1949 Plymouth P18 Tires

The primary tire size for a 1949 Plymouth P18 is 670-15. That is a numeric bias-ply size used on a 15-inch rim, and it is the core fitment to start with when replacing tires on this vehicle.

Because the Plymouth uses one main size, the next step is choosing the right version of 670-15 rather than sorting through multiple primary fitments. Check the actual wheel diameter and width on the car, especially if it has had wheel changes over the years, then compare sidewall style, tire series, and whether you want to stay with bias-ply construction or explore a radial equivalent.

The 1949 Plymouth P18 uses a 15-inch rim with its primary 670-15 tire size. That 15-inch diameter is the wheel size tied to the original-style bias-ply fitment for this vehicle.

Rim diameter is only part of the fitment picture, so it is worth checking wheel width before ordering tires. Many 670-15 bias-ply options are intended for relatively narrow vintage wheels, while the radial-equivalent choices call for their own wheel-width review. A car that has been updated with later wheels should be measured rather than assumed to still match its original-style setup.

On a 1949 Plymouth P18, 670-15 is a numeric bias-ply size. The 670 refers to an approximate nominal section width of 6.70 inches, and the 15 indicates the wheel diameter in inches.

That older sizing format matters because it does not read like a modern metric radial size. Buyers comparing new tires for a Plymouth P18 should recognize that 670-15 is the original-style bias-ply fitment format, while sizes such as 195R15 or P205/75R15 are radial equivalents that need separate checks for wheel width, overall dimensions, and clearance before making a change.

For the 1949 Plymouth P18, 670-15 is a bias-ply tire size. That is the primary construction associated with the vehicle's original-style fitment, and the available 670-15 products for this application are bias-ply tires.

Staying with bias-ply keeps the sizing format and traditional presentation aligned with the car's late-1940s character. A change to radial construction is still possible through equivalent sizes, but that becomes a conversion decision rather than a primary fitment decision. Wheel width, tire dimensions, and body or steering clearance should all be reviewed before moving away from the original-style construction.

Radial equivalents for 670-15 include 195R15, P205/75R15, P215/70R15, and 670R15. Those choices cover an 80-series metric radial, a 75-series P-metric radial, a 70-series P-metric radial, and a bias-look radial format.

Each option approaches the original size from a slightly different sizing convention, so the choice is not only about construction. The recommended rim-width range given for these equivalents is 5 to 7 inches, which makes wheel width a key checkpoint. Tire dimensions and clearances should also be reviewed carefully so the alternative suits the Plymouth's actual wheel and suspension setup.

Start by confirming the Plymouth's actual wheel diameter and width, then compare the available radial-equivalent sizes for 670-15: 195R15, P205/75R15, P215/70R15, and 670R15. The recommended rim-width range for those equivalents is 5 to 7 inches, so the wheel itself is one of the first things to verify.

The rest of the check should focus on how the tire works with the car's real-world setup. Measure available clearance at the fenders and steering stops, inspect suspension condition, and make sure the tire's dimensions suit the way the car sits and drives. A Plymouth that still has narrow original-style wheels may call for a different decision than one that has already been updated.

The first priority is staying with the correct primary size, 670-15, and confirming that the tire matches the car's 15-inch wheel setup. From there, the real comparison is among bias-ply series, sidewall appearance, rim-width specifications, and product details such as load figures where they are given.

A restoration-minded Plymouth may point toward a traditional blackwall or whitewall bias-ply, while a car driven more regularly may lead the owner to also review radial equivalents. Wheel width deserves close attention because some 670-15 choices are intended for narrower rims than others. Matching the tire to the car's actual wheels and intended use matters more than picking by brand name alone.

Tires for the 1949 Plymouth P18 are available in blackwall, narrow whitewall, and wide whitewall styles within the 670-15 size. That gives the car owner a broad range of visual choices while staying in the primary vintage-size format.

Sidewall style has a major effect on how a late-1940s Plymouth presents, especially on a restoration or preserved driver. A blackwall keeps the look more understated, while narrow and wide whitewalls move the car toward different period-style appearances. The right choice depends on the look you want, along with the tire series and wheel specifications that match the car's current setup.

The 1949 Plymouth P18 has 670-15 tire options from Firestone, US Royal, Coker Classic, Universal Vintage Tire, BFGoodrich, Excelsior, Avon, Goodyear, and STA. Those choices span several vintage-style bias-ply series and multiple sidewall treatments.

Brand variety is most useful when it helps narrow appearance and specification differences rather than turning into a ranking exercise. Some options focus on classic bias-ply passenger-car presentation, while others bring different whitewall widths, blackwall styles, or specialized series character. Once the correct size is confirmed, compare wheel compatibility and the visual effect you want on the Plymouth before choosing among brands.

A period-style 1949 Plymouth P18 starts with the original-style 670-15 bias-ply format. That keeps the tire sizing and construction in line with the car's era, and it leaves room to choose among blackwall, narrow whitewall, and wide whitewall presentations depending on the look being pursued.

For many restorers, the question is less about modern performance and more about visual balance, stance, and the way the tire complements the car's trim and paint treatment. If exact historical originality matters, it is worth checking marque references and period photographs before selecting a whitewall width or brand presentation, since period-style and exact as-delivered appearance are not always the same thing.

Tire construction changes more than ride and handling on a restored 1949 Plymouth P18; it also affects the visual character of the car. A 670-15 bias-ply keeps the traditional vintage-size format, while a radial equivalent can alter the way the tire presents even when chosen as a careful alternative.

Owners who want a strongly restoration-oriented look often stay with bias-ply construction because it supports the car's period-style stance and overall impression. A bias-look radial such as 670R15 may appeal to someone who wants radial construction without moving as far from the original visual theme. Either way, sidewall style remains a separate appearance decision and should be chosen intentionally.

Yes, modifications can affect tire fitment on a 1949 Plymouth P18 even when the intended size remains 670-15 or one of its radial equivalents. Aftermarket wheels, suspension changes, ride-height changes, or brake conversions can all alter the space available around the tire.

That is why an older Plymouth should be measured as it sits today instead of being treated like an untouched factory car. Confirm wheel diameter and width first, then check clearance at the fenders, steering components, and suspension through the range of motion. A small fitment change at the wheel can matter just as much as the tire size itself on a modified collector car.

Before driving a 1949 Plymouth P18 on new tires, inspect the wheels for correct size and condition, make sure the tires are seated properly, and confirm that inflation matches the tire's requirements. It is also smart to look over suspension and steering components so the new tires are not being asked to compensate for worn hardware.

A careful walkaround after installation can prevent early problems. Turn the steering from lock to lock to check clearance, watch for any rubbing at the fenders, and recheck pressure after the first short drive. On a collector car that may have sat for long periods, a fresh tire install is a good time to examine valve stems, wheel hardware, and general chassis readiness.

Collector-car 670-15 tires on a 1949 Plymouth P18 should be maintained with regular pressure checks, routine visual inspections, and attention to age-related condition. Look for cracking, bulges, cuts, unusual wear, or slow air loss, especially if the car spends long periods parked between drives.

Storage conditions matter almost as much as mileage on a vintage Plymouth. Keeping the car away from prolonged sunlight, moisture, and ozone sources can help protect the tires over time. It also helps to move the car periodically and inspect tread and sidewalls before every meaningful drive, since low-use collector vehicles can age tires long before they wear them out.