1961 Alvis Tire Fitment Guide

1961 Alvis fitment centers on the TD 21, which uses two tire sizes: 640-15 and 670-15. Both are bias-ply sizes built for 15-inch rims. The 640-15 appears with published rim-width ranges from 4.00 to 5.00 inches depending on the tire chosen, while the 670-15 spans published ranges from 4.50 to 6.00 inches depending on brand and version.

That means a 1961 Alvis owner should confirm more than just the rim diameter before choosing a tire. Wheel width, desired sidewall style, and the stance you want on the car all matter. If your TD 21 still has its original-style wheels, compare their actual width against the tire's approved range before committing to either size.

On a 1961 Alvis, 640-15 is a numeric bias-ply tire size. The 640 designation refers to the tire's nominal section-width class in the older numeric system, and the 15 identifies the wheel diameter in inches. It is not a modern metric code, so it should be read as a period bias-ply sizing convention rather than translated directly into a current passenger-car size.

For a TD 21 owner, that matters because a 640-15 carries the shape, sidewall proportions, and wheel-fit expectations of an early-1960s bias-ply tire. If your goal is preserving the traditional look of a British grand tourer, this size keeps you in the era-correct format. Whitewall width and wheel-width compatibility still vary between individual 640-15 tires, so compare those details before choosing.

On a 1961 Alvis, 670-15 is also a numeric bias-ply tire size. The 670 portion identifies a larger nominal section-width class than 640-15, and the 15 means the tire mounts on a 15-inch wheel. Like 640-15, it follows the older numeric bias-ply system rather than a modern radial or metric format.

That gives 1961 Alvis TD 21 owners a second period-correct size path on the same wheel diameter. Many buyers look at 670-15 when they want a fuller sidewall presence or need a tire built around a wider approved wheel range. Since some 670-15 options start at 4.50-inch wheel widths and others extend to 6.00 inches, measuring the wheel before ordering is a smart first step.

Both 640-15 and 670-15 are correct-format bias-ply choices for a 1961 Alvis TD 21, so the decision is not about switching between bias-ply and radial behavior. It is mainly about which size best matches your wheels, the stance you want, and the sidewall treatment you prefer. The 640-15 group includes wide and narrow whitewall options, while the 670-15 group includes blackwall and wide whitewall choices.

A buyer focused on a slightly narrower traditional look may lean toward 640-15, while someone wanting a fuller visual presence may prefer 670-15. Neither choice should be made by appearance alone, though. Check wheel width first, then compare load ratings, sidewall style, and the overall restoration direction of the car before settling on one size.

1961 Alvis tires are available with meaningful sidewall variety. In 640-15, choices include wide whitewall and narrow whitewall versions. In 670-15, choices include blackwall and wide whitewall versions. All of these remain within the bias-ply family, but they create noticeably different visual results on the same car.

For a British luxury touring car such as the TD 21, sidewall style plays a large role in how formal, sporting, or export-market-correct the car appears. Owners restoring for a specific market presentation often care as much about the width of the whitewall as the tire size itself. Period photos, marque literature, and club guidance can help narrow down which sidewall treatment best suits your particular Alvis.

1961 Alvis coverage includes BFGoodrich and Firestone in 640-15, and Firestone, US Royal, Coker Classic, and Universal Vintage Tire in 670-15. That gives TD 21 owners a mix of historically familiar American collector-tire names and reproduction-focused offerings in the two sizes used on the car. Brand choice is tied not only to name recognition, but also to which sidewall style and wheel-width range you need.

A smart way to compare brands for a 1961 Alvis is to look at the combination of size, sidewall appearance, and published wheel compatibility rather than treating every 15-inch bias-ply as interchangeable. Firestone appears in both sizes, which can make it a natural cross-size comparison point. BFGoodrich, US Royal, Coker Classic, and Universal each broaden the visual and fitment options depending on which TD 21 setup you are trying to match.

1961 Alvis TD 21 tires share a 15-inch rim diameter, but the approved wheel-width range changes by size and by tire. In 640-15, published ranges run from 4.00-4.50 inches on one version to 4.50-5.00 inches on others. In 670-15, published ranges include 4.50-5.00 inches and 5.00-6.00 inches depending on the tire selected.

That spread is important because choosing by size alone can still leave you with the wrong tire for your actual wheel. Before fitting a new set to a 1961 Alvis, measure the wheel width bead-to-bead or have a specialist confirm it. Once you know the wheel width, you can narrow the field to the versions of 640-15 or 670-15 built for that wheel.

A 1961 Alvis TD 21 can use both 640-15 and 670-15 on 15-inch wheels, so the wheel diameter itself is compatible with either size. The remaining question is wheel width, because the approved ranges are not identical across all versions. Some 640-15 tires are intended for narrower wheels, while some 670-15 tires are intended for wider ones.

That makes the original wheel a good starting point, but not the only thing to verify. If your TD 21 still has its factory-style wheels, confirm their actual width and compare that measurement to the tire you want. This is especially helpful when moving from one approved size to the other, since visual preference alone should not override wheel-width compatibility.

A 1961 Alvis should be stored in a cool, dry, dark space away from direct sunlight, electric motors, welders, battery chargers, and other ozone-producing equipment that can age sidewalls. Because the TD 21 uses bias-ply tires, long periods of static storage can also encourage flat-spotting more readily than many modern radials. Clean floors, stable temperatures, and proper inflation all help preserve the tires while the car is parked.

If the car sits for extended periods, move it slightly from time to time or place it on stands in a way that follows normal collector-car storage practice. Tire covers can help limit light exposure. Before the first drive of the season, inspect each tire closely for cracking, bulges, pressure loss, and signs that a long static period has changed how the tire rolls.

On a 1961 Alvis, tire life should be judged more by age and condition than by miles alone, because collector cars often accumulate limited road use. A sound rule is to begin evaluating tires carefully once they reach about five to seven years of age and to treat around ten years as the point where replacement deserves serious consideration regardless of remaining tread. The DOT date code on the tire helps establish age.

That matters on a TD 21 because a beautifully restored car may still be riding on old rubber that looks acceptable at a glance. Bias-ply tires can retain a presentable appearance while aging internally. If the car is new to you, checking age codes should be one of the first tire-related tasks, even before deciding whether the current size and sidewall style are what you ultimately want.

Tires on a 1961 Alvis should be inspected before every drive and again before any extended outing. Look for sidewall cracking, irregular wear, cuts, bulges, exposed cords, and pressure loss, and make sure the spare is still serviceable as well. Since collector cars often spend long periods parked, a quick visual check alone is not enough if the car has been sitting for months.

A more thorough seasonal inspection is worthwhile on a TD 21, especially before touring events. Check valve stems, confirm pressures when the tires are cold, and pay attention to how the car feels in the first few miles in case storage flat-spotting is present. Regular inspection is one of the easiest ways to catch age-related problems before they turn into road-trip issues.

A 1961 Alvis TD 21 belongs to an era when bias-ply construction was still the expected original-type format for many luxury and grand touring cars, and both 640-15 and 670-15 appear in the tire sizes associated with the model. That means an owner pursuing period-correct presentation should stay within the bias-ply family first, then confirm the exact size against the car's build, market, and long-standing marque references.

Because Alvis was a low-volume British manufacturer with detail variations that can matter to restorers, the most careful approach is to compare the car against factory literature, old photos, and Alvis club guidance before finalizing size and sidewall style. The key point is that 1961 TD 21 authenticity begins with the correct bias-ply format, not with substituting a modern sizing system.

Correct tire fitment absolutely matters when a 1961 Alvis is judged for authenticity. Size, construction type, and sidewall treatment all affect whether the car presents as properly restored for its period. A TD 21 wearing an incorrect visual treatment or a size that alters the car's stance can stand out quickly to judges and marque-savvy spectators, even if the difference seems minor to a casual observer.

For show use, think of the tires as part of the car's exterior design, not just a maintenance item. On a hand-finished British GT, the relationship between wheel opening, sidewall height, and whitewall width can influence the car's whole character. Event standards vary, so owners aiming for concours-level accuracy should confirm what a specific Alvis club or judging body expects before choosing between the available bias-ply options.

For a 1961 Alvis running 640-15 tires, BFGoodrich and Firestone differ mainly in sidewall presentation and approved wheel range. BFGoodrich appears as a 3.00-inch wide whitewall with a 4.00-4.50-inch rim-width range and a 1,190-pound load rating at 32 psi. Firestone appears in 2.75-inch and 2.125-inch wide whitewall versions with 4.50-5.00-inch rim-width ranges and the same 1,190-pound rating at 32 psi, plus a 1.00-inch narrow whitewall at 970 pounds at 32 psi.

That gives TD 21 owners a meaningful restoration choice rather than a simple brand swap. If your wheel is on the narrower side, the BFGoodrich version may align better with the wheel-width range. If your goal is a different whitewall proportion on a slightly wider wheel, one of the Firestone versions may better match the look you want without leaving the correct 640-15 bias-ply format.

1961 Alvis tires can be suitable for highway use when they are the correct size for the wheel, properly inflated, in sound condition, and driven within the limits of their construction and load capability. The available 640-15 and 670-15 tires here are bias-ply designs, and no explicit modern speed ratings appear on these products. On a car such as the TD 21, overall road safety also depends heavily on the condition of the brakes, steering, suspension, and alignment.

For practical driving, think of the tire as one part of a larger vintage-car system. A well-sorted Alvis on fresh, correctly fitted bias-ply tires can be very enjoyable on secondary roads and moderate highway stretches, but it should still be driven with the manners appropriate to an early-1960s grand tourer. If you are preparing for sustained higher-speed use, begin with a full chassis and tire inspection.

Published load figures for 1961 Alvis tire options include 640-15 examples rated at 1,190 pounds at 32 psi, with one narrow-whitewall 640-15 rated at 970 pounds at 32 psi, and 670-15 examples rated at 1,450 pounds at 32 psi and 1,550 pounds at 32 psi depending on the tire. Those figures show the pressure at which the tire reaches its stated load capacity, not necessarily the exact running pressure your TD 21 should use on the road.

For actual service pressure, start with the factory recommendation for the car when available, then compare it with the tire manufacturer's guidance for the specific tire you choose. Do not transfer a pressure figure from one size to another just because both fit a 15-inch wheel. Tire size, load capacity, and the car's weight distribution all affect what pressure makes sense.

Before a longer trip in a 1961 Alvis, inspect every tire for age cracking, cuts, bulges, irregular wear, and proper cold inflation pressure. Confirm that the spare is usable, that the valve stems are sound, and that each tire matches the wheel width it is mounted on. Since the TD 21 uses bias-ply tires in 640-15 or 670-15 form, it is also wise to watch for storage flat-spotting if the car has been parked for a while.

Tires are only one part of the pre-tour routine on an early-1960s Alvis. A longer drive also calls for checks of brakes, steering play, fluid levels, cooling, and lighting so the car's overall condition matches the confidence inspired by new or healthy tires. The goal is not just getting the size right, but making sure the whole touring package is ready for the road.