Miles Cook
June 1, 2002

It's nothing new to upgrade to a more substantial wheel and tire combination on any car-especially a daily-driven vintage Mustang. Even so, we wanted to clearly illustrate the dramatic difference a more beefy wheel-and-tire combo makes on a car such as this '65 fastback.

As far as looks go, take a look at the photos and see for yourself. We'll admit a restored show car has a certain cool look to it with bias-ply redline tires and small 14-inch styled-steel wheels or wheel covers. But we feel that when a car, such as our '65, doesn't fall under the watchful eye of a show judge, it looks 10 times better with the larger wheels and tires. Leave the skinny tires for the show.

When we bought this car it had the 14x5-inch styled-steel wheels you see here and whitewall tires. Frankly, it was just a Band-Aid to fit only slightly larger BFGoodrich (great tires, yes, but just not big enough for our tastes) 185/60R4 radial T/As on the pizza-cutter-sized wheels.

For the past several years a number of companies have offered larger 15x7-inch steel wheels in a number of styles for '64 1/2-'66 Mustangs. A few years back we had a '66 fastback with 15x7-inch styled-steel wheels that rode on 225/50HR15 BFGoodrich Euro T/A skins. The car looked awesome, and when we sold it, we missed its hunkered-down road-racer look.

We wanted to bring back the look, but with a 15x7-inch Magnum 500 wheel such as was used on '66 Hertz Shelbys and '69-'70 Boss 302s. Made by Specialty Wheels, Magnum 500 wheels are available from California Mustang, and like the styled-steel wheels on the '66 they are a perfect fit on this '65. As with the '66, we went with the same size tire, but a much more sticky BFG Comp T/A ZR in a 225/50ZR15.

There's more. Not only does the car look better, it performs dramatically better, too, as demonstrated by the handling and braking tests we performed (see sidebar). In a 600-foot slalom, we picked a whopping six-plus mph in slalom speed! And this from a Mustang with stock suspension. All the details are explained below.

Testing, Testing
We wanted to do more than just bolt on a new set of wheels and tires and say, "Gee, don't they look great?" We wanted to really put the rubber to the road and see how much better the car drives and handles both in the real world and at the track. Our big sister magazine Motor Trend tests hundreds of new cars and trucks every year. Among MT's usual battery of performance testing is a test that gives a clear picture as to how a car handles.

With six cones set 100 feet apart from each other, the test driver runs the car through this 600-foot "slalom" as quickly as possible without spinning. The faster a car runs through, the better its handling characteristics are. We took our '65 fastback to Motor Trend's test facility to measure braking distances from 60-0 mph and slalom speeds with both sets of wheels and tires-changing the wheels and tires at the track.

While the difference in braking was somewhat better (we were fighting to keep the rear brakes from locking up), the slalom speed improvement was amazing! The car traveled nearly seven mph faster than with the smaller tire-and-wheel baseline of 53.4 mph. Not only that, the car feels much better. To give you an idea of how dramatic 7 mph is in a slalom test, it's like reducing a quarter-mile e.t. on a dragstrip by about three seconds.

It's been said that adding a good set of tires is the single biggest thing you can do improve a car's handling. The numbers below speak for themselves.

  Braking Speed through
  60-0 mph/feet 600-foot slalom
14-inch wheels and tires: 147.1 53.4 mph
15-inch wheels and tires: 143.1 60.3 mph