titan 7 to produce a fine collection of forged wheels for specific Subaru and F-150 models where we did the hard work of getting perfect fitment so that you can just purchase them and slap them right on your ride. But that doesn't mean that they won't fit on other cars as well. And now that we've bestowed upon you our royal knowledge of wheel specifications, you can confidently barter for any wheel to put on any car of your choice. But you should just buy these.