1958 Morgan 4-4 Series & Plus 4 Tires

The 1958 Morgan 4-4 Series & Plus 4 uses two primary tire sizes: 560-15 in bias-ply construction and 155R15 in radial construction. Both sizes are tied to a 15-inch rim, so the vehicle can be approached either as a traditional bias-ply application or as a radial-equipped classic sports car.

The important next step is deciding which construction matches the car's current wheel setup and your intended use. A restoration-oriented owner may stay with 560-15 bias-ply, while a road-use-focused owner may look at 155R15 radial choices. Wheel width, tire clearance, and the car's present stance should all be checked before settling on either direction.

Both tire sizes used on the 1958 Morgan 4-4 Series & Plus 4 are built around a 15-inch rim diameter. That applies to the 560-15 bias-ply size and the 155R15 radial size, so wheel diameter stays consistent even though the tire construction and sizing format change.

Rim diameter is only part of the fitment picture on a narrow-bodied British sports car. The wheel's actual width still matters, especially when comparing bias-ply and radial options, because different products within these sizes call for slightly different rim-width ranges. It is also worth confirming that the car has not been changed to aftermarket wheels over the years.

560-15 is a vintage numeric bias-ply tire size. The 560 portion represents an approximate 5.60-inch nominal section width, while 15 refers to the rim diameter in inches. On the 1958 Morgan 4-4 Series & Plus 4, it is the traditional bias-ply fitment rather than a modern metric radial size.

That matters because a 560-15 tire brings a different appearance and construction style than a 155R15 radial, even though both fit a 15-inch wheel. Buyers looking at this size should pay attention to sidewall presentation, wheel-width suitability, and whether the car is being kept closer to a period-style setup or prepared for more regular road driving.

560-15 is the bias-ply tire size used on the 1958 Morgan 4-4 Series & Plus 4. It is the traditional numeric format associated with vintage fitment, while 155R15 represents the radial option in this application. The two sizes share the same 15-inch rim diameter but differ in construction and sizing convention.

That distinction affects both appearance and setup. Bias-ply tires are often chosen when a more traditional look is important, while radial choices may be considered for different road-use preferences. Before changing from one construction to the other, it is smart to confirm the wheel width, inspect clearance at full steering lock, and make sure the rest of the car is in sound condition.

Radial equivalents for 560-15 include 155R15 and 560R15. The 155R15 option is the 80-series metric radial equivalent, while 560R15 is the bias-look radial equivalent. These alternatives keep the same 15-inch rim diameter but move away from the original numeric bias-ply construction.

Each equivalent should be treated as an alternative rather than an automatic substitute. A recommended rim-width range of 4 to 5 inches applies to the radial equivalents for 560-15, and that should be checked against the actual wheel on the car. Clearance around fenders, steering components, and suspension should also be verified before conversion.

A bias-look radial can be considered for this Morgan when the starting point is the 560-15 bias-ply fitment. In this application, the bias-look radial equivalent is 560R15. It is meant to offer radial construction while preserving a more traditional visual impression than a fully modern-looking metric radial.

That makes it a useful option for owners who want to stay closer to the car's vintage presentation without remaining strictly bias-ply. Even so, it still needs the same careful checks as any construction change. Wheel width, overall tire fit within the body, and steering clearance on a narrow sports car should be confirmed before making the switch.

Start with the role the car is meant to play. A 560-15 tire on a 1958 Morgan 4-4 Series & Plus 4 is a bias-ply fitment, so the main choices are construction style within that format, sidewall appearance, brand, and wheel-width compatibility. Available examples include blackwall, narrow whitewall, and wide whitewall presentations.

The best comparison points are not just visual. Check the wheel width on the car, think about whether the car is being restored or regularly driven, and compare the series that are actually offered in 560-15. A narrow open-wheel-style sports car can be especially sensitive to changes in tire shape, so keeping the size and wheel relationship in balance is important.

Sidewall choices for the 1958 Morgan 4-4 Series & Plus 4 depend on the tire size. The 155R15 radial options are offered as blackwalls, while the 560-15 bias-ply range includes blackwall, narrow whitewall, and wide whitewall versions. That creates a noticeable visual difference even before construction is considered.

A blackwall usually suits a restrained sporting presentation, while whitewall treatments can push the car toward a more stylized restoration look. Since this is a small British sports car, sidewall treatment has a strong effect on overall character. The practical move is to choose the correct size first, then select the sidewall style that best matches the way the car is being finished.

Tires for the 1958 Morgan 4-4 Series & Plus 4 are available from Firestone, Michelin, Avon, Vredestein, US Royal, Coker Classic, and Pro-Trac, depending on the size. The 155R15 radial assortment includes Firestone, Michelin, Avon, and Vredestein, while 560-15 bias-ply options include Firestone, US Royal, Coker Classic, and Pro-Trac.

Brand choice should be weighed alongside tire series, sidewall treatment, construction, and wheel compatibility rather than treated as the only decision. Some buyers will be focused on a traditional bias-ply look, while others will be comparing blackwall radial products in the 155R15 size. Matching the brand offering to the car's intended appearance and use usually leads to a clearer selection.

For a period-style presentation, the 560-15 bias-ply size is the natural starting point on a 1958 Morgan 4-4 Series & Plus 4. It keeps the vintage numeric sizing format and the traditional construction associated with many collector-era fitments. Blackwall, narrow whitewall, and wide whitewall versions are all available within that size.

The right choice depends on how strictly the car is being restored and what visual character is appropriate for the finished build. When exact originality matters, marque-specific references and historical documentation are worth consulting before settling on a sidewall treatment. For many owners, staying in the correct size and construction family is the most important first step.

Tire construction changes the look of a restored 1958 Morgan 4-4 Series & Plus 4 more than many owners expect. A 560-15 bias-ply keeps a more traditional visual character, while a 155R15 radial introduces a later-style metric size format and a different overall presentation, even though both use a 15-inch wheel.

That visual difference matters on a Morgan because the tire is such a visible part of the car's narrow, upright sports-car profile. Owners balancing authenticity and road use sometimes look at a bias-look radial to keep a more vintage appearance while moving to radial construction. The choice should reflect the car's restoration goal rather than appearance alone.

Modifications can absolutely affect tire fitment on a 1958 Morgan 4-4 Series & Plus 4. Even when staying with 560-15 or 155R15, changes to wheel width, wheel offset, suspension height, steering components, or body clearance can alter how the tire sits and moves through its travel on a compact sports car.

A Morgan that has been updated over the years should be measured rather than assumed to match stock dimensions. Checking clearance at full steering lock and through suspension movement is especially important, since a narrow body and exposed fender lines leave less room for error. Confirming the actual wheel on the car is often the most useful first step.

Before driving a 1958 Morgan 4-4 Series & Plus 4 on new tires, inspect the wheels for correct diameter and condition, confirm the tires are seated properly, and check inflation pressure carefully. It is also wise to look over the suspension, steering, and brake components, since an old sports car can reveal other issues once fresh tires are installed.

Roadworthiness depends on more than tread alone. Look for sidewall rubbing, verify that the tires clear the body and steering at full lock, and make sure the car tracks properly on an initial short drive. Any vibration, pull, or unusual contact should be addressed early before the Morgan is used for longer trips or spirited back-road driving.

Collector-car tires on a 1958 Morgan 4-4 Series & Plus 4 should be maintained with regular pressure checks, routine visual inspection, and careful storage habits. Whether the car wears 560-15 bias-ply tires or 155R15 radials, low annual mileage does not prevent age-related issues such as cracking, flat spotting, or gradual air loss.

A good routine includes checking tread and sidewalls before each drive, keeping the car away from prolonged sunlight and ozone sources during storage, and moving it periodically if it sits for long periods. It also helps to inspect the wheels and valve stems at the same time. Collector use is gentler than daily driving, but tire condition still needs close attention.