1971 Triumph Spitfire Tires

The 1971 Triumph Spitfire uses two recognized tire sizes: 560-13 in bias-ply construction and 155R13 in radial construction. Both sizes are built around a 13-inch rim, so the basic wheel diameter stays the same even though the sizing system and tire construction differ.

That means the key choice is not simply diameter, but whether the car is set up for a numeric bias-ply tire or a Euro-metric radial. Before selecting either size, confirm the wheel width and the tire type already on the car, especially if the Spitfire has been changed from its earlier setup over the years.

The 1971 Triumph Spitfire uses a 13-inch rim diameter with both of its primary tire sizes. That applies whether the car is wearing a 560-13 bias-ply tire or a 155R13 radial, so rim diameter itself is not the point of difference between the two fitments.

Wheel width still matters, because the available tires are not aimed at exactly the same rim-width ranges. A radial and a bias-ply tire can share a 13-inch diameter while needing different wheel widths, so it is smart to measure the actual wheels on the car instead of relying only on the size stamped on the old tire.

560-13 is a vintage numeric bias-ply size. The 5.60 portion refers to the tire's nominal section width in inches, and the 13 identifies the wheel diameter in inches, making it a traditional small-car bias-ply fitment for a 13-inch wheel.

That older sizing style matters because it points to a bias-ply construction, not a modern metric radial. If a Spitfire currently has 560-13 tires, the owner should decide whether the goal is to keep that period-style construction or consider one of the radial equivalents while checking wheel width and overall clearance first.

560-13 is a bias-ply tire size on the 1971 Triumph Spitfire. It uses the older numeric sizing system common to vintage tires, and in this application it represents the traditional bias-ply fitment rather than a radial construction.

That distinction affects both appearance and setup. A Spitfire wearing 560-13 tires may have wheels and visual proportions chosen around a bias-ply tire, so anyone considering a change should compare wheel width, sidewall style, and available radial equivalents rather than assuming any 13-inch tire will behave the same way.

Radial equivalents for 560-13 include 155R13 as an 80-series metric radial, P155/75R13 as a 75-series P-metric radial, and P155/70R13 as a 70-series P-metric radial. Those three sizes give a 1971 Triumph Spitfire owner several ways to evaluate a radial alternative to the original numeric bias-ply format.

The practical difference is that they use different modern sizing conventions and profile families, not that they are automatically interchangeable. A 4 to 5 inch recommended rim-width range is part of that comparison, and the final check should always include the actual wheel width, tire dimensions, and available fender and steering clearance.

Start by confirming the current wheel diameter, wheel width, and the exact tire size already on the car. A 1971 Triumph Spitfire can move from 560-13 bias-ply to radial-equivalent sizes such as 155R13, P155/75R13, or P155/70R13, but that change should be evaluated as a fitment decision, not just a size label change.

The next step is checking the car in service position for steering, suspension, and fender clearance, especially if it has non-stock wheels or ride-height changes. It also helps to think through the goal of the conversion, since a radial changes the tire's presentation and may move the car away from a more traditional bias-ply look.

Begin with the correct primary size and construction for the way the car is set up. The 1971 Triumph Spitfire can use 560-13 bias-ply tires or 155R13 radial tires, so the decision starts with wheel compatibility and whether the car is being kept in a period-style configuration or driven on a radial setup.

After that, compare practical details within the right size, such as sidewall style, brand, tire series, rim-width range, and load specification where shown. A narrow or wide whitewall bias-ply gives a different visual result than a blackwall radial, so appearance goals should be weighed alongside wheel measurements and intended road use.

The available sidewall styles for the 1971 Triumph Spitfire include blackwall in the 155R13 radial size, plus narrow whitewall and wide whitewall in the 560-13 bias-ply size. That gives the car a clear split between a more understated radial look and a more traditional vintage sidewall presentation.

Choosing among them depends on how the Spitfire is being finished and used. A blackwall radial suits an owner leaning toward roadgoing radial fitment, while whitewall bias-ply options create a stronger period-style visual statement. The best comparison is made only after confirming the tire size and construction that belong with the wheels on the car.

The 1971 Triumph Spitfire has tire options from Michelin and Dunlop in the 155R13 radial size, and from BFGoodrich and Firestone in the 560-13 bias-ply size. Those brands cover both paths this car commonly takes: a metric radial setup or a traditional numeric bias-ply setup.

Brand choice should come after size and construction are settled, since the available brands are tied to different tire formats and visual styles. It also helps to compare the tire series attached to each brand, because the product grid may reflect different period-inspired character, rim-width suitability, and sidewall treatment within the proper size.

A period-style 1971 Triumph Spitfire usually starts with the 560-13 bias-ply size, since that preserves the older numeric format and traditional tire construction. Within that size, classic bias-ply choices are available from BFGoodrich and Firestone, which keeps the car closer to a vintage sports-car presentation than a modern blackwall radial.

Appearance still comes down to how the individual car is being restored or presented. If originality matters beyond general period style, it is worth checking marque references or historical vehicle documentation before settling on a particular brand or whitewall treatment, because period-looking and exactly as-delivered are not always the same thing.

Tire construction changes more than ride character on a restored 1971 Triumph Spitfire; it also changes how the car looks at a glance. A 560-13 bias-ply tire gives the car a more traditional vintage presentation, while a 155R13 radial brings in a later-style metric format and a simpler blackwall appearance.

That visual difference matters on a compact British roadster where wheel-and-tire proportion is easy to notice. Owners aiming for a restoration-oriented finish often start with the construction type first, then choose sidewall style and brand within that path so the tires support the overall character of the car rather than working against it.

Yes, modifications can affect tire fitment on a 1971 Triumph Spitfire even when the tire size sounds correct. Changes to wheel width, wheel offset, suspension height, steering components, or body clearance can alter how either a 560-13 bias-ply tire or a 155R13 radial sits and moves in the wheel opening.

A small sports car leaves less room for assumptions, so any altered setup deserves a careful clearance check at full steering lock and through suspension movement. Looking only at the 13-inch rim diameter is not enough, especially when the car may have been updated over time with aftermarket wheels or non-stock suspension parts.

Before driving a 1971 Triumph Spitfire on new tires, inspect the wheels for correct diameter and condition, confirm lug hardware, and verify that the tires have proper clearance to the fenders and steering components. It is also wise to check inflation pressure, valve stems, and the overall condition of the suspension and steering system.

A short, careful road test is the right follow-up after installation. Listen for rubbing, feel for pull or vibration, and recheck the tires once the car has settled from its first miles, because an older sports car may reveal wheel or chassis issues only after the new tires are actually carrying load on the road.

Tires on a collector 1971 Triumph Spitfire should be checked regularly for pressure, tread wear, sidewall cracking, cuts, bulges, and signs of air loss. Because cars like this often spend long periods parked, age and storage conditions can matter just as much as mileage in determining whether the tires remain roadworthy.

Good storage habits help preserve both bias-ply and radial tires. Keeping the car away from prolonged sunlight, excess heat, moisture, and ozone sources reduces deterioration, and occasional inspections prevent an older-looking tire from being mistaken for a healthy one. Any questionable tire condition deserves closer evaluation before the car goes back on the road.