Plymouth P20 Tires

Plymouth P20 uses 670-15 for the 1950 model year. All listed products for Plymouth P20 are built around a 15-inch rim diameter, and most specify wheel widths centered on 4.50 to 5.00 inches, with some variations slightly outside that range depending on the tire series.

That means the fitment question on a Plymouth P20 is usually not about choosing between multiple sizes, but about confirming that the car still has its correct 15-inch wheels and selecting the right rim-width match. Once that is settled, the next decision is whether the car should wear blackwalls, narrow whitewalls, or wide whitewalls to suit its intended restoration style.

On a Plymouth P20, 670-15 is a numeric bias-ply size from the period tire system. The 670 represents the nominal section width in the older inch-based format, and the 15 identifies the wheel diameter in inches, which matches the 15-inch rims used by the listed Plymouth P20 products.

Modern buyers sometimes expect a more detailed metric code, but period numeric sizes are simpler and depend more heavily on wheel width and tire construction. On a Plymouth P20, that means you should read 670-15 as a period-correct bias-ply sizing standard and then verify that your wheel width matches the intended range of the specific tire you are considering.

Plymouth P20 listings here are entirely bias-ply, and the 670-15 offerings are treated as tube-type fitments. A tube is required with these Plymouth P20 tires, which is consistent with how collector-car bias-ply applications of this era are typically fitted.

That matters because tube selection needs to match the tire size and the wheel condition must also be suitable for tube use. On a Plymouth P20, it is wise to inspect the inside of the rim for rust, sharp edges, or old repairs before mounting new tires, since tube life can be shortened quickly by wheel problems that may not be visible from the outside.

Plymouth P20 tires in 670-15 are available in blackwall, narrow whitewall, and wide whitewall styles. The listings include blackwall choices for a more understated look, 1-inch narrow whitewalls, and several wide whitewall variations ranging from modest to very prominent period styling.

That gives a Plymouth P20 owner room to match the tire to the character of the car. A conservative driver-quality sedan may look right on blackwalls or a narrow whitewall, while a more formal or show-oriented restoration often benefits from a wider whitewall that better reflects late-1940s to 1950 visual taste.

Plymouth P20 tires in 670-15 are offered here by Firestone, US Royal, Coker Classic, Universal Vintage Tire, BFGoodrich, Excelsior, Avon, Goodyear, and STA. Those brands cover a broad mix of period-style collector tires, from straightforward blackwalls to several whitewall treatments and specialty series.

Brand choice on a Plymouth P20 usually comes down to the appearance you want, the series you prefer, and how closely you are trying to match a certain period-correct look. If authenticity matters, compare the sidewall width and tread character against period photos or marque references rather than choosing by brand name alone.

Plymouth P20 offerings in 670-15 include Firestone Classic Bias Ply, US Royal Classic Bias Ply, Coker Classic Bias Ply, Universal Classic Bias Ply, Silvertown Classic Bias Ply, Excelsior Bias Ply, Turbospeed Mk4, Super Cushion, Custom Super Cushion, Super Cushion Deluxe, and Super Transport. All are bias-ply, but they differ in brand identity, sidewall treatment, and intended character, with some aimed squarely at passenger-car presentation and one STA Super Transport listing leaning toward a truck-duty family.

For a Plymouth P20, that means the decision is less about basic fit and more about matching the tire to the car's mission. A stock-style restoration typically benefits from a classic passenger-car series with the right whitewall width, while a more utilitarian or specialty-use car may call for a simpler blackwall or heavier-duty visual profile.

Plymouth P20 should be stored on a clean, dry surface away from direct sunlight, electric motors, welders, battery chargers, and other ozone sources that accelerate rubber aging. Keep the tires inflated to an appropriate operating pressure for the tire and vehicle, and avoid leaving the full weight of the car in one exact spot for very long periods.

Long-term collector storage is easier on Plymouth P20 tires if the car is rolled occasionally or supported in a way that reduces prolonged flat-spotting. Clean tires with mild soap and water only, and avoid glossy dressings that can mask cracking or dry the rubber over time.

Tires on a Plymouth P20 should be inspected before each drive and given a more thorough check several times خلال the driving season. Look for pressure loss, cracking at the sidewall and tread, uneven wear, tube-related leakage, valve stem condition, and any signs that the tire has shifted or chafed on the rim.

Because Plymouth P20 uses bias-ply tube-type tires, small issues can become larger problems quickly if the car sits for long periods between outings. A hands-on inspection also helps catch wheel or suspension issues early, especially if the car begins to wander, vibrate, or pull in a way that feels different from its normal period driving character.

Tires on a Plymouth P20 should be replaced when age, cracking, hardening, impact damage, exposed cords, or persistent air loss show that the casing is no longer sound, even if the tread still looks usable. Collector cars often wear out their tires by time and environment rather than mileage, especially when they are driven only occasionally.

That principle is especially important on a Plymouth P20 because a bias-ply tire can look presentable long after its materials have begun to deteriorate. If the car has sat for years, or if a tire's age is uncertain, a specialist inspection is wiser than judging by appearance alone, since tube-type assemblies can hide internal issues not visible from the outside.

Plymouth P20 is listed here with a single 670-15 fitment for 1950, and the available replacements are all bias-ply tires in that size. The product range includes several period-style series from Firestone, US Royal, BFGoodrich, Goodyear, Coker Classic, Universal Vintage Tire, Excelsior, Avon, and STA rather than pointing to one single original factory tire brand.

For an exact restoration, the best approach is to treat 670-15 bias-ply sizing as the foundation and then compare sidewall style, tread appearance, and brand presentation against period literature or marque-club references. That will help narrow the choice to a tire that looks right for the specific Plymouth P20 you are restoring.

Correct tire fitment can affect both the presentation and the judged authenticity of a Plymouth P20. Size, construction type, sidewall treatment, and the overall visual stance of the car all influence whether the finished result looks convincingly period-correct to knowledgeable enthusiasts and judges.

On a Plymouth P20, the biggest authenticity decision is usually not size, since 670-15 is the listed fitment, but which version of that size best suits the car. Whitewall width and brand styling can change the car's appearance noticeably, so restorers aiming for show standards should compare their choice with period photos and marque-club guidance.

Plymouth P20 tires are available in blackwall, narrow whitewall, and wide whitewall styles, and any of those can shift the restoration's final character. Blackwalls suit a plainer, more restrained presentation, while narrow and wide whitewalls move the car toward increasingly dressy late-1940s and 1950-period styling.

The right answer for a Plymouth P20 depends on how the particular car was trimmed and how closely you are matching a period appearance. If originality matters, study factory literature, period photos, and marque examples from the same model year rather than choosing solely by personal taste, because whitewall width is one of the most visible styling cues on the whole car.

A properly mounted, correctly inflated new bias-ply tire in the right 670-15 size can be suitable for public-road use on a Plymouth P20 when the rest of the car is mechanically sound. Safe use depends on the full system working together, including wheels, tubes, brakes, steering, suspension, and alignment.

That means tire selection is only one part of roadworthiness for a Plymouth P20. Bias-ply tires drive differently from modern radials, with more sensitivity to road crown and a more period-correct feel, so a freshly restored car should be tested cautiously and sorted fully before longer road trips.

Before driving a Plymouth P20, check tire pressure, visible sidewall condition, tread condition, valve stems, lug security, and whether the tires are seated properly on the rims. It is also wise to inspect for flat spots from storage and confirm that the wheels themselves are free from cracks, bent flanges, or severe rust where the tube and tire seat.

A short pre-drive walkaround can prevent most tire-related surprises on a Plymouth P20. If the car has been stored for weeks or months, begin with a gentle, low-speed test drive and pay attention to vibration, pull, or heat buildup, since those symptoms often point to inflation, balance, wheel, or internal tire issues.

A Plymouth P20 on period-style 670-15 bias-ply tires should be driven at sensible speeds that respect both the tire design and the condition of the car. Even when the size is correct, a collector-car bias-ply tire is best treated as part of an older chassis system rather than as a substitute for modern high-speed touring rubber.

In practice, that means a Plymouth P20 should be driven within conservative limits that match its steering, brakes, suspension, and road conditions, not merely what traffic around it is doing. If the car is newly restored or recently returned to service, build speed gradually until you know how the tires, wheels, and chassis behave together.