1963 Alvis Tire Fitment Guide

1963 Alvis vehicles in this range use two tire sizes: 640-15 and 670-15, both on the TD 21. Both are 15-inch bias-ply fitments rather than a mix of radial and bias-ply sizes across different models. The 640-15 products fit 15-inch rims with width ranges of 4.00 to 5.00 inches depending on the tire chosen, while 670-15 products fit 15-inch rims from 4.50 to 6.00 inches depending on brand and construction details.

That means the first step is not identifying a different model family, but confirming which of the two original-size paths your TD 21 actually uses. A car restored to factory appearance may call for one size, while a car with wheels changed long ago may be set up around another. Checking the existing tire size, measuring wheel width, and comparing both against your restoration goals will narrow the choice quickly.

On a 1963 Alvis tire, 640-15 is a numeric bias-ply size. The 6.40 portion refers to the nominal section width in inches, and the 15 refers to the wheel diameter in inches. Because it is a classic numeric format, it describes a bias-ply tire from the period rather than a later metric radial size with an aspect ratio and speed symbol built into the code.

For a TD 21 owner, that matters because the code tells you both the era and the style of tire the car was designed around. It also helps explain why whitewall width, sidewall appearance, and rim-width compatibility vary among products even when the base size stays the same. If your car currently wears a 640-15, the next comparison should be sidewall style and wheel-width suitability, not a modern metric conversion.

Within 1963 Alvis coverage here, the only model is the TD 21, and it uses two possible tire sizes rather than one universal fitment. Those sizes are 640-15 and 670-15, and both mount on 15-inch wheels. So the fitment question is not about different Alvis models needing different tires; it is about which original-style size belongs on your particular TD 21.

That distinction is useful because it keeps owners from assuming any 15-inch classic tire is automatically interchangeable. A 640-15 and a 670-15 share wheel diameter, but they are not the same overall section width or always the same wheel-width fit. If you are researching a newly acquired car, compare the current tire markings with the wheel width and the car's restoration history before settling on one size.

For a 1963 Alvis TD 21, the choice between 640-15 and 670-15 is primarily about matching the car's established fitment, since both are original-style bias-ply sizes for 15-inch wheels. The 640-15 generally fits narrower wheel widths, starting at 4.00 inches on some products, while 670-15 extends farther into wider wheel ranges and offers a broader mix of brands and sidewall treatments. Both keep the car in the correct period construction family.

A buyer choosing between them should start with the wheel already on the car and the look being preserved. If the car has a known factory-size reference, follow that first. If the car's history is less clear, wheel width is the best practical checkpoint because it quickly narrows which size family makes sense. Once size is confirmed, you can refine the decision by whitewall style, blackwall versus whitewall appearance, and brand preference.

1963 Alvis tires are available in several period-appropriate sidewall styles depending on size. In 640-15, the choices include wide whitewall and narrow whitewall. In 670-15, the range includes blackwall and wide whitewall. That gives a TD 21 owner room to match the car either to a more formal luxury presentation or to a plainer touring appearance without leaving the correct bias-ply era.

Sidewall style matters on a car like the TD 21 because it changes the visual balance of the whole vehicle, especially on a restrained British coachbuilt design. Whitewalls can emphasize elegance and mid-century presentation, while blackwalls often look more understated and sporting. If the car is being judged, confirm the expected sidewall treatment with marque references or event rules before making appearance the deciding factor.

1963 Alvis vehicles are covered by several classic tire brands across the two sizes used on the TD 21. The 640-15 is available from BFGoodrich and Firestone. The 670-15 is available from Firestone, US Royal, Coker Classic, and Universal Vintage Tire. All of these offerings stay within the bias-ply construction style appropriate to the car's period.

Brand choice on a collector car usually comes down to sidewall appearance, historical flavor, and the wheel-width and load details that suit your setup. Firestone spans both sizes, which can simplify a brand-consistent approach if you are comparing options. If visual authenticity matters most, compare each brand's available whitewall treatment first, then check whether the tire's wheel-width range and load rating align with your car.

Rim width depends on tire size and, in some cases, brand within the same size. For 1963 Alvis TD 21 fitments, 640-15 tires cover rim-width ranges from 4.00 to 5.00 inches depending on product. The 670-15 tires cover 4.50 to 6.00 inches depending on product. Both sizes use a 15-inch rim diameter, but wheel width still needs to match the tire you choose.

That is important because a tire can share the correct wheel diameter and still be wrong for the wheel's width. Before ordering, measure the actual wheel or confirm it from a trusted wheel reference for your car. Once you know that number, the choice between 640-15 and 670-15 becomes much easier, and you can avoid forcing a wider tire onto a wheel intended for a narrower section.

Original 1963 Alvis TD 21 wheels can potentially be used with both tire sizes in terms of diameter, because both 640-15 and 670-15 mount on 15-inch rims. That said, wheel width still matters. The 640-15 range begins as narrow as 4.00 inches on some products, while 670-15 commonly starts at 4.50 inches and may extend to 6.00 inches depending on brand.

In practice, that means the original wheel may accept either size only if its width falls inside the approved range for the specific tire being considered. Diameter alone is not enough. If your TD 21 still wears its original wheels, confirm their width before switching from one size family to the other. That simple step helps preserve handling balance, sidewall shape, and the overall look of the car.

A 1963 Alvis should be stored in a cool, dry, dark space away from direct sunlight, electric motors, battery chargers, welders, and other ozone sources that age rubber prematurely. Keep the tires at the correct inflation for storage, and if the car will sit for long periods, move it periodically or use stands appropriately so the same section of the bias-ply casing does not carry the load month after month.

That matters especially with bias-ply tires, which can take a temporary flat spot more readily during extended static storage than many later radial designs. Clean concrete is fine, but damp soil or prolonged contact with petroleum residue is not. A simple storage routine of proper inflation, occasional rolling, and a covered indoor environment will do more for long-term tire condition than most owners realize.

Tires on a 1963 Alvis should be judged more by age and condition than by mileage, because collector cars often travel relatively few miles each year. A good rule is to begin close evaluation around five to seven years of service and to treat around ten years from the date code as a point where replacement deserves serious consideration, even if tread depth still looks usable.

That approach is more realistic for a TD 21 than waiting for visible tread wear alone. Rubber ages internally as well as externally, and an elegant low-use touring car can still be running on tires that look decent at a glance but have hardened with time. Check the DOT or production date marking where applicable, inspect for cracking or stiffness, and replace on age if the car is driven regularly.

Tires on a 1963 Alvis should be inspected before every drive and again before any longer outing. Look for sidewall cracking, cuts, uneven wear, bulges, embedded debris, and any sign that the tire is losing pressure between drives. Because these are classic bias-ply applications, it is also wise to pay close attention to valve stem condition and the overall aging of the sidewall surface.

A short local drive can hide problems that become serious at sustained road speed, especially on an older grand touring car that may spend long stretches parked. Build tire inspection into the same habit as checking oil, coolant, and brake feel. If the car develops a pull, vibration, or steering change that was not there before, stop treating it as normal old-car character and inspect the tires immediately.

A 1963 Alvis TD 21 would have been fitted originally with bias-ply tires rather than modern radial construction, and the two size families associated with the car here are 640-15 and 670-15. That keeps the restoration conversation centered on classic numeric bias-ply sizing and 15-inch wheels. Original-equipment brand can vary by market, distributor, and period practice, so the safest historical anchor is size, construction type, and sidewall presentation rather than a single brand assumption.

For a restoration, that means bias-ply construction is the first authenticity box to check. After that, compare your car's history, old photos, and surviving paperwork if available. If the car is headed for concours judging, consult an Alvis owners' club or marque specialist to confirm whether your specific car should wear a blackwall, a narrow whitewall, or a wider whitewall treatment in addition to the base size.

Correct tire fitment absolutely matters when showing a 1963 Alvis, especially a car as design-conscious and low-volume as the TD 21. Judges and knowledgeable enthusiasts often notice whether the size, construction type, and sidewall style match the era and character of the car. A modern-looking substitute or a sidewall treatment that clashes with period expectations can stand out quickly, even if the car is otherwise restored beautifully.

For most events, the biggest authenticity markers are keeping the car on a correct-style bias-ply tire and choosing a sidewall appearance that suits the way the car would have been presented. The exact expectation can vary by show and club. If points judging is a serious goal, check the event standards early so the tire choice supports the restoration instead of becoming an avoidable deduction.

For the 1963 Alvis in 640-15, Firestone and BFGoodrich differ mainly in sidewall presentation, rim-width range, and available load rating. BFGoodrich offers a 3.00-inch wide whitewall with a 4.00 to 4.50 inch rim-width range and a 1,190-pound load rating at 32 psi. Firestone offers wider wheel compatibility at 4.50 to 5.00 inches, with 2.75-inch and 2.125-inch wide whitewalls at 1,190 pounds at 32 psi, plus a 1.00-inch narrow whitewall at 970 pounds at 32 psi.

That means the choice is not only about brand name, but also about how the tire will sit on the wheel and the visual effect on the car. If your TD 21 has a narrower wheel, the BFGoodrich fit range may be the cleaner match. If your wheel is wider or you want more whitewall-width choices within the same brand family, Firestone offers more appearance variation in 640-15.

1963 Alvis tires in these sizes are classic bias-ply products, and highway suitability begins with using the correct size on the correct wheel in sound condition. No speed ratings are marked in the available size descriptions here, so the more important real-world limit is often the overall condition of the tire and the mechanical state of the car. On a 1963 grand tourer, brakes, suspension condition, steering precision, and age-related maintenance can be just as important as the tire itself.

For normal road use, a healthy, properly inflated bias-ply tire can serve well, but it should be driven with the expectations appropriate to a 1960s car. Bias-ply tires respond differently from modern radials, especially in tracking, steering feel, and braking behavior. Before a sustained highway trip, make sure the car is stable at speed, the tires are age-sound, and the spare is in equally usable condition.

For 1963 Alvis tires, the tire's rated pressure and the car's factory-recommended operating pressure are not always the same thing. The 640-15 products here carry load figures at 32 psi, including 970 pounds at 32 psi on one narrow whitewall option and up to 1,190 pounds at 32 psi on others. The 670-15 products reach 1,450 pounds at 32 psi on some tires and up to 1,550 pounds at 32 psi on another.

Use those pressure figures as tire load references, not as an automatic inflation target for every TD 21. The right running pressure should be confirmed against the owner's manual or a trusted Alvis reference, then checked against the tire manufacturer's guidance for the specific reproduction tire you choose. Never transfer a pressure assumption from 640-15 to 670-15, because the load and casing characteristics are not identical.

Before a longer drive in a 1963 Alvis, inspect each tire for cracking, cuts, tread separation signs, bulges, and uneven wear, then verify cold inflation pressure and make sure all valve stems are in good condition. Confirm that the spare is inflated and serviceable, especially on a collector car that may still rely on period-correct equipment. Because the TD 21 uses bias-ply tires, pay attention to any vibration or pull that suggests a casing or balance issue.

Tires are only one part of the pre-trip checklist on a hand-built 1960s British grand tourer, but they are the easiest place to catch trouble before it strands the car. A longer drive is also the wrong moment to discover that an old spare, tired valve stem, or cracked sidewall has been aging quietly in the background. Give the tires a close walkaround before every substantial outing, not after the first problem appears.