There were many things that Mopar got right during the age of muscle cars, and one was capturing an aggressive, intimidating look and applying that look to their performance models. With eye-popping colors, in-your-face decals, and purposeful scoops and spoiler packages, Mopars of the day were often mistaken as being modified even in stock form. Chrysler did such a good job styling their cars that we often wonder why some owners attempt to better their car's styling with aftermarket components, even though we do appreciate nicely modified Mopar iron. So when we build our own project cars, we tend to favor cars that look stock to the casual observer, but perform better than the factory ever intended. So after considering the wheel and tire options for the '71 Road Runner we've been working on, we decided to order a set of 15-inch Mopar Rallye wheels with Firestone Wide-O-Oval tires from Coker tire.
With so many options available, choosing the wheels and tires for your Mopar can be a daunting task. In our central Florida, location we counted no less than six tire stores in a two-mile stretch of road, and the latest fad seems to be wheel and tire rental stores. And while we generally considered a nice set of lightweight aluminum racing wheels with sticky performance tires to be the right choice for this project, the idea of a factory looking '71 Road Runner that would outrun flashier looking cars (like a certain staff Valiant) in the quarter-mile held a certain appeal. Since the FAST drag cars are running some stout quarter-mile times on their reproduction bias-ply tires, we challenged ourselves to do the same.
Coker Tire and Specialty Wheel offer nearly every combination of brand-new, reproduction factory wheels and tires, including rims that are wider than the Chrysler Corporation's offerings of the time. A check of Coker Tire's website showed their wide variety of wheels and tires, and we quickly located the combination we wanted for our Plymouth. As an original 383/three-speed car, our Road Runner would have been equipped with 14-inch steel or Rallye wheels from the factory, and performance bias-ply tires. Since our goal was to duplicate the factory look, we chose a set of 15-inch Rallye Wheels for our car, along with Firestone Wide-O-Oval bias-ply tires. Although the Mopar Rallye wheels were introduced on B-Bodies a year prior to 1971, they arguably are one of the best looking wheels for a '71 and up B-body. Because we were only interested in the appearance of a factory look and not actual factory equipment, we chose to stagger the wheel and tires sizes from front to rear.
Up front, we chose 15-inch diameter Rallye wheels with a 7-inch rim width, combined with F70-15 inch bias-ply tires. The F70s have an overall diameter of 26.9 inches, a section width (bulge to bulge) of 8.3 inches and 6.5 inches of tread. In the rear we chose the same 15-inch diameter wheels, but with a wider 8-inch rim width, and chose slightly larger G70-15 tires. As some of the largest available factory tires of their time, our rear selections offer a 27.9-inch diameter, 8.5-inch section width, and 6.7 inches of tread. Comparatively, these tires are nowhere close to modern performance car tires, but consider that we're talking about 40-year-old technology, and also remember that though bias-ply tires aren't known for their superior handling, there was a big reason that most muscle cars were equipped with bias-ply tires from the factory.
Steel belted radial tires have been around since long before muscle cars gained popularity, but didn't see much use on performance vehicles (or any automotive applications) of the era because of safety reasons. Even though cars of the time would certainly have benefited from the strength and sidewall rigidity of a steel-belted radial, radials of the time were not able to withstand the heat of sustained high speed, and as this author can attest could blow apart doing body damage or at worst, causing loss of vehicle control at high speed. The causes of this problem have been debated, but in general terms the outer rubber plies of the tire would expand at a higher rate than the inner steel radial plies when heated by high-speed driving, eventually causing the outer rubber tread to separate from the tire. Modern radial tires are better engineered and speed-rated, ensuring they don't come apart, but back in the day radial tires were the cause of more than one wild ride or, unfortunately, often a totaled car.
Due in part to their construction from polyester, fiberglass, and rubber plies rather than steel and rubber plies, and also because of their bias design, bias-ply tires of the late '60s and early to mid '70s were a safer alternative for cars capable of 150 mph or higher top speeds. So for their time, tires like our Firestones were just about the best you can get, but compared to modern high-performance tires, they obviously come up a little short. For the purpose of looking stock, however, these wheels and tires really hit the mark. The wheels are powdercoated in the original argent silver color for a more durable finish than painted originals. Each wheel is also inspected for machining accuracy, concentricity, and run-out before being shipped.
We ordered our wheels and tires as a combo package, so the tires came mounted on the wheels, balanced, and filled with nitrogen. We also ordered all new trim rings and lug nuts for our wheels as well, and decided to deviate from a dead-on factory look in one area, the center caps. Seeing that Specialty Wheel offers a charcoal version of the correct cone-style center cap for our car, we decided the darker color would highlight the black stripes and spoilers on our car and ordered a set of four. The right wheels and tires will complement any car, and it's hard to beat the look of factory Mopar Rallye wheels.
On a technical level there's really nothing difficult about changing wheels and tires, meaning this is an improvement that any enthusiast can easily accomplish in an hour or so. We love the way our car looks and drives with the new wheels and tires, and also appreciated the ease of installation compared to the visual gratification of this project. Our B-body drives nicely and seems to handle well, though we won't drive too aggressively until we get to the track. If you're looking for a way to dramatically enhance the appearance of your vehicle, you should definitely consider new wheels and tires.
