1926 Cunningham Tire Fitment Guide

1926 Cunningham vehicles in this guide are centered on the Cunningham 8, and two sizes are associated with that model: 33X6.75 and 700-21. The 700-21 size mounts on a 21-inch rim, and the listed products in that size fit rim widths ranging from 3.00 to 4.00 inches depending on the specific tire. Both sizes are bias-ply rather than radial, which is consistent with the era and the type of vehicle Cunningham was building in the mid-1920s.

The practical takeaway is that year and make alone are not enough if your car has been restored, re-wheeled, or changed over time. Start by checking the size currently on the car, then verify the wheel diameter before choosing between 33X6.75 and 700-21. If your Cunningham 8 already has 21-inch wheels and you want the broadest product selection shown here, 700-21 is the clearest place to begin.

On a 1926 Cunningham, 33X6.75 is an antique diameter-by-section size. The 33 refers to the tire's overall diameter in inches, while 6.75 refers to the nominal section width. That differs from later numeric and metric systems because the first number is not the rim diameter. This style of sizing belongs to the brass and pre-war tire era, when large overall diameter and tall sidewalls were a normal part of luxury-car design.

That matters because a modern buyer might mistake 33 for a wheel size when it actually describes the tire's outside height. If your Cunningham 8 is fitted for 33X6.75, you should confirm the actual wheel dimensions and compare them to the tire currently on the car before making a selection. Owners restoring high-end pre-war automobiles often pay close attention to this style of sizing because it strongly influences stance and period appearance.

On a 1926 Cunningham, 700-21 is a numeric bias-ply size. The 7.00 indicates the nominal section width in inches, while the 21 indicates the rim diameter in inches. Unlike an antique diameter-by-section code, this format tells you the wheel diameter directly. It is still an early-era sizing system, but one that is easier for many owners to match to an existing wheel.

That makes 700-21 the more intuitive fitment to verify when your Cunningham 8 already has 21-inch wheels. It also helps explain why this size has the clearest product coverage here, including multiple sidewall styles. Once the wheel diameter is confirmed, you can narrow the choice further by appearance, rim-width compatibility, and whether the car is being restored for judged presentation or driven more regularly.

A 1926 Cunningham owner should choose between 33X6.75 and 700-21 by confirming which size the car is actually set up to use, not by treating them as interchangeable alternatives. Both are bias-ply constructions, so this is not a bias-ply-versus-radial decision. The meaningful distinction is fitment format and wheel setup: 33X6.75 is an antique diameter-by-section size, while 700-21 is a numeric bias-ply size built around a 21-inch rim.

If your Cunningham 8 already carries 21-inch wheels and you want the size with the clearest range of available products, 700-21 is the natural starting point. If the car is being restored around its earlier-style fitment and the present wheels and clearances support 33X6.75, that size may better suit the car's established configuration. Verify the wheel, the current tire markings, and the visual stance you want before settling on either one.

For 1926 Cunningham, the listed 700-21 products are available in Blackwall, Wide Whitewall, and Double-Whitewall styles. That gives Cunningham 8 owners a meaningful appearance choice even while staying within correct-era bias-ply construction. Whitewall treatments can dramatically change how a large pre-war luxury car presents, especially on a vehicle where tire sidewall height is such a visible part of the overall profile.

Blackwall is often the more restrained choice, while wide whitewall and double-whitewall versions create a more formal, display-oriented look. The right style depends on how your Cunningham is restored and how closely you are trying to match a specific period presentation. If you participate in judged events, check the standards used by your club or event before choosing a sidewall treatment, because construction and sidewall appearance can both affect authenticity.

The listed 700-21 tires for 1926 Cunningham come from Firestone and Michelin. Firestone appears in blackwall, wide whitewall, and double-whitewall Balloon forms, while Michelin appears in the Double Rivet series as a blackwall tire. Both names carry strong period associations, which is useful on a luxury American car from the 1920s where brand character can matter almost as much as size and sidewall style.

Brand choice on a Cunningham 8 often comes down to the look you want and the details of the product's fitment range. Firestone gives the broadest appearance spread here, while Michelin offers a traditional blackwall alternative in the same 700-21 size. Once size is settled, compare the specific tire's rim-width range, sidewall style, and load information rather than assuming every product in the size is the same.

For 1926 Cunningham, the listed 700-21 products fit a range of rim widths depending on the tire. Firestone Balloon versions fit 3.75 to 4.00-inch rims, while the Michelin Double Rivet in 700-21 fits 3.00 to 3.75-inch rims. All of those examples share the same 21-inch rim diameter, but they do not use the exact same rim-width range. That difference matters on a heavy pre-war luxury car where tire shape and seating need to match the wheel properly.

Check the wheel on your Cunningham 8 before selecting a specific product, especially if the car has mixed components from an older restoration. A tire that matches the diameter but falls outside the wheel's width range can affect how the sidewall sits and how the car presents visually. Matching both rim diameter and approved rim width is the right way to narrow the choice once you know you need 700-21.

A 1926 Cunningham can only use both listed tire sizes if the wheels and overall setup match the requirements of each size. The 700-21 tires shown here mount on 21-inch rims, which gives a clear reference point for that fitment. The 33X6.75 size is a different style of designation, so it should not be treated as automatically interchangeable with 700-21 simply because both belong to the same year and model family.

That means the original wheels can be used with both sizes only after you confirm the actual wheel dimensions and the way the car is presently configured. Many pre-war cars have lived through decades of restoration changes, and those changes can affect what size is appropriate now. If you are unsure, inspect the wheel itself and compare it with the tire currently fitted before assuming either size will work on the same wheel.

A 1926 Cunningham should be stored in a cool, dry, dark space away from direct sunlight, electric motors, welders, furnaces, and other ozone-producing equipment. Bias-ply tires are especially prone to flat-spotting and sidewall aging when a heavy collector car sits in one place for long periods. Keeping the tires clean, properly inflated, and off damp concrete helps reduce avoidable deterioration in both the tread and sidewall.

Move the car periodically if possible, or use stands correctly if it will be stored for an extended season. Owners of large pre-war cars often notice flat-spotting more readily because of the tire construction and vehicle weight, even when the tires are otherwise healthy. Good storage habits protect the tire investment and help the Cunningham feel smoother and more predictable when it returns to the road.

On a 1926 Cunningham, tire life is usually governed more by age than mileage. Collector vehicles often accumulate relatively few miles, so sidewall condition, internal aging, and storage history matter more than tread wear alone. A sensible rule is to begin evaluating vintage-use tires carefully once they are around five to seven years old and to consider replacement around the ten-year mark regardless of remaining tread. The DOT date code on the tire is the key reference point for age.

That timeline can shorten if the Cunningham has been stored poorly, exposed to sunlight, or allowed to sit under load with low inflation. A lightly driven pre-war car may still need replacement tires even when the tread looks presentable from a distance. Treat age as a primary service factor and use annual inspections to decide whether the tire is still appropriate for road use.

Tires on a 1926 Cunningham should be inspected before every drive and again before any longer outing. On a car of this age, you want to look for sidewall cracking, tread separation signs, impact damage, uneven wear, and any loss of pressure since the last use. Valve stems deserve close attention as well, especially on older collector cars where the tire may not be the only aging rubber component involved in holding air reliably.

A pre-drive inspection is especially important on a heavy luxury car because the tire carries substantial visual and functional responsibility. If the Cunningham has a spare, inspect that tire too rather than treating it as decorative insurance. Small issues that seem harmless in the garage can become much more serious once the car is on a tour, parade route, or sustained road drive.

A 1926 Cunningham 8 would originally have been fitted with bias-ply tires, because radial construction did not define American luxury-car fitment in that period. The sizes associated here with the Cunningham 8 are 33X6.75 and 700-21, both of which belong to the pre-war bias-ply world. That places the restoration focus on selecting the correct size family and the right sidewall presentation, rather than choosing between old and modern construction types.

For an exact restoration, confirm your car's present wheels and consult Cunningham or Full Classic marque specialists if you are trying to match a particular coachwork style, market delivery, or judging standard. Original-equipment branding should not be assumed unless you have car-specific evidence. On a car this rare and prestigious, authenticity usually comes from getting the size, construction type, and overall visual character right together.

Correct tire fitment absolutely matters when showing a 1926 Cunningham. Judges and knowledgeable enthusiasts will notice whether the car carries an era-appropriate bias-ply tire, whether the size suits the car's proportions, and whether the sidewall treatment matches the presentation you are aiming for. On an upper-tier pre-war automobile, tire stance and sidewall look are a visible part of the car's overall authenticity, not just a maintenance detail.

A radial substitute, an obviously modern sizing format, or a sidewall style that clashes with the car's restoration theme can stand out quickly even to casual observers. For event-specific standards, use the judging manual or club guidance tied to the show you attend. That is especially important with low-production prestige makes like Cunningham, where accepted restoration norms may be narrower than they are for more common classics.

For a 1926 Cunningham in 700-21, Firestone Balloon and Michelin Double Rivet differ in fitment range and sidewall presentation. Firestone Balloon versions fit 3.75 to 4.00-inch rims and are offered in blackwall, wide whitewall, and double-whitewall forms, with listed load figures of 1930 pounds at 40 psi on the Firestone examples shown here. Michelin Double Rivet is offered as a blackwall and fits a narrower 3.00 to 3.75-inch rim-width range.

That means the choice is not only about brand name but also about wheel compatibility and the visual style you want on the car. If your Cunningham 8 has wheels on the narrower end of the 700-21 range, the Michelin fitment may align differently than the Firestone. If sidewall appearance is a major part of the restoration plan, Firestone provides more visual options within the same overall size.

1926 Cunningham tires can be used for road driving when they are in good condition, correctly fitted, and appropriate for the car, but they remain bias-ply tires designed in the spirit of a pre-war automobile. No speed ratings are shown here for the listed 33X6.75 or 700-21 products, so the sensible approach is to operate within the limits of the tire's condition and the vehicle's own mechanical capabilities. On a car from 1926, brakes, steering, suspension, and overall road manners usually become the practical limiting factors before any idea of modern sustained-speed driving.

That does not make the tires unsuitable; it means the car should be driven as an early luxury automobile, not like a modern highway cruiser. Keep speeds appropriate, maintain proper inflation, and inspect the tires closely before extended travel. A healthy bias-ply setup on a well-sorted Cunningham 8 can provide enjoyable touring service, but prudence and preparation matter more than outright speed potential.

Inflation pressure for 1926 Cunningham tires should be chosen by size and by the specific tire's published rating, not copied broadly from one product to another. In the listed 700-21 range, Firestone examples show a maximum load of 1930 pounds at 40 psi. That figure is useful as the tire's rated reference point, but it is not automatically the operating pressure every Cunningham 8 should run in every condition.

Use the vehicle's original literature or trusted marque guidance for the car's intended operating pressure, then compare that with the reproduction tire's own rating and limits. Pressure influences ride, contact patch shape, and steering feel on a large bias-ply car, so small changes can make a noticeable difference. Keep left and right pressures matched, and avoid carrying a pressure figure from 700-21 over to 33X6.75 without confirming it specifically.

Before taking a 1926 Cunningham on a longer drive, inspect each tire for cracking, cuts, bulges, exposed cord, irregular wear, and pressure loss. Check the valve stems, make sure the spare is usable, and confirm that the tire sidewalls are free of damage from age or storage. On an automobile from the mid-1920s, the tire inspection should be part of a larger pre-drive review that also includes brakes, wheel hardware, steering response, fluid levels, and the basic readiness of the car.

Longer tours expose a pre-war car to heat, road crown, and sustained running that it may not see on short local drives. Catching a marginal tire in the garage is far better than discovering it after the Cunningham is fully loaded and underway. If anything about the sidewall, pressure retention, or ride feel seems questionable, resolve it before the trip rather than treating the drive as the test.