1950 Plymouth P20 Tires

The primary tire size for a 1950 Plymouth P20 is 670-15. This is a numeric bias-ply size used on a 15-inch rim, and the covered 6 Cyl. sub-model uses that same fitment. For most owners, the size question is straightforward because there is one main factory-era sizing convention to follow on this vehicle.

Once the size is confirmed, the real choice becomes which 670-15 tire best matches the car and its use. Sidewall treatment, brand, tire series, and wheel-width compatibility can all influence the final selection. If the car has been modified with different wheels or suspension changes, those details should be checked before assuming the original size format is still the best match.

The 1950 Plymouth P20 uses a 15-inch rim with its 670-15 tire size. That rim diameter is the critical match point, since the tire is built around a 15-inch wheel. On an older Plymouth like this, confirming the wheel itself is just as important as confirming the tire size stamped on the sidewall.

Wheel width also matters when comparing actual tire options, because available 670-15 products are built around different rim-width recommendations. A car that still has its original-type wheels may be straightforward, but any later wheel swap should be measured before ordering tires. Checking both diameter and width helps avoid clearance issues and prevents choosing a tire that does not suit the wheel properly.

In the 670-15 size, the 6.70 refers to the tire’s nominal section width in inches, using the older numeric bias-ply sizing system, and the 15 refers to the wheel diameter. It is a period-style tire designation commonly seen on American passenger cars of this era, including the 1950 Plymouth P20.

That older numeric format differs from modern metric radial sizing, so it helps to interpret it correctly before comparing replacements. A 670-15 is not just a number on the sidewall; it also signals the original-style construction and proportions expected for the car. Owners considering a radial alternative should compare the equivalent size carefully rather than treating the older code as automatically interchangeable with any modern 15-inch tire.

For the 1950 Plymouth P20, 670-15 is the primary bias-ply tire size. That means the original-style fitment follows the construction and sizing convention common to early postwar American cars. The available 670-15 products for this vehicle are bias-ply offerings, with different brands and sidewall appearances available within that same traditional size.

Keeping a bias-ply tire preserves the original-style size format and a more period-oriented presentation. It also means the car should be evaluated around the wheel dimensions and driving expectations that suit a bias-ply setup. Anyone looking for a different construction should compare the available radial equivalents carefully and confirm wheel width, tire dimensions, and clearance before making a change.

Radial equivalents for 670-15 include 195R15, P205/75R15, P215/70R15, and 670R15. The 195R15 is a Euro-metric 80-series style radial, P205/75R15 is a 75-series P-metric radial, P215/70R15 is a lower-profile 70-series P-metric radial, and 670R15 is a bias-look radial intended to retain a more traditional visual character.

Those options give a Plymouth owner several ways to move from an original-style numeric bias-ply format into radial sizing, but they should be treated as alternatives rather than automatic replacements. A recommended rim-width range of 5-7 inches is associated with these equivalents. Wheel width, overall dimensions, and steering or fender clearance should all be reviewed before choosing one for actual road use.

A 670R15 bias-look radial is one of the radial-equivalent options associated with the 1950 Plymouth P20’s original 670-15 size. That makes it a useful consideration for owners who want a radial construction while keeping a more vintage tire appearance than a later metric-size sidewall may provide.

Even with the familiar-looking presentation, a bias-look radial is still a radial, not a bias-ply tire. The wheel setup should be checked the same way any construction change would be checked, especially for rim width and vehicle clearance. It can be a strong visual compromise for a restoration-oriented driver, but the choice should still be guided by the actual wheel and chassis configuration on the car.

Start with the correct 670-15 size and the 15-inch wheel it requires, then compare the available bias-ply choices by sidewall style, brand, tire series, and wheel-width suitability. On a 1950 Plymouth P20, those differences matter more than size selection because the primary fitment itself is straightforward.

A blackwall can give the car a plainer utility look, while narrow or wide whitewalls can shift it toward a more dressed, period-style presentation. Product specifications also vary in rim-width guidance, weight, and load figures, so it helps to compare the tire to the actual wheel on the car. If the Plymouth has later wheels or a different intended road use, that should shape the choice as well.

The 1950 Plymouth P20’s 670-15 tire size is available in blackwall, narrow whitewall, and wide whitewall styles. Those sidewall treatments appear across several bias-ply brands and series, giving the owner a meaningful appearance choice even while staying within the same basic size and period-style construction.

Sidewall style changes the visual character of the car more than many buyers expect, especially on a large-fender postwar sedan. Wide whitewalls create a dressier traditional look, narrow whitewalls are more restrained, and blackwalls keep things simple and understated. The best choice depends on how the Plymouth is being restored or presented, rather than on any assumption that one sidewall style suits every P20 equally.

Available 670-15 tires for the 1950 Plymouth P20 come from Firestone, US Royal, Coker Classic, Universal Vintage Tire, BFGoodrich, Excelsior, Avon, Goodyear, and STA. These brands cover several classic bias-ply series, with blackwall, narrow whitewall, and wide whitewall options represented within the fitment.

Brand choice is best approached as part of a broader comparison rather than a ranking exercise. One owner may focus on a certain tread presentation or sidewall treatment, while another may care more about matching a specific period-style look. It also helps to compare the stated rim-width range, tire weight, and load figure where available so the selected tire suits both the wheel and the intended use of the Plymouth.

A 670-15 bias-ply tire is the natural starting point for a period-style 1950 Plymouth P20 because it keeps the original-era sizing format and construction type associated with the car. Within that size, the main visual decisions are brand, tread series, and whether the car looks best with blackwall, narrow whitewall, or wide whitewall sidewalls.

The right choice depends on the character you want the Plymouth to project. A driver-grade restoration may lean toward a practical blackwall, while a more formal postwar look often points buyers toward a whitewall treatment. If exact originality matters at a high level, marque references, period photos, and vehicle-specific restoration documentation are worth checking before settling on a final appearance.

Tire construction changes both the stance and the visual language of a restored 1950 Plymouth P20. A 670-15 bias-ply keeps the older size format and the kind of sidewall presentation most buyers expect to see on a 1950 Plymouth, while a radial alternative can shift the look toward a more modern replacement style.

That difference becomes especially noticeable when the car is viewed from the side, where whitewall width, sidewall shape, and overall tire character frame the body lines. A bias-look radial can narrow the visual gap for owners who want radial construction without giving up a vintage impression. The best answer depends on whether the restoration priority is authentic period flavor, regular road use, or a careful balance of both.

Yes, modifications can affect tire fitment on a 1950 Plymouth P20 even when the original tire size is known. Aftermarket wheels, suspension changes, altered ride height, brake conversions, or body work can all change the space available for a 670-15 tire or for one of its radial equivalents on a 15-inch wheel.

A Plymouth that no longer has its original-style wheel setup should be measured rather than treated like a stock car. Wheel width and diameter need to be confirmed first, then steering clearance and fender clearance should be checked through the full range of motion. That becomes even more important when moving from the original bias-ply fitment to a radial equivalent with a different sizing convention.

Before driving a 1950 Plymouth P20 on new tires, inspect the wheels for correct diameter and condition, verify that lug hardware is appropriate, and confirm that the tires have proper clearance at the fenders, suspension, and steering components. It is also wise to check tire pressure and look over the rest of the chassis if the car has been sitting.

A collector-era car can have issues that are unrelated to the new tires themselves, including worn steering parts, weak shocks, sagging springs, or old wheel components. Those problems can affect how the car tracks and how the tires wear once it is back on the road. A careful once-over before the first drive helps the new tire choice perform as intended.

670-15 tires on a collector 1950 Plymouth P20 should be maintained with regular pressure checks, visual inspections, and attention to age-related condition. Even a car that is driven only occasionally can develop sidewall cracking, tread hardening, flat spotting, or air-loss issues if it sits for long periods without inspection.

Storage conditions matter as much as mileage on an older collector car. Keeping the Plymouth away from prolonged sunlight, excess heat, moisture, and ozone sources can help preserve the tires between drives. It also helps to inspect the tires before each outing and after longer storage, paying attention to cuts, bulges, uneven wear, and any change in how the car feels on the road.