Fit Late-Model Wheels on a Vintage Mustang

Made from 6061 billet aluminum, the NPD adapters include 20 new lug nuts, longer studs for the rear axles, and 10 standard lug nuts to install the front adapters on the existing front studs.

The Baer brakes and 12-inch front rotors on our car have replacement studs in the wheel hubs. This can be an issue for some wheels as we'll discuss in steps 4 and 5.

1 Whatever studs are on your car, the front 1-inch spacers slip right over the car's existing wheel studs.

2 Thread the supplied standard lug nuts in place to secure the spacer on the hub ...

3 ... and tighten securely with a ratchet and socket. Tighten as if you were installing the wheels on the car. A torque wrench is a good idea, as these lug nuts should be tightened to 70-80 lb-ft. Have someone hold the brake pedal to securely tighten the adapter. The wheel then installs right onto the adapter as normal.

4 If your car has the original wheel studs that are threaded all the way to the outside end of the stud, then this issue isn't likely to be a problem. However, if your car (like ours) has replacement studs, you may be limited as to which wheels you can use with the adapters. Many replacement studs have a tapered end (like ours) about 1/8-inch long that's not threaded. This makes the stud stick out past the wheel adapter. If this is the case with your car, use a wheel that has hollow pockets cast into the back of the wheel between the stud holes, which will allow the extra stud length to sit inside the pockets on the wheels. You won't be able to use a wheel that's solid between the adapter's stud holes on the backside of the wheel. The solution would be to either use a different wheel, or if you're intent on using wheels without pockets, install shorter OEM-type studs.

5 Luckily, these wheels had the pockets to clear the longer studs for our Baer brakes. Other '94-'04, 17-inch Mustang wheels may or may not have these pockets, so keep this in mind if your car has longer studs with the ends that aren't threaded. The '01-'04 Bullitt wheels (like ours) have the pockets, so if they're your choice, you'll be all set regardless of the type of stud you have on your car.

6 There is another set of choices to consider when it comes to the rear wheels. The adapter kit includes a pair of 1/2-inch spacers for the rear wheels as well as 10 longer wheel studs for the rear axles. The kit instructions state the use of the "rear thin adapters is not totally required." We found that to be true: There were no clearance issues with the 17-inch wheel and 245/45ZR17 tire at the back of our car. However, while the wheel and tire did fit, it was spaced too far inside the wheel well and didn't look quite right. The instructions also say that these thinner (1/2-inch) adapters space out the rear wheels so they're correctly positioned to put the rear tires on the same track as the fronts. However, to do this, you'll need to remove the rear axles on your car since the rear studs won't likely be long enough to allow for the adapter to fit between the brake drum (or rotor in the case of our car) and wheel. While replacing the studs is certainly a good choice, for now we're going to keep the car's existing 16-inch wheels in place. This brings us to a third possible solution. As shown in the next photo, we installed a 1-inch front adapter on the rear rotor, which placed the rear wheels just-right inside the rear fenderwell, which is the arrangement we used in the photos of the car with the 17- and 18-inch wheels in place. The only downside is that it requires two adapter kits to have 1-inch spacers with all four wheels. This extra expense is alleviated by not having to install the longer studs.

7 The 1-inch adapter bolts directly onto the rear-wheel studs, just like up front. This is a good way to go if you want to avoid installing new studs in your car's rear axles. However, our car has replacement studs due to its Baer brakes, so other studs on a given car might be long enough. Assess each situation on a car-to-car basis, considering factors such as what studs are in place, which brakes you have (OE or aftermarket), what size wheels you want to run, and what track variations you want or don't want between the front and back of your car.