1963 AC Cobra Tires

The 1963 AC Cobra uses two primary tire sizes: 640-15 and 670-15. Both are bias-ply sizes designed for 15-inch rims, and the Cobra Base is associated with both fitments rather than a single exclusive size.

That makes the first job confirming what is actually on the car now, especially if the wheels have been changed over time. Matching the tire to the wheel diameter is only part of the decision, because wheel width, overall stance, and available clearance also matter when choosing between the narrower 640-15 and the broader 670-15.

The primary tire fitments for the 1963 AC Cobra use a 15-inch rim diameter. Both 640-15 and 670-15 are built around that same 15-inch wheel size, so rim diameter stays consistent even though two tire sizes are associated with the car.

A 15-inch diameter does not settle the whole fitment question by itself. Wheel width still needs to be checked against the tire being considered, especially when comparing different brands and tire series or moving toward a radial equivalent. On a Cobra, confirming the actual wheel on the car is the best way to avoid ordering the right diameter in the wrong overall fitment.

The 1963 AC Cobra is associated with both 640-15 and 670-15, which means more than one primary bias-ply size can apply within this model coverage. Both sizes use the same 15-inch rim diameter, but they represent different section-width classes.

In practical terms, the buyer should not assume one size simply replaces the other without checking the car's actual wheel and tire setup. A Cobra that has been restored, modified, or fitted with different wheels over the years may favor one size over the other. Confirming the current wheel width and available clearance helps narrow the correct choice.

For the 1963 AC Cobra, 640-15 is a primary bias-ply tire size. It uses a vintage numeric sizing format and represents the traditional construction style associated with the car's listed original-type fitment direction.

That matters because staying with bias-ply construction preserves the period-style look and sizing convention, while moving to a radial changes the construction even if the alternative size is considered equivalent. Before converting, compare the wheel width to the radial's recommended range and make sure the tire's dimensions and clearances suit the Cobra's actual wheels and suspension setup.

Radial equivalents for 670-15 include 195R15 as an 80-series metric radial, P205/75R15 as a 75-series P-metric radial, P215/70R15 as a 70-series P-metric radial, and 670R15 as a bias-look radial. The recommended rim-width range attached to these equivalents is 5-7 inches.

Those options give a buyer several ways to approach a radial conversion, from a more conventional metric radial format to a bias-look radial that keeps a more traditional visual presentation. The choice should still be treated as an alternative, not an automatic swap, so wheel width, overall dimensions, and fender and steering clearance deserve a careful check before installation.

That decision depends on whether the priority is period-style presentation or a move to an equivalent radial format. The primary listed fitments for the 1963 AC Cobra are bias-ply in 640-15 and 670-15, while radial equivalents are available for both sizes in several metric and P-metric alternatives.

A restoration-oriented Cobra often stays with bias-ply construction for the correct vintage look and sizing style. A road-driven car may prompt consideration of a radial equivalent, but the switch should be approached carefully. Confirm the wheel dimensions, compare the equivalent's recommended rim-width range where given, and check clearance at full steering lock and suspension movement before making the change.

Start by confirming whether the car is using 640-15 or 670-15, since both are associated with the 1963 AC Cobra and both use 15-inch rims. After size confirmation, compare construction, sidewall style, brand, tire series, and any rim-width guidance tied to the specific product.

The right choice usually comes down to how the Cobra will be presented and driven. A blackwall can give a more understated competition-style look, while narrow or wide whitewalls create a different visual character. It also helps to compare product weight and load figures where they are stated, especially on a lightweight, performance-oriented car with a very visible tire stance.

Tires for the 1963 AC Cobra are available in blackwall, narrow whitewall, and wide whitewall styles. Those sidewall treatments appear across both 640-15 and 670-15 offerings, although the exact mix varies by size, brand, and tire series.

Sidewall style changes the car's visual character more than many buyers expect, especially on an open sports car with simple body lines and exposed wheel openings. Blackwalls usually lean toward a more purposeful look, while whitewall treatments create a more formal vintage presentation. Once the correct size is established, sidewall style becomes one of the clearest ways to match the tire to the Cobra's restoration theme.

Available tire brands for the 1963 AC Cobra include Firestone, BFGoodrich, Avon, Excelsior, US Royal, Universal Vintage Tire, Goodyear, Coker Classic, and STA. Brand coverage varies by size, with 670-15 offering the broadest range of choices across multiple bias-ply series and sidewall styles.

Brand selection should be part of a broader comparison rather than the only criterion. It helps to look at which series each brand offers in the needed size, whether the tire is blackwall or whitewall, and how the wheel-width guidance lines up with the Cobra's actual wheels. That approach keeps the decision focused on fitment and appearance instead of brand name alone.

A period-style 1963 AC Cobra usually starts with one of its primary bias-ply fitments, either 640-15 or 670-15, depending on the actual wheel and tire setup. Those sizes preserve the vintage numeric format and open the door to classic tire series from several historic and restoration-oriented brands.

From there, appearance choice becomes more specific. A blackwall generally keeps the look lean and sporting, while narrow or wide whitewalls push the car toward a different visual era and presentation. Buyers chasing exact historical authenticity should compare their chosen tire against marque references, period photos, and vehicle-specific documentation rather than assuming any correct-size vintage tire is automatically exact.

Tire construction changes more than ride and handling character on a restored 1963 AC Cobra; it also affects how the car sits and reads visually. The listed primary fitments are bias-ply, which keeps the car in a traditional vintage sizing and presentation language.

A radial equivalent can be a useful alternative for some owners, but it may create a different visual impression than a classic bias-ply tire, especially when the size format changes from numeric bias-ply to metric or P-metric. For a restoration-minded build, construction choice should be considered alongside sidewall style, wheel appearance, and the overall period theme of the car.

Yes, modifications can affect tire fitment on a 1963 AC Cobra even when the tire size itself is one of the correct listed options. Changes to wheel width, wheel offset, suspension height, steering components, or body clearance can all alter how a 640-15, 670-15, or radial equivalent sits on the car.

That is especially important on a compact sports car where space around the tire can be tight. A Cobra with aftermarket wheels or altered suspension should be checked at full steering lock and through suspension movement before finalizing a tire choice. Confirming the actual wheel dimensions on the car is often more useful than relying on assumptions from past ownership or restoration history.

Before driving a 1963 AC Cobra on new tires, inspect the wheels for correct diameter and condition, confirm that the tires are seated properly, and verify inflation pressure for the tire being used. It is also smart to check for any signs of rubbing at the fenders, suspension, or steering components.

A short, careful road test is the best next step. Pay attention to steering response, any vibration, and whether the tires maintain clearance during turns and over surface changes. On a lightly used collector car, it also helps to inspect the rest of the chassis before road use, since a fresh tire cannot compensate for worn suspension parts, loose steering, or neglected wheel hardware.

Collector-car tires on a 1963 AC Cobra should be maintained with regular pressure checks, periodic visual inspections, and attention to age-related condition. Whether the car uses 640-15 or 670-15, look for sidewall cracking, cuts, bulges, uneven wear, or slow air loss before each driving season and after longer storage periods.

Storage conditions matter as much as mileage on a low-use Cobra. Keeping the car away from prolonged sunlight, excess heat, moisture, and ozone sources helps preserve tire condition over time. Even tires with good tread deserve close inspection if the car is driven infrequently, since collector vehicles often age their tires out before they wear them out.